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Sample records for plasma polymerized diethylene

  1. Wettability, optical properties and molecular structure of plasma polymerized diethylene glycol dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, T C A M; Algatti, M A; Mota, R P; Honda, R Y; Kayama, M E; Kostov, K G; Fernandes, R S [FEG-DFQ-UNESP, Av. Ariberto Pereira da Cunha 333, 12516-410 - Guaratingueta, SP (Brazil); Cruz, N C; Rangel, E C, E-mail: algatti@feg.unesp.b [UNESP, Avenida Tres de Marco, 511, 18087-180 Sorocaba, SP (Brazil)

    2009-05-01

    Modern industry has frequently employed ethylene glycol ethers as monomers in plasma polymerization process to produce different types of coatings. In this work we used a stainless steel plasma reactor to grow thin polymeric films from low pressure RF excited plasma of diethylene glycol dimethyl ether. Plasmas were generated at 5W RF power in the range of 16 Pa to 60 Pa. The molecular structure of plasma polymerized films and their optical properties were analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet-Visible Spectroscopy, respectively. The IR spectra show C-H stretching at 3000-2900 cm{sup -1}, C=O stretching at 1730-1650 cm{sup -1}, C-H bending at 1440-1380 cm{sup -1}, C-O and C-O-C stretching at 1200-1000 cm{sup -1}. The refraction index was around 1.5 and the optical gap calculated from absorption coefficient presented value near 3.8 eV. Water contact angle of the films ranged from 40 deg. to 35 deg. with corresponding surface energy from 66 to 73x10{sup -7} J. Because of its favorable optical and hydrophilic characteristics these films can be used in ophthalmic industries as glass lenses coatings.

  2. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike

    2008-01-01

    , external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous......In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode...... plasma. In this study, we are presenting the surface modification"pf polymers by plasma polymerization using Softplasma™. Softplasma™ can be used for two major types of polymerization: polymerization of vinyl monomers, where plasma acts as initiator; chemical vapour deposition, where plasma acts...

  3. Study of RF-excited Diethylene Glycol Dimethyl Ether Plasmas by Mass Spectrometry

    International Nuclear Information System (INIS)

    Algatti, M A; Mota, R P; Júnior, P W P Moreira; Honda, R Y; Kayama, M E; Kostov, K G

    2012-01-01

    This paper deals with the study of the fragmentation process of diethylene glycol dimethyl ether (CH 3 O(CH 2 CH 2 O) 2 CH 3 ) (diglyme here in) molecule in low pressure RF excited plasma discharges. The study was carried out using mass spectrometry. The results showed that for a fixed pressure, the increase of the RF power coupled to the plasma chamber from 1 to 35 W produced a plasma environment much more reactive which increases the population of the ionized species like CH 2 + (15 amu), C 2 H 4 + (28 amu), CH 3 O + (31 amu), C 2 H 4 O + (44 amu), CH 3 OCH 2 CH 2 + (59 amu) and CH 3 OCH 2 CH 2 O + (75 amu). This fact may be attributed to the increase of the electronic temperature that makes predominant the occurrence of inelastic processes that promotes molecular fragmentation. For a fixed value of RF power the increase of pressure from 50 mTorr to 100 mTorr produces the decreasing of the above mentioned chemical species due the lower electronic mean free path. These results suggest that if one wants to keep the monomer's functionality within the plasma deposited films resulting from such kind of discharges one must operate in low power conditions.

  4. Reformulating Polycaprolactone Fumarate to Eliminate Toxic Diethylene Glycol: Effects of Polymeric Branching and Autoclave Sterilization on Material Properties

    Science.gov (United States)

    Runge, M. Brett; Wang, Huan; Spinner, Robert J; Windebank, Anthony J; Yaszemski, Michael J.

    2011-01-01

    Polycaprolactone fumarate (PCLF) is a cross-linkable derivate of polycaprolactone diol that has been shown to be an effective nerve conduit material that supports regeneration across segmental nerve defects and has warranted future clinical trials. Degradation of the previously studied PCLF (PCLFDEG) releases toxic small molecules of diethylene glycol used as the initiator for the synthesis of polycaprolactone diol. In an effort to eliminate this toxic degradation product we present a strategy for the synthesis of PCLF from either propylene glycol (PCLFPPD) or glycerol (PCLFGLY). PCLFPPD is linear and resembles the previously studied PCLFDEG, while PCLFGLY is branched and exhibits dramatically different material properties. The synthesis and characterization of their thermal, rheological, and mechanical properties are reported. The results show that the linear PCLFPPD has material properties similar to the previously studied PCLFDEG. The branched PCLFGLY exhibits dramatically lower crystalline properties resulting in lower rheological and mechanical moduli, and is therefore a more compliant material. In addition, the question of an appropriate FDA approvable sterilization method is addressed. This study shows that autoclave sterilization on PCLF materials is an acceptable sterilization method for cross-linked PCLF and has minimal effect on the PCLF thermal and mechanical properties. PMID:21911087

  5. Reverse-osmosis membranes by plasma polymerization

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T.

    1972-01-01

    Thin allyl amine polymer films were developed using plasma polymerization. Resulting dry composite membranes effectively reject sodium chloride during reverse osmosis. Films are 98% sodium chloride rejective, and 46% urea rejective.

  6. Prediction of two-sample 99mTc-diethylene triamine pentaacetic acid plasma clearance from single-sample method

    International Nuclear Information System (INIS)

    Zuo Li; Ma Ying-Chun; Wang Mei; Zhang Chun-Li; Wang Rong-Fu; Wang Hai-Yan

    2005-01-01

    The objective of this study was to develop an equation to predict dual plasma sample method (DPSM) 99m Tc-diethylene triamine pentaacetic acid ( 99m Tc-DTPA) plasma clearance from single plasma sample method (SPSM), and to clarify the condition in which DPSM can be substituted by SPSM in measurement of glomerular filtration rate (GFR). Patients with chronic kidney disease (CKD) were selected. Watson modified Christensen and Groth equation was used to calculate 99m Tc-DTPA plasma clearance by SPSM (sGFR). The equation recommended by the Nephrourology Committee of the Society of Nuclear Medicine was used to calculate 99m Tc-DTPA plasma clearance by DPSM (tGFR) in each patient. The difference between sGFR and tGFR was expressed as percent of the average of these two methods, and tGFR was predicted from sGFR. Plasma creatinine was measured by the kinetic picrate method, and GFR estimated by abbreviated modification of diet in renal disease (MDRD) equation (aGFR) and Cockcroft-Gault equation (cGFR) were evaluated as criteria in selection of DPSM and SPSM. Three hundred and sixty-nine patients with CKD were selected (208 male and 161 female). The average age and body weight were 51.4±15.5 years and 67.2±12.5 kg, respectively. The causes of CKD were glomerular disease, renal arterial stenosis, chronic tubulointerstitial disease, and other causes or causes unknown. The average tGFR was 62.9±36.5 ml/min/1.73 m 2 , ranging from 1-180 ml/min/1.73 m 2 . sGFR was significantly correlated with tGFR (r=0.9194, p 2 ; in contrast, then tGFR was±30 ml/min/1.73 m 2 , the difference was constant (-1.1%, 95% confidence interval -18.3%, 16.1%), and tGFR could be predicted from sGFR using the equation: predicted tGFR (ml/min/1.73 m 2 )=7 4244+0.7318 x sGFR+0.0022 x sGFR 2 (n=299, r 2 =0.9428, p 2 , the diagnostic sensitivity of a cut off value of aGFR=45 ml/min/1.73 m 2 was 91.8%, and recommended as a criterion in the selection of DPSM and SPSM. When GFR ≥30 ml/min/1.73 m 2 , t

  7. A new lithography of functional plasma polymerized thin films

    International Nuclear Information System (INIS)

    Kim, Sung-O

    2001-01-01

    The preparation of the resist for the vacuum lithography was carried out by plasma polymerization. The resist manufactured by plasma polymerization is a monomer produced by MMA (Methyl methacrylate). The functional groups of MMA appeared in the PPMMA (Plasma Polymerized Methyl methacrylate) as well, and this was confirmed through an analysis using FT-IR. The polymerization rate increased as a function of the plasma power and decreased as a function of the system pressure. The sensitivity and contrast of the plasma polymerized thin films were 15 μC/cm2 and 4.3 respectively. The size of the pattern manufactured by Vacuum Lithography using the plasma polymerized thin films was 100 nm

  8. Plasma etching of electrospun polymeric nanofibres

    Energy Technology Data Exchange (ETDEWEB)

    Verdonck, Patrick [LSI-PSI-EPUSP, Av. Prof. Luciano Gualberto trav 3, 158, 05508-900 Sao Paulo, SP (Brazil)]. E-mail: verdonck@imec.be; Braga Caliope, Priscila [LSI-PSI-EPUSP, Av. Prof. Luciano Gualberto trav 3, 158, 05508-900 Sao Paulo, SP (Brazil); Moral Hernandez, Emilio del [LSI-PSI-EPUSP, Av. Prof. Luciano Gualberto trav 3, 158, 05508-900 Sao Paulo, SP (Brazil); Silva, Ana Neilde R. da [LSI-PSI-EPUSP, Av. Prof. Luciano Gualberto trav 3, 158, 05508-900 Sao Paulo, SP (Brazil); FATEC-SP, Pca Fernando Prestes, 30 Sao Paulo, SP (Brazil)

    2006-10-25

    Electrospun polymeric nanofibres have several applications because of their high surface area to volume and high length to diameter ratios. This paper investigates the influence of plasma etching on these fibres and the etching mechanisms. For the characterization, SEM analysis was performed to determine the forms and shapes of the fibres and SEM photos were analysed by the technique of mathematical morphology, in order to determine the area on the sample occupied by the fibres and the frequency distribution of the nanofibre diameters. The results showed that the oxygen plasma etches the nanofibres much faster when ion bombardment is present. The form of the fibres is not altered by the etching, indicating the possibility of transport of oxygen atoms over the fibre surface. The most frequent diameter, somewhat surprisingly, is not significantly dependent on the etching process, and remains of the order of 80 nm, indicating that fibres with smaller diameters are etched at high rates.

  9. Variables and advantages of the polymerization process in plasma

    International Nuclear Information System (INIS)

    Rojas, Andres F; Ortiz, Jairo A; Restrepo, Elizabeth; Devia Alfonso

    1998-01-01

    They are given to know the parameters that affect the polymerization process in plasma like they are: the kinetics, the electric joining, the variables related to the substrata and the interaction plasma/surface. Some advantages of the polymerization process are also presented with regard to the conventional processes

  10. Polymerization by plasma: surface treatment and plasma simulation

    International Nuclear Information System (INIS)

    Morales C, J.

    2001-01-01

    One of the general objectives that are developed by the group of polymers semiconductors in the laboratory of polymers of the UAM-Iztapalapa is to study the surface treatment for plasma of different materials. Framed in this general objective, in this work three lines of investigation have been developed, independent one of other that converge in the general objective. The first one tries about the modeling one and evaluation of the microscopic parameters of operation of the polymerization reactor. The second are continuation of the study of conductive polymers synthesized by plasma and the third are an application of the treatment for plasma on natural fibers. In the first one it lines it is carried out the characterization and simulation of the parameters of operation of the polymerization reactor for plasma. They are determined the microscopic parameters of operation of the reactor experimentally like they are the electronic temperature, the potential of the plasma and the density average of electrons using for it an electrostatic Langmuir probe. In the simulation, starting from the Boltzmann transport equation it thinks about the flowing pattern and the electronic temperature, the ions density is obtained and of electrons. The data are compared obtained experimentally with the results of the simulation. In second line a study is presented about the influence of the temperature on the electric conductivity of thin films doped with iodine, of poly aniline (P An/I) and poly pyrrole (P Py/I). The films underwent heating-cooling cycles. The conductivity of P An/I and P Py/I in function of the temperature it is discussed based on the Arrhenius model, showing that it dominates the model of homogeneous conductivity. It is also synthesized a polymer bi-layer of these two elements and a copolymer random poly aniline-poly pyrrole, of the first one it the behavior of its conductivity discusses with the temperature and of the second, the conductivity is discussed in

  11. Polyurethane coating with thin polymer films produced by plasma polymerization of diglyme

    International Nuclear Information System (INIS)

    Ribeiro, M A; Ramos, A S; Manfredini, M I; Alves, H A; Ramos, E C T; Honda, R Y; Kostov, K G; Lucena, E F; Mota, R P; Algatti, M A; Kayama, M E

    2009-01-01

    Aqueous-based polyurethane dispersions have been widely utilized as lubricants in textile, shoes, automotive, biomaterial and many other industries because they are less aggressive to surrounding environment. In this work thin films with different thickness were deposited on biocompatible polyurethane by plasma polymerization process using diethylene glycol dimethyl ether (Diglyme) as monomer. Molecular structure of the films was analyzed by Fourier Transform Infrared spectroscopy. The spectra exhibited absorption bands of O-H (3500-3200cm -1 ), C-H (3000-2900cm -1 ), C=O (1730-1650cm -1 ), C-O and C-O-C bonds at 1200-1600cm -1 . The samples wettability was evaluated by measurements of contact angle using different liquids such as water, glycerol, poly-ethane and CMC. The polyurethane surface showed hydrophilic behavior after diglyme plasma-deposition with contact angle dropping from 85 deg. to 22 deg. Scanning Electron Microscopy revealed that diglyme films covered uniformly the polyurethane surfaces ensuring to it a biocompatible characteristic.

  12. Polyurethane coating with thin polymer films produced by plasma polymerization of diglyme

    Science.gov (United States)

    Ribeiro, M. A.; Ramos, A. S.; Manfredini, M. I.; Alves, H. A.; Y Honda, R.; Kostov, K. G.; Lucena, E. F.; Ramos, E. C. T.; Mota, R. P.; Algatti, M. A.; Kayama, M. E.

    2009-05-01

    Aqueous-based polyurethane dispersions have been widely utilized as lubricants in textile, shoes, automotive, biomaterial and many other industries because they are less aggressive to surrounding environment. In this work thin films with different thickness were deposited on biocompatible polyurethane by plasma polymerization process using diethylene glycol dimethyl ether (Diglyme) as monomer. Molecular structure of the films was analyzed by Fourier Transform Infrared spectroscopy. The spectra exhibited absorption bands of O-H (3500-3200cm-1), C-H (3000-2900cm-1), C=O (1730-1650cm-1), C-O and C-O-C bonds at 1200-1600cm-1. The samples wettability was evaluated by measurements of contact angle using different liquids such as water, glycerol, poly-ethane and CMC. The polyurethane surface showed hydrophilic behavior after diglyme plasma-deposition with contact angle dropping from 85° to 22°. Scanning Electron Microscopy revealed that diglyme films covered uniformly the polyurethane surfaces ensuring to it a biocompatible characteristic.

  13. Polyurethane coating with thin polymer films produced by plasma polymerization of diglyme

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, M A; Ramos, A S; Manfredini, M I; Alves, H A; Ramos, E C T [UNIVAP, Sao Jose dos Campos, SP (Brazil); Honda, R Y; Kostov, K G; Lucena, E F; Mota, R P; Algatti, M A; Kayama, M E, E-mail: rmota@feg.unesp.b [FEG-DFQ-UNESP, Av. Ariberto Pereira da Cunha 333, 12516-410 - Guaratingueta, SP (Brazil)

    2009-05-01

    Aqueous-based polyurethane dispersions have been widely utilized as lubricants in textile, shoes, automotive, biomaterial and many other industries because they are less aggressive to surrounding environment. In this work thin films with different thickness were deposited on biocompatible polyurethane by plasma polymerization process using diethylene glycol dimethyl ether (Diglyme) as monomer. Molecular structure of the films was analyzed by Fourier Transform Infrared spectroscopy. The spectra exhibited absorption bands of O-H (3500-3200cm{sup -1}), C-H (3000-2900cm{sup -1}), C=O (1730-1650cm{sup -1}), C-O and C-O-C bonds at 1200-1600cm{sup -1}. The samples wettability was evaluated by measurements of contact angle using different liquids such as water, glycerol, poly-ethane and CMC. The polyurethane surface showed hydrophilic behavior after diglyme plasma-deposition with contact angle dropping from 85 deg. to 22 deg. Scanning Electron Microscopy revealed that diglyme films covered uniformly the polyurethane surfaces ensuring to it a biocompatible characteristic.

  14. Novel polymer coatings based on plasma polymerized 2-methoxyethyl acrylate

    DEFF Research Database (Denmark)

    Wu, Zhenning; Jiang, Juan; Benter, Maike

    2008-01-01

    plasma system[4]. The system named SoftPlasma™ is equipped with unique three-phase pulsed AC voltage. Low energy plasma polymerization has almost no thermal load for sensitive polymer materials[5]. Plasma polymerized coatings are highly cross-linked, pin-hole free and provide hydrophilic or hydrophobic...... properties[4-6]. We have exploited these possibilities and prepared plasma polymerized 2-methoxyethyl acrylate (PPMEA) coatings on various polymer substrates. The PPMEA coatings were optimized using various plasma polymerization conditions and characterized by X-ray photoelectron spectroscopy......, Fouriertransform infrared spectroscopy, Atomic force spectroscopy and Water contact-angle measurements. The microstructures ofPPMEA coatings with different thicknesses were also studied. For practical applications in mind, the coating stability was tested in different media (air, water, acetone, phosphate...

  15. Properties of amine-containing coatings prepared by plasma polymerization

    Czech Academy of Sciences Publication Activity Database

    Choukourov, A.; Biederman, H.; Kholodkov, I.; Slavínská, D.; Trchová, Miroslava; Hollander, A.

    2004-01-01

    Roč. 92, č. 2 (2004), s. 979-990 ISSN 0021-8995 R&D Projects: GA MŠk ME 554 Institutional research plan: CEZ:AV0Z4050913 Keywords : plasma polymerization * thin films * functionalization Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.021, year: 2004

  16. Plasma polymerized high energy density dielectric films for capacitors

    Science.gov (United States)

    Yamagishi, F. G.

    1983-01-01

    High energy density polymeric dielectric films were prepared by plasma polymerization of a variety of gaseous monomers. This technique gives thin, reproducible, pinhole free, conformable, adherent, and insoluble coatings and overcomes the processing problems found in the preparation of thin films with bulk polymers. Thus, devices are prepared completely in a vacuum environment. The plasma polymerized films prepared all showed dielectric strengths of greater than 1000 kV/cm and in some cases values of greater than 4000 kV/cm were observed. The dielectric loss of all films was generally less than 1% at frequencies below 10 kHz, but this value increased at higher frequencies. All films were self healing. The dielectric strength was a function of the polymerization technique, whereas the dielectric constant varied with the structure of the starting material. Because of the thin films used (thickness in the submicron range) surface smoothness of the metal electrodes was found to be critical in obtaining high dielectric strengths. High dielectric strength graft copolymers were also prepared. Plasma polymerized ethane was found to be thermally stable up to 150 C in the presence of air and 250 C in the absence of air. No glass transitions were observed for this material.

  17. Modeling the chemistry of plasma polymerization using mass spectrometry.

    Science.gov (United States)

    Ihrig, D F; Stockhaus, J; Scheide, F; Winkelhake, Oliver; Streuber, Oliver

    2003-04-01

    The goal of the project is a solvent free painting shop. The environmental technologies laboratory is developing processes of plasma etching and polymerization. Polymerized thin films are first-order corrosion protection and primer for painting. Using pure acetylene we get very nice thin films which were not bonded very well. By using air as bulk gas it is possible to polymerize, in an acetylene plasma, well bonded thin films which are stable first-order corrosion protections and good primers. UV/Vis spectroscopy shows nitrogen oxide radicals in the emission spectra of pure nitrogen and air. But nitrogen oxide is fully suppressed in the presence of acetylene. IR spectroscopy shows only C=O, CH(2) and CH(3) groups but no nitrogen species. With the aid of UV/Vis spectra and the chemistry of ozone formation it is possible to define reactive traps and steps, molecule depletion and processes of proton scavenging and proton loss. Using a numerical model it is possible to evaluate these processes and to calculate theoretical mass spectra. Adjustment of theoretical mass spectra to real measurements leads to specific channels of polymerization which are driven by radicals especially the acetyl radical. The estimated theoretical mass spectra show the specific channels of these chemical processes. It is possible to quantify these channels. This quantification represents the mass flow through this chemical system. With respect to these chemical processes it is possible to have an idea of pollutant production processes.

  18. Polythiophene films obtained by polymerization under atmospheric pressure plasma conditions

    Energy Technology Data Exchange (ETDEWEB)

    Teslaru, T.; Topala, I., E-mail: ionut.topala@uaic.ro; Dobromir, M.; Pohoata, V.; Curecheriu, L.; Dumitrascu, N.

    2016-02-01

    The present work describes the experimental arrangement used to initiate polymerization reactions of thiophene monomer based on a dielectric barrier discharge with plane – parallel geometry, working at atmospheric pressure in argon, in turn to obtain conductive polymeric films for different applications. The resulting plasma polymerized polythiophene (pPTh) film was characterized by FT-IR, UV–Vis, XPS spectroscopy, AFM and contact angle measurements. Characterization of pPTh films showed a higher hydrophobic character and roughness, as compared with films obtained by chemical methods, and the thickness is depending on polymerization duration. Also it can conclude that our samples represent oxidised state of pPTh. As a possible application, it analysed in situ the iodine absorption phenomenon in the pPTh matrix and its time evolution by UV–Vis spectroscopy. The presence of iodine 3d{sub 5/2} and 3d{sub 3/2} peaks in the pPTh sample after absorption was identified by XPS spectroscopy. The hydrophobic pPTh film is transformed in a super hydrophilic film after absorption of iodine vapors. - Highlights: • We obtained polythiophene films (pPTh) by atmospheric pressure plasma technique. • The pPTh films showed a hydrophobic character and conducting properties. • The pPTh films were used as sensor for iodine vapors in biological environment.

  19. Method of preparing water purification membranes. [polymerization of allyl amine as thin films in plasma discharge

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T. J., Jr. (Inventor)

    1974-01-01

    Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.

  20. Plasma polymerization at different positions in an asymmetric ethylene discharge

    International Nuclear Information System (INIS)

    Trieschmann, Jan; Hegemann, Dirk

    2011-01-01

    The characteristics of plasma polymerization are investigated in an asymmetric, capacitively coupled plasma discharge. Here, the deposition in different plasma zones, i.e. on the driven electrode, within the plasma bulk and the plasma sheath as well as approximately at the plasma-sheath edge, is investigated. Principal expectations are perfectly met, though new interesting dependences of the obtained a-C : H coatings with respect to film properties and deposition rates are also found. That is, the deposition rates as measured on thin, small glass slides placed directly on the electrode are considerably higher than everywhere else in the plasma, yet only single-sided. In contrast, the deposition rates on the samples within the plasma are lowered depending on the exact placement, while a double-sided coating is obtained. Furthermore, film properties, such as the film density, are highly dependent on the sample placement in the plasma, which can even be higher under floating conditions. With simple physical arguments we are able to show the relations between the deposition rate and the energy input into the plasma as well as between the energy density during film growth and the film density itself.

  1. A plasma polymerization technique to overcome cerebrospinal fluid shunt infections

    Energy Technology Data Exchange (ETDEWEB)

    Coekeliler, D [Plasma Aided Bioengineering and Biotechnology Research Laboratory, Engineering Faculty, Hacettepe University, 06532, Ankara (Turkey); Caner, H [Department of Neurosurgery, School of Medicine, Baskent University, 06610, Ankara (Turkey); Zemek, J [Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, 162 53, Prague, Czech Republic (Czech Republic); Choukourov, A [Department of Macromolecular Physics, Charles University, V Holesovickach 2, 18000 Prague (Czech Republic); Biederman, H [Department of Macromolecular Physics, Charles University, V Holesovickach 2, 18000 Prague (Czech Republic); Mutlu, M [Plasma Aided Bioengineering and Biotechnology Research Laboratory, Engineering Faculty, Hacettepe University, 06532, Ankara (Turkey)

    2007-03-01

    Prosthetic devices, mainly shunts, are frequently used for temporary or permanent drainage of cerebrospinal fluid. The pathogenesis of shunt infection is a very important problem in modern medicine and generally this is characterized by staphylococcal adhesion to the cerebrospinal fluid shunt surfaces. In this paper, the prevention of the attachment of test microorganism Staphylococcus epidermidis on the cerebrospinal fluid shunt surfaces by 2-hydroxyethylmethacrylate (HEMA) precursor modification in the plasma polymerization system, is reported. Different plasma polymerization conditions (RF discharge power 10-20-30 W, exposure time 5-10-15 min) were employed during the surface modification. The surface chemistry and topology of unmodified and modified shunts was characterized by x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also, static contact angle measurements were performed to state the change of surface hydrophilicity. All samples were tested in vitro with Staphylococcus epidermidis. A plasma-polymerized HEMA film (PP HEMA) was found to be an alternative simple method to decrease the microorganism attachment and create bacterial anti-fouling surfaces. The attachment of the model microorganism Staphylococcus epidermidis on the shunt surface modified by PP HEMA at 20 W and 15 min was reduced 62.3% if compared to the unmodified control surface of the shunt.

  2. Composite plasma polymerized sulfonated polystyrene membrane for PEMFC

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Bhabesh Kumar; Khan, Aziz; Chutia, Joyanti, E-mail: jchutiaiasst@gmail.com

    2015-10-15

    Highlights: • Methyl methane sulfonate (MMS) is used as the sulfonating agent. • The proton conductivity of the membrane is found to be 0.141 S cm{sup −1}. • Power density of fuel cell with styrene/MMS membrane is 0.5 W cm{sup −2}. • The membrane exhibits thermal stability up to 140 °C. - Abstract: This work presents the introduction of an organic compound methyl methane sulfonate (MMS) for the first time in fabrication of polystyrene based proton exchange membrane (PEM) by plasma polymerization process. The membrane is fabricated by co-polymerizing styrene and MMS in capacitively coupled continuous RF plasma. The chemical composition of the plasma polymerized polymer membrane is investigated using Fourier Transform Infrared Spectroscopy which reveals the formation of composite structure of styrene and MMS. The surface morphology studied using AFM and SEM depicts the effect of higher partial pressure of MMS on surface topography of the membrane. The proton transport property of the membrane studied using electrochemical impedance spectroscopy shows the achievement of maximum proton conductivity of 0.141 S cm{sup −1} which is comparable to Nafion 117 membrane. Fuel cell performance test of the synthesized membrane shows a maximum power density of 500 mW cm{sup −2} and current density of 0.62 A cm{sup −2} at 0.6 V.

  3. Immobilization of biomolecules to plasma polymerized pentafluorophenyl methacrylate.

    Science.gov (United States)

    Duque, Luis; Menges, Bernhard; Borros, Salvador; Förch, Renate

    2010-10-11

    Thin films of plasma polymerized pentafluorophenyl methacrylate (pp-PFM) offer highly reactive ester groups throughout the structure of the film that allow for subsequent reactions with different aminated reagents and biological molecules. The present paper follows on from previous work on the plasma deposition of pentafluorophenyl methacrylate (PFM) for optimum functional group retention (Francesch, L.; Borros, S.; Knoll, W.; Foerch, R. Langmuir 2007, 23, 3927) and reactivity in aqueous solution (Duque, L.; Queralto, N.; Francesch, L.; Bumbu, G. G.; Borros, S.; Berger, R.; Förch, R. Plasma Process. Polym. 2010, accepted for publication) to investigate the binding of a biologically active peptide known to induce cellular adhesion (IKVAV) and of biochemically active proteins such as BSA and fibrinogen. Analyses of the films and of the immobilization of the biomolecules were carried out using infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The attachment of the biomolecules on pulsed plasma polymerized pentafluorophenyl methacrylate was monitored using surface plasmon resonance spectroscopy (SPR). SPR analysis confirmed the presence of immobilized biomolecules on the plasma polymer and was used to determine the mass coverage of the peptide and proteins adsorbed onto the films. The combined analysis of the surfaces suggests the covalent binding of the peptide and proteins to the surface of the pp-PFM.

  4. Controlling the Plasma-Polymerization Process of N-Vinyl-2-pyrrolidone

    DEFF Research Database (Denmark)

    Norrman, Kion; Winther-Jensen, Bjørn

    2005-01-01

    N-vinyl-2-pyrrolidone was plasma-polymerized on glass substrates using a pulsed AC plasma. Pulsed AC plasma produces a chemical surface structure different from that produced by conventional RF plasma; this is ascribed to the different power regimes used. A high degree of control over the structure...... of the chemical surface was obtained using pulsed AC plasma, as shown by ToF-SIMS. It is demonstrated how the experimental conditions to some extent control the chemical structure of the plasma-polymerized film, e.g., film thickness, density of post-plasma-polymerized oligomeric chains, and the density of intact...

  5. Characteristics of polyimide-based composite membranes fabricated by low-temperature plasma polymerization

    International Nuclear Information System (INIS)

    Dung Thi Tran; Mori, Shinsuke; Suzuki, Masaaki

    2008-01-01

    Composite membranes were prepared by the deposition of plasma-polymerized allylamine films onto a porous polyimide substrate. The relationship between the plasma conditions and the membrane characteristics was described in terms of monomer flow rate, plasma discharge power, plasma polymerization time, and so on. Scanning electron microscope (SEM) images indicate that the thickness of the plasma polymer layer increased and the membrane skin pore size decreased gradually with the increasing of plasma polymerization time. Fourier transform infrared (FTIR) spectra demonstrate the appearance of amine groups in the plasma deposited polymer and the contact angle measurements indicate that the hydrophilicity of the membrane surfaces increased significantly after plasma polymerization. The composite membranes can reject salt from sodium chloride feed solution, and membrane separation performance depends strongly on the plasma conditions applied during the preparation of the plasma deposited polymer films

  6. Surface modification of nanoporous alumina membranes by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Losic, Dusan; Cole, Martin A; Dollmann, Bjoern; Vasilev, Krasimir; Griesser, Hans J [Ian Wark Research Institute, University of South Australia, Mawson Lakes, Adelaide, SA 5095 (Australia)], E-mail: dusan.losic@unisa.edu.au

    2008-06-18

    The deposition of plasma polymer coatings onto porous alumina (PA) membranes was investigated with the aim of adjusting the surface chemistry and the pore size of the membranes. PA membranes from commercial sources with a range of pore diameters (20, 100 and 200 nm) were used and modified by plasma polymerization using n-heptylamine (HA) monomer, which resulted in a chemically reactive polymer surface with amino groups. Heptylamine plasma polymer (HAPP) layers with a thickness less than the pore diameter do not span the pores but reduce their diameter. Accordingly, by adjusting the deposition time and thus the thickness of the plasma polymer coating, it is feasible to produce any desired pore diameter. The structural and chemical properties of modified membranes were studied by scanning electron microscopy (SEM), atomic force microscopy (AFM) and x-ray electron spectroscopy (XPS). The resultant PA membranes with specific surface chemistry and controlled pore size are applicable for molecular separation, cell culture, bioreactors, biosensing, drug delivery, and engineering complex composite membranes.

  7. Surface modification of nanoporous alumina membranes by plasma polymerization

    International Nuclear Information System (INIS)

    Losic, Dusan; Cole, Martin A; Dollmann, Bjoern; Vasilev, Krasimir; Griesser, Hans J

    2008-01-01

    The deposition of plasma polymer coatings onto porous alumina (PA) membranes was investigated with the aim of adjusting the surface chemistry and the pore size of the membranes. PA membranes from commercial sources with a range of pore diameters (20, 100 and 200 nm) were used and modified by plasma polymerization using n-heptylamine (HA) monomer, which resulted in a chemically reactive polymer surface with amino groups. Heptylamine plasma polymer (HAPP) layers with a thickness less than the pore diameter do not span the pores but reduce their diameter. Accordingly, by adjusting the deposition time and thus the thickness of the plasma polymer coating, it is feasible to produce any desired pore diameter. The structural and chemical properties of modified membranes were studied by scanning electron microscopy (SEM), atomic force microscopy (AFM) and x-ray electron spectroscopy (XPS). The resultant PA membranes with specific surface chemistry and controlled pore size are applicable for molecular separation, cell culture, bioreactors, biosensing, drug delivery, and engineering complex composite membranes

  8. Polymerization of phenol by using discharged plasma under hydrothermal state

    Energy Technology Data Exchange (ETDEWEB)

    Mitsugi, M; Yoshida, A; Watanabe, H; Kiyan, T; Takade, M; Miyaji, K; Kuwahara, Y; Akiyama, H; Hara, M; Sasaki, M [Graduate School of Science and Technology, Kumamoto University (Japan); Namihira, T; Goto, M, E-mail: mgoto@kumamoto-u.ac.j [Bioelectrics Research Center, Kumamoto University 2-39-1 Kurokami, Kumamoto 865-8555 Japan (Japan)

    2010-03-01

    Supercritical fluid with plasma is a type of green processing media because this technique does not use catalyst and toxic solvents. In this study, we carried out experiments of organic materials in the presence of discharged plasma in sub- and supercritical water to evaluate the possibility for new reactions. For this purpose, we used SUS316 reactor that generates plasma at temperature and pressure up to 573K and 30MPa, respectively. 100 mmol/L aqueous phenol solution was used as starting material. The reactions were carried out at temperature of 523K and under pressure of 25MPa. After a series of reactions, water-soluble, water-insoluble (oily products), solid residue and gaseous product were obtained. For the analysis of these products, HPLC, GC-MS, TOC, GC-TCD and TOF-MS were used. The highest phenol conversion was 16.96% obtained at 523K, 25MPa and with 4000 times discharged plasma. Polymerized phenol was obtained as a product.

  9. Polymerization of phenol by using discharged plasma under hydrothermal state

    International Nuclear Information System (INIS)

    Mitsugi, M; Yoshida, A; Watanabe, H; Kiyan, T; Takade, M; Miyaji, K; Kuwahara, Y; Akiyama, H; Hara, M; Sasaki, M; Namihira, T; Goto, M

    2010-01-01

    Supercritical fluid with plasma is a type of green processing media because this technique does not use catalyst and toxic solvents. In this study, we carried out experiments of organic materials in the presence of discharged plasma in sub- and supercritical water to evaluate the possibility for new reactions. For this purpose, we used SUS316 reactor that generates plasma at temperature and pressure up to 573K and 30MPa, respectively. 100 mmol/L aqueous phenol solution was used as starting material. The reactions were carried out at temperature of 523K and under pressure of 25MPa. After a series of reactions, water-soluble, water-insoluble (oily products), solid residue and gaseous product were obtained. For the analysis of these products, HPLC, GC-MS, TOC, GC-TCD and TOF-MS were used. The highest phenol conversion was 16.96% obtained at 523K, 25MPa and with 4000 times discharged plasma. Polymerized phenol was obtained as a product.

  10. Ultrasmooth plasma polymerized coatings for laser-fusion targets

    International Nuclear Information System (INIS)

    Letts, S.A.; Myers, D.W.; Witt, L.A.

    1980-01-01

    Coatings for laser fusion targets were deposited up to 135 μm thick by plasma polymerization onto 140 μm diameter DT filled glass microspheres. Ultrasmooth surfaces (no defect higher than 0.1 μm) were achieved by eliminating particulate contamination. Process generated particles were eliminated by determining the optimum operating conditions of power, gas flow, and pressure, and maintaining these conditions through feedback control. From a study of coating defects grown over known surface irregularities, a quantitative relationship between irregularity size, film thickness, and defect size was determined. This relationship was used to set standards for the maximum microshell surface irregularity tolerable in the production of hydrocarbon or fluorocarbon coated laser fusion targets

  11. Ultrasmooth plasma polymerized coatings for laser fusion targets

    International Nuclear Information System (INIS)

    Letts, S.A.; Myers, D.W.; Witt, L.A.

    1980-01-01

    Coatings for laser fusion were deposited up to 135μm thick by plasma polymerization onto 140 μm diameter DT filled glass microspheres. Ultrasmooth surfaces (no defect higher than 0.1 μm) were achieved by eliminating particulate contamination. Process generated particles were eliminated by determining the optimum operating conditions of power (20 watts), gas flow (0.3 sccm trans-2-butene, 10.0 sccm hydrogen), and pressure (75 millitorr), and maintaining these conditions through feedback control. From a study of coating defects grown over known surface irregularities, a quantitative relationship between irregularity size, film thickness, and defect size was determined. This relationship was used to set standards for the maximum microshell surface irregularity tolerable in the production of hydrocarbon or fluorocarbon coated laser fusion targets

  12. Initial biocompatibility of plasma polymerized hexamethyldisiloxane films with different wettability

    Science.gov (United States)

    Krasteva, N. A.; Toromanov, G.; Hristova, K. T.; Radeva, E. I.; Pecheva, E. V.; Dimitrova, R. P.; Altankov, G. P.; Pramatarova, L. D.

    2010-11-01

    Understanding the relationships between material surface properties, behaviour of adsorbed proteins and cellular responses is essential to design optimal material surfaces for tissue engineering. In this study we modify thin layers of plasma polymerized hexamethyldisiloxane (PPHMDS) by ammonia treatment in order to increase surface wettability and the corresponding biological response. The physico-chemical properties of the polymer films were characterized by contact angle (CA) measurements and Fourier Transform Infrared Spectroscopy (FTIR) analysis.Human umbilical vein endothelial cells (HUVEC) were used as model system for the initial biocompatibility studies following their behavior upon preadsorption of polymer films with three adhesive proteins: fibronectin (FN), fibrinogen (FG) and vitronectin (VN). Adhesive interaction of HUVEC was evaluated after 2 hours by analyzing the overall cell morphology, and the organization of focal adhesion contacts and actin cytoskeleton. We have found similar good cellular response on FN and FG coated polymer films, with better pronounced vinculin expression on FN samples while. Conversely, on VN coated surfaces the wettability influenced significantly initial celular interaction spreading. The results obtained suggested that ammonia plasma treatment can modulate the biological activity of the adsorbed protein s on PPHMDS surfaces and thus to influence the interaction with endothelial cells.

  13. Optical characterization of composite layers prepared by plasma polymerization

    International Nuclear Information System (INIS)

    Radeva, E; Hikov, T; Mitev, D; Pramatarova, L; Stroescu, H; Nicolescu, M; Gartner, M; Presker, R

    2016-01-01

    Thin composite layers from polymer/nanoparticles (Ag-nanoparticles and detonation nanodiamonds) were prepared by plasma polymerization process on the base of hexamethyldisiloxane. The variation of the layer composition was achieved by changing the type of nanoparticles. The optical measurement techniques used were UV-VIS-NIR ellipsometry (SE), Fourier-transformed infrared spectroscopy (FTIR) and Raman spectroscopy. The values of the refractive index determined are in the range 1.30 to 1.42. All samples are transparent with transmission between 85-95% and very smooth. The change in Raman and FTIR spectra of the composites verify the expected bonding between polymer and diamond nanoparticles due to the penetration of the fillers in the polymer matrix. The comparison of the spectra of the corresponding NH3 plasma treated composites revealed that the composite surface becomes more hydrophilic. The obtained results indicate that preparation of layers with desired compositions is possible at a precise control of the detonation nanodiamond materials. (paper)

  14. THE KINETICS OF METHYL METHACRYLATE POLYMERIZATION INITIATED BY THE VOLATILE PRODUCTS OF A METHYL METHACRYLATE PLASMA

    Institute of Scientific and Technical Information of China (English)

    杨梅林; 马於光; 郑莹光; 沈家骢

    1990-01-01

    It is found that the volatile products of methyl methacrylate plasma can very actively initiate the polymerization of the monomer to produce ultrahigh molecular weight polymers. This polymerization of MMA occurs by a livlng free radical mechanism with instantaneous initiation and monomer transfer.

  15. Plasma-polymerized alkaline anion-exchange membrane: Synthesis and structure characterization

    International Nuclear Information System (INIS)

    Hu Jue; Meng Yuedong; Zhang Chengxu; Fang Shidong

    2011-01-01

    After-glow discharge plasma polymerization was developed for alkaline anion-exchange membranes synthesis using vinylbenzyl chloride as monomer. X-ray photoelectron spectroscopy and attenuated total reflection Fourier transform infrared spectroscopy were used to characterize the chemical structure properties of plasma-polymerized membranes. Ion-exchange capacities of quaternized poly(vinylbenzyl chloride) (QPVBC) membranes were measured to evaluate their capability of hydroxyl ion transport. A mechanism of plasma polymerization using VBC as monomer that accounts for the competitive effects of free radicals polymerization and plasma ablation in the plasma polymerization process was proposed. Our results indicate that plasma discharge power influences the contents of functional groups and the structure of the plasma polymer membranes, which attribute to the coactions of polymerization and ablation. The properties of uniform morphology, good adhesion to the substrate, high thermal stability and satisfying anion conduction level suggest the potential application of QPVBC membrane deposited at discharge power of 20 W in alkaline direct methanol fuel cells.

  16. Micro patterning of cell and protein non-adhesive plasma polymerized coatings for biochip applications

    DEFF Research Database (Denmark)

    Bouaidat, Salim; Berendsen, C.; Thomsen, P.

    2004-01-01

    Micro scale patterning of bioactive surfaces is desirable for numerous biochip applications. Polyethyleneoxide-like (PEO-like) coating with non-fouling functionality has been deposited using low frequency AC plasma polymerization. The non-fouling properties of the coating were tested with human c...... and versatility of the plasma-polymerized coatings, make this technology highly suitable for bio-MEMS and biochip applications, where patterned high contrast non-fouling surfaces are needed....

  17. Plasma-polymerized hexamethyldisilazane treated by nitrogen plasma immersion ion implantation technique

    Energy Technology Data Exchange (ETDEWEB)

    Honda, R Y; Mota, R P; Batocki, R G S; Santos, D C R; Nicoleti, T; Kostov, K G; Kayama, M E; Algatti, M A [Laboratorio de Plasma, Faculdade de Engenharia, UNESP, Av. Dr Ariberto Pereira da Cunha-333, 12516-410, Guaratingueta, SP (Brazil); Cruz, N C [Laboratorio de Plasmas Tecnologicos, Unidade Diferenciada, UNESP, Av. Tres de Marco-511, 18085-180, Sorocaba, SP (Brazil); Ruggiero, L, E-mail: honda@feg.unesp.b [Faculdade de Ciencias, UNESP, Av. Luis E. Carrijo Coube 14-1, 17033-360, Bauru, SP (Brazil)

    2009-05-01

    This paper describes the effect of nitrogen Plasma Immersion Ion Implantation (PIII) on chemical structure, refraction index and surface hardness of plasma-polymerized hexamethyldisilazane (PPHMDSN) thin films. Firstly, polymeric films were deposited at 13.56 MHz radiofrequency (RF) Plasma Enhanced Chemical Vapour Deposition (PECVD) and then, were treated by nitrogen PIII from 15 to 60 min. Fourier Transformed Infrared (FTIR) spectroscopy was employed to analyse the molecular structure of the samples, and it revealed that vibrations modes at 3350 cm{sup -1}, 2960 cm{sup -1}, 1650 cm{sup -1}, 1250 cm{sup -1} and 1050 cm{sup -1} were altered by nitrogen PIII. Visible-ultraviolet (vis-UV) spectroscopy was used to evaluate film refractive index and the results showed a slight increase from 1.6 to 1.8 following the implantation time. Nanoindentation revealed a surface hardness rise from 0.5 to 2.3 GPa as PIII treatment time increased. These results indicate nitrogen PIII is very promising in improving optical and mechanical properties of PPHMDSN films.

  18. The influence of pulse parameters on film composition during pulsed plasma polymerization of diaminocyclohexane

    Czech Academy of Sciences Publication Activity Database

    Choukourov, A.; Biederman, H.; Slavínská, D.; Trchová, Miroslava; Hollander, A.

    174-175, - (2003), s. 863-866 ISSN 0257-8972. [International Conference on Plasma Surface Engineering /8./. Garmisch-Partenkirchen, 09.09.2002-13.09.2002] R&D Projects: GA AV ČR KSK4050111 Keywords : plasma polymerization * chemical derivation * primary and secondary amino groups Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.410, year: 2003

  19. Vapor phase reactions in polymerization plasma for divinylsiloxane-bis-benzocyclobutene film deposition

    International Nuclear Information System (INIS)

    Kinoshita, Keizo; Nakano, Akinori; Kawahara, Jun; Kunimi, Nobutaka; Hayashi, Yoshihiro; Kiso, Osamu; Saito, Naoaki; Nakamura, Keiji; Kikkawa, Takamaro

    2006-01-01

    Vapor phase reactions in plasma polymerization of divinylsiloxane-bis-benzocyclobutene (DVS-BCB) low-k film depositions on 300 mm wafers were studied using mass spectrometry, in situ Fourier transform infrared, and a surface wave probe. Polymerization via Diels-Alder cycloaddition reaction was identified by the detection of the benzocyclohexene group. Hydrogen addition and methyl group desorption were also detected in DVS-BCB monomer and related large molecules. The dielectric constant k of plasma polymerized DVS-BCB with a plasma source power range up to 250 W was close to ∼2.7 of thermally polymerized DVS-BCB, and increased gradually over 250 W. The electron density at 250 W was about 1.5x10 10 cm -3 . The increase of the k value at higher power was explained by the decrease of both large molecular species via multistep dissociation and incorporation of silica components into the polymer. It was found that the reduction of electron density as well as precursor residence time is important for the plasma polymerization process to prevent the excess dissociation of the precursor

  20. Amine Enrichment of Thin-Film Composite Membranes via Low Pressure Plasma Polymerization for Antimicrobial Adhesion.

    Science.gov (United States)

    Reis, Rackel; Dumée, Ludovic F; He, Li; She, Fenghua; Orbell, John D; Winther-Jensen, Bjorn; Duke, Mikel C

    2015-07-15

    Thin-film composite membranes, primarily based on poly(amide) (PA) semipermeable materials, are nowadays the dominant technology used in pressure driven water desalination systems. Despite offering superior water permeation and salt selectivity, their surface properties, such as their charge and roughness, cannot be extensively tuned due to the intrinsic fabrication process of the membranes by interfacial polymerization. The alteration of these properties would lead to a better control of the materials surface zeta potential, which is critical to finely tune selectivity and enhance the membrane materials stability when exposed to complex industrial waste streams. Low pressure plasma was employed to introduce amine functionalities onto the PA surface of commercially available thin-film composite (TFC) membranes. Morphological changes after plasma polymerization were analyzed by SEM and AFM, and average surface roughness decreased by 29%. Amine enrichment provided isoelectric point changes from pH 3.7 to 5.2 for 5 to 15 min of plasma polymerization time. Synchrotron FTIR mappings of the amine-modified surface indicated the addition of a discrete 60 nm film to the PA layer. Furthermore, metal affinity was confirmed by the enhanced binding of silver to the modified surface, supported by an increased antimicrobial functionality with demonstrable elimination of E. coli growth. Essential salt rejection was shown minimally compromised for faster polymerization processes. Plasma polymerization is therefore a viable route to producing functional amine enriched thin-film composite PA membrane surfaces.

  1. Study on the role of active radicals on plasma sterilization inside small diameter flexible polymeric tubes

    Science.gov (United States)

    Mstsuura, Hiroto; Fujiyama, Takatomo; Okuno, Yasuki; Furuta, Masakazu; Okuda, Shuichi; Takemura, Yuichiro

    2015-09-01

    Recently, atmospheric pressure discharge plasma has gathered attention in various fields. Among them, plasma sterilization with many types of plasma source has studied for decades and its mechanism is still an open question. If active radicals produced in plasma has main contribution of killing bacterias, direct contact of the so-called plasma flame might not be necessary. To confirm this, sterilization inside small diameter flexible polymeric tubes is studied in present work. DBD type plasma jet is produce by flowing helium gas in a glass tube. A long polymeric tube is connected and plasma jet is introduced into it. Plasma flame length depends on helium gas flow rate, but limited to about 10 cm in our experimental condition. E.colis set at the exit plasma source is easily killed during 10 min irradiation. At the tube end (about 20 cm away from plasma source exit), sterilization is possible with 30 min operation. This result shows that active radical is produced with helium plasma and mist contained in sample, and it can be transferred more than 20 cm during it life time. More plasma diagnostic data will also be shown at the conference. This work was partially supported by the ''ZE Research Program, IAE(ZE27B-4).

  2. Antifouling coatings via plasma polymerization and atom transfer radical polymerization on thin film composite membranes for reverse osmosis

    Science.gov (United States)

    Hirsch, Ulrike; Ruehl, Marco; Teuscher, Nico; Heilmann, Andreas

    2018-04-01

    A major drawback to otherwise highly efficient membrane-based desalination techniques like reverse osmosis (RO) is the susceptibility of the membranes to biofouling. In this work, a combination of plasma activation, plasma bromination and surface-initiated atom transfer radical polymerization (si-ATRP) of hydrophilic and zwitterionic monomers, namely hydroxyethyl methacrylate (HEMA), 2-methacryloyloxyethyl phosphorylcholine (MPC) and [2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA), was applied to generate non-specific, anti-adhesive coatings on thin film composite (TFC) membranes. The antifouling effect of the coatings was shown by short-time batch as well as long-time steady state cultivation experiments with the microorganism Pseudomonas fluorescens. It could be shown that plasma functionalization and polymerization is possible on delicate thin film composite membranes without restricting their filtration performance. All modified membranes showed an increased resistance towards the adhesion of Pseudomonas fluorescens. On average, the biofilm coverage was reduced by 51.4-12.6% (for HEMA, SBMA, and MPC), the highest reduction was monitored for MPC with a biofilm reduction by 85.4%. The hydrophilic coatings applied did not only suppress the adhesion of Pseudomonas fluorescens, but also significantly increase the permeate flux of the membranes relative to uncoated membranes. The stability of the coatings was however not ideal and will have to be improved for future commercial use.

  3. Immobilization and controlled release of drug using plasma polymerized thin film

    Energy Technology Data Exchange (ETDEWEB)

    Myung, Sung-Woon [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju (Korea, Republic of); Jung, Sang-Chul [Department of Environmental Engineering, Sunchon National University, Sunchon 540-742 (Korea, Republic of); Kim, Byung-Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju (Korea, Republic of)

    2015-06-01

    In this study, plasma polymerization of acrylic acid was employed to immobilize drug and control its release. Doxorubicin (DOX) was immobilized covalently on the glass surface deposited with plasma polymerized acrylic acid (PPAAc) thin film containing the carboxylic group. At first, the PPAAc thin film was coated on a glass surface at a pressure of 1.33 Pa and radio frequency (RF) discharge power of 20 W for 10 min. DOX was immobilized on the PPAAc deposition in a two environment of phosphate buffer saline (PBS) and dimethyl sulfoxide (DMSO) solutions. The DOX immobilized surface was characterized by scanning electron microscope, atomic force microscope and attenuated total reflection Fourier transform infrared spectroscopy. The DOX molecules were more immobilized in PBS than DMSO solution. The different immobilization and release profiles of DOX result from the solubility of hydrophobic DOX in aqueous and organic solutions. Second, in order to control the release of the drug, PPAAc thin film was covered over DOX dispersed layer. Different thicknesses and cross-linked PPAAc thin films by adjusting deposition time and RF discharge power were covered on the DOX layer dispersed. PPAAc thin film coated DOX layer reduced the release rate of DOX. The thickness control of plasma deposition allows controlling the release rate of drug. - Highlights: • Doxorubicin was immobilized on the surface of plasma polymerized acrylic acid thin film. • Release profile of doxorubicin was affected by aqueous and organic solutions. • Plasma polymerized acrylic acid thin film can be used to achieve controlled release.

  4. Immobilization and controlled release of drug using plasma polymerized thin film

    International Nuclear Information System (INIS)

    Myung, Sung-Woon; Jung, Sang-Chul; Kim, Byung-Hoon

    2015-01-01

    In this study, plasma polymerization of acrylic acid was employed to immobilize drug and control its release. Doxorubicin (DOX) was immobilized covalently on the glass surface deposited with plasma polymerized acrylic acid (PPAAc) thin film containing the carboxylic group. At first, the PPAAc thin film was coated on a glass surface at a pressure of 1.33 Pa and radio frequency (RF) discharge power of 20 W for 10 min. DOX was immobilized on the PPAAc deposition in a two environment of phosphate buffer saline (PBS) and dimethyl sulfoxide (DMSO) solutions. The DOX immobilized surface was characterized by scanning electron microscope, atomic force microscope and attenuated total reflection Fourier transform infrared spectroscopy. The DOX molecules were more immobilized in PBS than DMSO solution. The different immobilization and release profiles of DOX result from the solubility of hydrophobic DOX in aqueous and organic solutions. Second, in order to control the release of the drug, PPAAc thin film was covered over DOX dispersed layer. Different thicknesses and cross-linked PPAAc thin films by adjusting deposition time and RF discharge power were covered on the DOX layer dispersed. PPAAc thin film coated DOX layer reduced the release rate of DOX. The thickness control of plasma deposition allows controlling the release rate of drug. - Highlights: • Doxorubicin was immobilized on the surface of plasma polymerized acrylic acid thin film. • Release profile of doxorubicin was affected by aqueous and organic solutions. • Plasma polymerized acrylic acid thin film can be used to achieve controlled release

  5. Surface Modification of Polymeric Materials by Plasma Treatment

    Directory of Open Access Journals (Sweden)

    E.F. Castro Vidaurre

    2002-03-01

    Full Text Available Low-temperature plasma treatment has been used in the last years as a useful tool to modify the surface properties of different materials, in special of polymers. In the present work low temperature plasma was used to treat the surface of asymmetric porous substrates of polysulfone (PSf membranes. The main purpose of this work was to study the influence of the exposure time and the power supplied to argon plasma on the permeability properties of the membranes. Three rf power levels, respectively 5, 10 and 15 W were used. Treatment time ranged from 1 to 50 min. Reduction of single gas permeability was observed with Ar plasma treatments at low energy bombardment (5 W and short exposure time (20 min. Higher power and/or higher plasma exposition time causes a degradation process begins. The chemical and structural characterization of the membranes before and after the surface modification was done by AFM, SEM and XPS.

  6. Modification of glass fibers to improve reinforcement: a plasma polymerization technique

    Czech Academy of Sciences Publication Activity Database

    Çökeliler, D.; Erkut, S.; Zemek, Josef; Biederman, H.; Mutlu, M.

    2007-01-01

    Roč. 23, č. 3 (2007), s. 335-342 ISSN 0109-5641 Institutional research plan: CEZ:AV0Z10100521 Keywords : plasma polymerization * glos-discharge * E-glass fibros * ethylendiamine * 2-hydroxyethyl methacrystalate * triethyleneglycoldimethylether * fibre-reinforced composite ( FRC) Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.990, year: 2007

  7. Polymerization by plasma of trichloroethylene by means of resistive and inductive coupling

    International Nuclear Information System (INIS)

    Vasquez, M.; Cruz, G.; Olayo, M.G.; Timoshina, T.; Morales, J.; Olayo, R.

    2004-01-01

    It was carried out the polymerization for plasma of the trichloroethylene by means of two types of coupling, resistive and inductive with the objective of studying the structure, morphology and the electric properties of the polymers obtained under these conditions. The structure and morphology of the polymers were studied by means of EDS and FT-IR spectroscopies. (Author)

  8. Plasma polymerization coating of D-T filled glass shells for laser fusion targets

    International Nuclear Information System (INIS)

    Johnson, W.L.; Hatcher, C.W.; Hendricks, C.D.; Letts, S.A.; Lorensen, L.E.

    1977-01-01

    Three plasma sources are described which activate monomers of perfluoro-2-butene or tetrafluoroethylene to produce coatings 10 to 20 μm thick with surfaces finishes <0.1 μm. Electrical and chemical controls of the polymerization processes are shown to improve the surface finish

  9. Elimination of defects in plasma polymerized films used in laser fusion targets

    International Nuclear Information System (INIS)

    Letts, S.A.; Johnson, W.L.; Myers, D.W.; Illige, J.D.; Lorensen, L.E.; Hatcher, C.W.

    1979-01-01

    This study was conducted to understand and control the parameters governing the formation of defects in plasma polymerized surfaces. An inductively-coupled discharge was used as the source of activated monomer. Four types of well characterized surface irregularities were produced on glass slides which were subsequently fluorocarbon coated. Optimization of the process variables is discussed

  10. Plasma polymerization surface modification of Carbon black and its effect in elastomers

    NARCIS (Netherlands)

    Mathew, T.; Datta, Rabin; Dierkes, Wilma K.; Talma, Auke; Ooij, W.J.; Noordermeer, Jacobus W.M.

    2011-01-01

    Surface modification of carbon black by plasma polymerization was aimed to reduce its surface energy in order to compatibilize the filler with various elastomers. A fullerenic carbon black was used for the modification process. Thermogravimetric analysis, wetting behavior with liquids of known

  11. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    Science.gov (United States)

    Zhang, Huanxia; Li, Wei

    2015-11-01

    Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid-base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as Csbnd O, Cdbnd O, and Osbnd Cdbnd O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the plasma-grafting treatments.

  12. Immobilization/hybridization of amino-modified DNA on plasma-polymerized allyl chloride

    International Nuclear Information System (INIS)

    Zhang Zhihong; Feng Chuanliang

    2007-01-01

    The present work describes the fabrication and characterization of chloride-derivatized polymer coatings prepared by continuous wave (cw) plasma polymerization as adhesion layers in DNA immobilization/hybridization. The stability of plasma-polymerized allyl chloride (ppAC) in H 2 O was characterized by variation of the thickness of polymer films and its wettability was examined by water contact angle technique. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to study polymer matrix properties and oligonucleotide/DNA binding interaction. With the same carrier gas rate and process pressure, plasma polymers deposited at different input powers show various comparable immobilization properties; nevertheless, low input power plasma-polymerized films gives a lower sensitivity toward DNA binding than that from high input power plasma-deposited films. The following DNA immobilization on chloride-functionalized surfaces was found dependence on the macromolecular architecture of the plasma films. The hybridization between probe DNA and total mismatch target DNA shows no non-specific adsorption between target and ppAC

  13. Modulation of release kinetics by plasma polymerization of ampicillin-loaded β -TCP ceramics

    International Nuclear Information System (INIS)

    Labay, C; Buxadera-Palomero, J; Avilés, M; Canal, C; Ginebra, M P

    2016-01-01

    Beta-tricalcium phosphate ( β -TCP) bioceramics are employed in bone repair surgery. Their local implantation in bone defects puts them in the limelight as potential materials for local drug delivery. However, obtaining suitable release patterns fitting the required therapeutics is a challenge. Here, plasma polymerization of ampicillin-loaded β -TCP is studied for the design of a novel antibiotic delivery system. Polyethylene glycol-like (PEG-like) coating of β -TCP by low pressure plasma polymerization was performed using diglyme as precursor, and nanometric PEG-like layers were obtained by simple and double plasma polymerization processes. A significant increase in hydrophobicity, and the presence of plasma polymer was visible on the surface by SEM and quantified by XPS. As a main consequence of the plasma polymerisation, the release kinetics were successfully modified, avoiding burst release, and slowing down the initial rate of release leading to a 4.5 h delay in reaching the same antibiotic release percentage, whilst conservation of the activity of the antibiotic was simultaneously maintained. Thus, plasma polymerisation on the surface of bioceramics may be a good strategy to design controlled drug delivery matrices for local bone therapies. (paper)

  14. The Effect of Plasma Surface Treatment on a Porous Green Ceramic Film with Polymeric Binder Materials

    International Nuclear Information System (INIS)

    Yun Jeong Woo

    2013-01-01

    To reduce time and energy during thermal binder removal in the ceramic process, plasma surface treatment was applied before the lamination process. The adhesion strength in the lamination films was enhanced by oxidative plasma treatment of the porous green ceramic film with polymeric binding materials. The oxygen plasma characteristics were investigated through experimental parameters and weight loss analysis. The experimental results revealed the need for parameter analysis, including gas material, process time, flow rate, and discharge power, and supported a mechanism consisting of competing ablation and deposition processes. The weight loss analysis was conducted for cyclic plasma treatment rather than continuous plasma treatment for the purpose of improving the film's permeability by suppressing deposition of the ablated species. The cyclic plasma treatment improved the permeability compared to the continuous plasma treatment.

  15. Review of some research work on surface modification and polymerizations by non-equilibrium plasma in Turkey

    International Nuclear Information System (INIS)

    Akovali, Guneri

    2004-01-01

    Non equilibrium plasma studies in Turkey can be considered as organized on two different lines: surface modification studies and plasma polymerization studies. Plasma surface modification studies: In different laboratories in Turkey the modification of materials' surfaces by plasma covers a wide spectra, for example: fibers (Carbon (CF) and polyacrylonitrile (PAN)), fabrics (PET/Cotton and PET/PA), biomaterials-food oriented (PU), denture Acrylic matrix, plasmochemical modification of a (PE and PP) film surface by several selected silicon and tin containing monomers, polymer blends and composites, recycled rubber and epoxy systems, etc. Plasma polymerization studies: This topic is accomplished by a great number of projects, for instance: plasma initiation polymerization and copolymerization of Styrene and MMA, Plasma-initiated polymerizations of Acrylamide (AA), kinetics of polymer deposition of several selected saturated hydrocarbons, silanization treatments by hexamethyldisilazane (HDMS), Plasma initiated polymerization (PIP) of allyl alcohol and 1-propano, (PSP) and (PIP) studies related to activated charcoal are done to explore their applications in haemoperfusion, an amperometric alcohol single-layer electrode is prepared by (EDA) plasma polymerization, preparation of mass sensitive immuno sensors and single layer multi enzyme electrodes by plasma polymerisation technique, etc

  16. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Huanxia, E-mail: zhanghuanxia818@163.com [College of Materials and Textile Engineering, Jiaxing University, Jiaxing 314001, Zhejiang (China); Li, Wei [College of Textile Engineering, Donghua University, Shanghai 201620 (China); Key Laboratory of Textile Science and Technology, Ministry of Education, Shanghai 201620 (China)

    2015-11-30

    Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

  17. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    International Nuclear Information System (INIS)

    Zhang, Huanxia; Li, Wei

    2015-01-01

    Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

  18. Evaluation of Osseointegration of Titanium Alloyed Implants Modified by Plasma Polymerization

    Directory of Open Access Journals (Sweden)

    Carolin Gabler

    2014-02-01

    Full Text Available By means of plasma polymerization, positively charged, nanometre-thin coatings can be applied to implant surfaces. The aim of the present study was to quantify the adhesion of human bone cells in vitro and to evaluate the bone ongrowth in vivo, on titanium surfaces modified by plasma polymer coatings. Different implant surface configurations were examined: titanium alloy (Ti6Al4V coated with plasma-polymerized allylamine (PPAAm and plasma-polymerized ethylenediamine (PPEDA versus uncoated. Shear stress on human osteoblast-like MG-63 cells was investigated in vitro using a spinning disc device. Furthermore, bone-to-implant contact (BIC was evaluated in vivo. Custom-made conical titanium implants were inserted at the medial tibia of female Sprague-Dawley rats. After a follow-up of six weeks, the BIC was determined by means of histomorphometry. The quantification of cell adhesion showed a significantly higher shear stress for MG-63 cells on PPAAm and PPEDA compared to uncoated Ti6Al4V. Uncoated titanium alloyed implants showed the lowest BIC (40.4%. Implants with PPAAm coating revealed a clear but not significant increase of the BIC (58.5% and implants with PPEDA a significantly increased BIC (63.7%. In conclusion, plasma polymer coatings demonstrate enhanced cell adhesion and bone ongrowth compared to uncoated titanium surfaces.

  19. A state-of-the-art plasma polymerization coater for ICF targets

    International Nuclear Information System (INIS)

    Devine, G.; Letts, S.; Cook, R.; Brusasco, R.

    1992-01-01

    Increasingly stringent demands on the characteristics of plasma polymer coatings for use in Inertial Confinement Fusion (ICF) experiments have created a need for a plasma Polymerization coating system with the capability of producing a wide variety of different types of coatings as well as one that can be used to do fundamental investigations of the process conditions leading to desirable films. We report on the construction and use of just such a coating instrument. We have recognized the usefulness of computer assisted process monitoring and control, currently being developed by the semiconductor industry, in designing our own, State-of-the-art plasma polymerization device. Our system is fully computer interfaced to provide the user with the capability of collecting system parameter data over the length of the deposition experiment. The system is also designed to allow for any degree of computer control of the deposition process in the future

  20. Characterization and properties of plasma polymerized 2-vinylpyridine

    International Nuclear Information System (INIS)

    Bieg, K.W.; Ottesen, D.K.; Brower, K.L.

    1979-11-01

    The chemical structure, aging, thermal, and adhesive behavior of plasma-deposited 2-vinylpyridine has been investigated. The molecular structure of the plasma polymer is significantly different from the conventional, linear polymer and is strongly dependent on plasma reactor variables. Additional cyano, methyl, and olefinic groups were identified in the plasma polymer, and aromaticity retention was reduced at the more severe (low pressure, high rf power) reactor conditions studied. Post-deposition oxidation occurred, which followed approximately first order kinetics initially (ΔE approx. 11.6 Kcal/mole, with approx. 25% conversion of aromatic rings to an aromatic ketone in 4.5 months at 23 0 C). Oxidation was significantly reduced in vacuum, inert gas, and hydrogen atmospheres. Thermal weight loss began at relatively low temperatures and appeared to accompany an exothermic, irreversible cross-linking reaction which began at about 100 0 C. Principle low temperature decomposition products were low molecular weight gases (primarily, CO 2 ) and 2-methylpyridine. A quantitative tensile-pull adhesion test was developed. Using this technique, the plasma polymer-aluminum cohesive bond strength was found to be 480 psi and was degraded at high humidity levels

  1. Hydrophobic Coatings on Cotton Obtained by in Situ Plasma Polymerization of a Fluorinated Monomer in Ethanol Solutions.

    Science.gov (United States)

    Molina, Ricardo; Teixidó, Josep Maria; Kan, Chi-Wai; Jovančić, Petar

    2017-02-15

    Plasma polymerization using hydrophobic monomers in the gas phase is a well-known technology to generate hydrophobic coatings. However, synthesis of functional hydrophobic coatings using plasma technology in liquids has not yet been accomplished. This work is consequently focused on polymerization of a liquid fluorinated monomer on cotton fabric initiated by atmospheric plasma in a dielectric barrier discharge configuration. Functional hydrophobic coatings on cotton were successfully achieved using in situ atmospheric plasma-initiated polymerization of fluorinated monomer dissolved in ethanol. Gravimetric measurements reveal that the amount of polymer deposited on cotton substrates can be modulated with the concentration of monomer in ethanol solution, and cross-linking reactions occur during plasma polymerization of a fluorinated monomer even without the presence of a cross-linking agent. FTIR and XPS analysis were used to study the chemical composition of hydrophobic coatings and to get insights into the physicochemical processes involved in plasma treatment. SEM analysis reveals that at high monomer concentration, coatings possess a three-dimensional pattern with a characteristic interconnected porous network structure. EDX analysis reveals that plasma polymerization of fluorinated monomers takes place preferentially at the surface of cotton fabric and negligible polymerization takes place inside the cotton fabric. Wetting time measurements confirm the hydrophobicity of cotton coatings obtained although equilibrium moisture content was slightly decreased. Additionally, the abrasion behavior and resistance to washing of plasma-coated cotton has been evaluated.

  2. Grafting of molecularly imprinted polymer to porous polyethylene filtration membranes by plasma polymerization.

    Science.gov (United States)

    Cowieson, D; Piletska, E; Moczko, E; Piletsky, S

    2013-08-01

    An application of plasma-induced grafting of polyethylene membranes with a thin layer of molecularly imprinted polymer (MIP) was presented. High-density polyethylene (HDPE) membranes, "Vyon," were used as a substrate for plasma grafting modification. The herbicide atrazine, one of the most popular targets of the molecular imprinting, was chosen as a template. The parameters of the plasma treatment were optimized in order to achieve a good balance between polymerization and ablation processes. Modified HDPE membranes were characterized, and the presence of the grafted polymeric layer was confirmed based on the observed weight gain, pore size measurements, and infrared spectrometry. Since there was no significant change in the porosity of the modified membranes, it was assumed that only a thin layer of the polymer was introduced on the surface. The experiments on the re-binding of the template atrazine to the membranes modified with MIP and blank polymers were performed. HDPE membranes which were grafted with polymer using continuous plasma polymerization demonstrated the best result which was expressed in an imprinted factor equal to 3, suggesting that molecular imprinting was successfully achieved.

  3. Core/shell silicon/polyaniline particles via in-flight plasma-induced polymerization

    International Nuclear Information System (INIS)

    Yasar-Inceoglu, Ozgul; Mangolini, Lorenzo; Zhong, Lanlan

    2015-01-01

    Although silicon nanoparticles have potential applications in many relevant fields, there is often the need for post-processing steps to tune the property of the nanomaterial and to optimize it for targeted applications. In particular surface modification is generally necessary to both tune dispersibility of the particles in desired solvents to achieve optimal coating conditions, and to interface the particles with other materials to realize functional heterostructures. In this contribution we discuss the realization of core/shell silicon/polymer nanoparticles realized using a plasma-initiated in-flight polymerization process. Silicon particles are produced in a non-thermal plasma reactor using silane as a precursor. After synthesis they are aerodynamically injected into a second plasma reactor into which aniline vapor is introduced. The second plasma initiates the polymerization reactor leading to the formation of a 3–4 nm thick polymer shell surrounding the silicon core. The role of processing conditions on the properties of the polymeric shell is discussed. Preliminary results on the testing of this material as an anode for lithium ion batteries are presented. (paper)

  4. Core/shell silicon/polyaniline particles via in-flight plasma-induced polymerization

    Science.gov (United States)

    Yasar-Inceoglu, Ozgul; Zhong, Lanlan; Mangolini, Lorenzo

    2015-08-01

    Although silicon nanoparticles have potential applications in many relevant fields, there is often the need for post-processing steps to tune the property of the nanomaterial and to optimize it for targeted applications. In particular surface modification is generally necessary to both tune dispersibility of the particles in desired solvents to achieve optimal coating conditions, and to interface the particles with other materials to realize functional heterostructures. In this contribution we discuss the realization of core/shell silicon/polymer nanoparticles realized using a plasma-initiated in-flight polymerization process. Silicon particles are produced in a non-thermal plasma reactor using silane as a precursor. After synthesis they are aerodynamically injected into a second plasma reactor into which aniline vapor is introduced. The second plasma initiates the polymerization reactor leading to the formation of a 3-4 nm thick polymer shell surrounding the silicon core. The role of processing conditions on the properties of the polymeric shell is discussed. Preliminary results on the testing of this material as an anode for lithium ion batteries are presented.

  5. Chemistry of plasma-polymerized vinyltriethoxysilane controlled by deposition conditions

    Czech Academy of Sciences Publication Activity Database

    Čech, V.; Zemek, Josef; Peřina, Vratislav

    2008-01-01

    Roč. 5, č. 8 (2008), s. 745-752 ISSN 1612-8850 Grant - others:GAČR(CZ) GA104/06/0437 Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z10480505 Keywords : ESCA/XPS * FTIR * plasma-enhanced chemical vapor deposition (PECVD) * Rutherford back-scattering (RBS) * thin films Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.921, year: 2008

  6. The plasma-polymerized films of dichloro(methyl)phenylsilane

    Czech Academy of Sciences Publication Activity Database

    Čech, V.; Horvath, P.; Zemek, J.; Trchová, M.; Matějková, Jiřina

    2000-01-01

    Roč. 50, Supp. S3 (2000), s. 356-364 ISSN 0011-4626. [Plasma Physics and Technology /10./. Praha, 06.07.2000-09.07.2000] R&D Projects: GA ČR GV106/98/K013; GA ČR GA104/00/0708 Institutional research plan: CEZ:AV0Z2065902 Subject RIV: JR - Other Machinery Impact factor: 0.298, year: 2000

  7. Nanomechanical and nanotribological properties of plasma nanotextured superhydrophilic and superhydrophobic polymeric surfaces

    International Nuclear Information System (INIS)

    Skarmoutsou, A; Charitidis, C A; Gnanappa, A K; Tserepi, A; Gogolides, E

    2012-01-01

    Oxygen plasma-induced surface modification of polymethylmethacrylate (PMMA), under plasma conditions favouring (maximizing) roughness formation, has been shown to create textured surfaces of roughness size and morphology dependent on the plasma-treatment time and subsequent morphology stabilization procedure. Superhydrophobic or superhydrophilic surfaces can thus be obtained, with potential applications in antireflective self-cleaning surfaces, microfluidics, wetting–dewetting control, anti-icing etc, necessitating determination of their mechanical properties. In this study, nanoindentation is used to determine the reduced modulus and hardness of the surface, while nanoscratch tests are performed to measure the coefficient of friction. The data are combined to assess the wear behaviour of such surfaces as a first guide for their practical applications. Short-time plasma treatment slightly changes mechanical, tribological and wear properties compared to untreated PMMA. However, a significant decrease in the reduced modulus and hardness and an increase in the coefficient of friction are observed after long plasma-treatment times. The C 4 F 8 plasma deposited thin hydrophobic layer on the polymeric surfaces (untreated and treated) reveals good adhesion, while its mechanical properties are greatly influenced by the substrate; it is also found that it effectively protects the polymeric surfaces, reducing plastic deformation. (paper)

  8. Penetration enhancer: monoethylether of diethylene glycol

    International Nuclear Information System (INIS)

    Koprda, V.; Kassai, Z.; Bohacik, L.; Bezek, S.; Hadcrafft, J.; Falson-Rieg, F.

    1999-01-01

    The monoethylether of diethylene glycol (Transcutol), an excellent solubilising agent, has been suggested as a penetration enhancer compatible with trans-dermal drug delivery systems. Using the abdominal skin of 5 day old rats and Franz-type diffusion cells the following topics were studied in this contribution: (1) Flux of Transcutol, labelled with [Ethyl- 14 C]-ether, across an intact skin model, (2) Changes in properties of the skin barrier after stripping with adhesive tape, and (3) Changes in flux of Transcutol when mixed with different co-solvents. The flux from pure solvent in donor compartment reached around 50 μg cm -2 hr -1 across the intact skin horny layer, whilst after 12 strips the flux increased about 200 times. In the presence of propylene glycol dipelargonate, the flux over 2 mg cm -2 hr -1 across non stripped skin was achieved. (authors)

  9. Analysis of annealed thin polymer films prepared from dichloro(methyl)phenylsilane by plasma polymerization

    Czech Academy of Sciences Publication Activity Database

    Cech, V.; Horvath, P.; Trchová, M.; Zemek, Josef; Matějková, Jiřina

    2001-01-01

    Roč. 82, - (2001), s. 2106-2112 ISSN 0021-8995 R&D Projects: GA ČR GV106/98/K013; GA ČR GA104/00/0708 Institutional research plan: CEZ:AV0Z1010914 Keywords : plasma polymerization * thin films * thermogravimetric analysis ( TSA ) * FTIR * ESCA/XPS Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.992, year: 2001

  10. The interplay between surface charging and microscale roughness during plasma etching of polymeric substrates

    Science.gov (United States)

    Memos, George; Lidorikis, Elefterios; Kokkoris, George

    2018-02-01

    The surface roughness developed during plasma etching of polymeric substrates is critical for a variety of applications related to the wetting behavior and the interaction of surfaces with cells. Toward the understanding and, ultimately, the manipulation of plasma induced surface roughness, the interplay between surface charging and microscale roughness of polymeric substrates is investigated by a modeling framework consisting of a surface charging module, a surface etching model, and a profile evolution module. The evolution of initially rough profiles during plasma etching is calculated by taking into account as well as by neglecting charging. It is revealed, on the one hand, that the surface charging contributes to the suppression of root mean square roughness and, on the other hand, that the decrease of the surface roughness induces a decrease of the charging potential. The effect of charging on roughness is intense when the etching yield depends solely on the ion energy, and it is mitigated when the etching yield additionally depends on the angle of ion incidence. The charging time, i.e., the time required for reaching a steady state charging potential, is found to depend on the thickness of the polymeric substrate, and it is calculated in the order of milliseconds.

  11. The optical properties of plasma polymerized polyaniline thin films

    Energy Technology Data Exchange (ETDEWEB)

    Goktas, Hilal, E-mail: hilal_goktas@yahoo.com [Canakkale Onsekiz Mart University, Physics Department, 17020 Canakkale (Turkey); Demircioglu, Zahide; Sel, Kivanc [Canakkale Onsekiz Mart University, Physics Department, 17020 Canakkale (Turkey); Gunes, Taylan [Yalova University, Energy Systems Engineering Department, 77100 Yalova (Turkey); Kaya, Ismet [Canakkale Onsekiz Mart University, Chemistry Department, 17020 Canakkale (Turkey)

    2013-12-02

    We report herein the characterizations of polyaniline thin films synthesized using double discharge plasma system. Quartz glass substrates were coated at a pressure of 80 Pa, 19.0 kV pulsed and 1.5 kV dc potential. The substrates were located at different regions in the reactor to evaluate the influence of the position on the morphological and molecular structure of the obtained thin films. The molecular structure of the thin films was investigated by Fourier transform infrared (FTIR) and UV–visible photospectrometers (UV–vis), and the morphological studies were carried out by scanning electron microscope. The FTIR and UV–vis data revealed that the molecular structures of the synthesized thin films were in the form of leuocoemeraldine and exhibited similar structures with the films produced via chemical or electrochemical methods. The optical energy band gap values of the as-grown samples ranged from 2.5 to 3.1 eV, which indicated that these materials have potential applications in semiconductor devices. The refractive index in the transparent region (from 650 to 1000 nm) steadily decreased from 1.9 to 1.4 and the extinction coefficient was found to be on order of 10{sup −4}. The synthesized thin films showed various degrees of granular morphologies depending on the location of the substrate in the reactor. - Highlights: • Polyaniline thin films were synthesized for the first time via double discharge plasma system. • The films have similar structure to that of the chemically synthesized films. • The morphology of the films could be tuned by this technique. • These materials would have potential applications at semiconductor devices.

  12. Synthesis and Characterization of Nanofibrous Polyaniline Thin Film Prepared by Novel Atmospheric Pressure Plasma Polymerization Technique.

    Science.gov (United States)

    Park, Choon-Sang; Kim, Dong Ha; Shin, Bhum Jae; Tae, Heung-Sik

    2016-01-11

    This work presents a study on the preparation of plasma-polymerized aniline (pPANI) nanofibers and nanoparticles by an intense plasma cloud type atmospheric pressure plasma jets (iPC-APPJ) device with a single bundle of three glass tubes. The nano size polymer was obtained at a sinusoidal wave with a peak value of 8 kV and a frequency of 26 kHz under ambient air. Discharge currents, photo-sensor amplifier, and optical emission spectrometer (OES) techniques were used to analyze the plasma produced from the iPC-APPJ device. Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), gas chromatography-mass spectrometry (GC-MS), and gel permeation chromatography (GPC) techniques were used to analyze the pPANI. FE-SEM and TEM results show that pPANI has nanofibers, nanoparticles morphology, and polycrystalline characteristics. The FT-IR and GC-MS analysis show the characteristic polyaniline peaks with evidence that some quinone and benzene rings are broken by the discharge energy. GPC results show that pPANI has high molecular weight ( M w ), about 533 kDa with 1.9 polydispersity index (PDI). This study contributes to a better understanding on the novel growth process and synthesis of uniform polyaniline nanofibers and nanoparticles with high molecular weights using the simple atmospheric pressure plasma polymerization technique.

  13. Synthesis and Characterization of Nanofibrous Polyaniline Thin Film Prepared by Novel Atmospheric Pressure Plasma Polymerization Technique

    Directory of Open Access Journals (Sweden)

    Choon-Sang Park

    2016-01-01

    Full Text Available This work presents a study on the preparation of plasma-polymerized aniline (pPANI nanofibers and nanoparticles by an intense plasma cloud type atmospheric pressure plasma jets (iPC-APPJ device with a single bundle of three glass tubes. The nano size polymer was obtained at a sinusoidal wave with a peak value of 8 kV and a frequency of 26 kHz under ambient air. Discharge currents, photo-sensor amplifier, and optical emission spectrometer (OES techniques were used to analyze the plasma produced from the iPC-APPJ device. Field emission scanning electron microscopy (FE-SEM, transmission electron microscopy (TEM, Fourier transform infrared spectroscopy (FT-IR, gas chromatography-mass spectrometry (GC-MS, and gel permeation chromatography (GPC techniques were used to analyze the pPANI. FE-SEM and TEM results show that pPANI has nanofibers, nanoparticles morphology, and polycrystalline characteristics. The FT-IR and GC-MS analysis show the characteristic polyaniline peaks with evidence that some quinone and benzene rings are broken by the discharge energy. GPC results show that pPANI has high molecular weight (Mw, about 533 kDa with 1.9 polydispersity index (PDI. This study contributes to a better understanding on the novel growth process and synthesis of uniform polyaniline nanofibers and nanoparticles with high molecular weights using the simple atmospheric pressure plasma polymerization technique.

  14. Evaluation of mechanism of cold atmospheric pressure plasma assisted polymerization of acrylic acid on low density polyethylene (LDPE) film surfaces: Influence of various gaseous plasma pretreatment

    Science.gov (United States)

    Ramkumar, M. C.; Pandiyaraj, K. Navaneetha; Arun Kumar, A.; Padmanabhan, P. V. A.; Uday Kumar, S.; Gopinath, P.; Bendavid, A.; Cools, P.; De Geyter, N.; Morent, R.; Deshmukh, R. R.

    2018-05-01

    Owing to its exceptional physiochemical properties, low density poly ethylene (LDPE) has wide range of tissue engineering applications. Conversely, its inadequate surface properties make LDPE an ineffectual candidate for cell compatible applications. Consequently, plasma-assisted polymerization with a selected precursor is a good choice for enhancing its biocompatibility. The present investigation studies the efficiency of plasma polymerization of acrylic acid (AAC) on various gaseous plasma pretreated LDPE films by cold atmospheric pressure plasma, to enhance its cytocompatibility. The change in chemical composition and surface topography of various gaseous plasma pretreated and acrylic deposited LDPE films has been assessed by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The changes in hydrophilic nature of surface modified LDPE films were studied by contact angle (CA) analysis. Cytocompatibility of the AAC/LDPE films was also studied in vitro, using RIN-5F cells. The results acquired by the XPS and AFM analysis clearly proved that cold atmospheric pressure (CAP) plasma assisted polymerization of AAC enhances various surface properties including carboxylic acid functional group density and increased surface roughness on various gaseous plasma treated AAC/LDPE film surfaces. Moreover, contact angle analysis clearly showed that the plasma polymerized samples were hydrophilic in nature. In vitro cytocompatibility analysis undoubtedly validates that the AAC polymerized various plasma pretreated LDPE films surfaces stimulate cell distribution and proliferation compared to pristine LDPE films. Similarly, cytotoxicity analysis indicates that the AAC deposited various gaseous plasma pretreated LDPE film can be considered as non-toxic as well as stimulating cell viability significantly. The cytocompatible properties of AAC polymerized Ar + O2 plasma pretreated LDPE films were found to be more pronounced compared to the other plasma pretreated

  15. Deposition of polymeric perfluored thin films in proton ionic membranes by plasma processes

    International Nuclear Information System (INIS)

    Polak, Peter Lubomir; Mousinho, Ana Paula; Ordonez, Nelson; Silva Zambom, Luis da; Mansano, Ronaldo Domingues

    2007-01-01

    In this work the surfaces of polymeric membranes based on Nafion (proton conducting material), used in proton exchange membranes fuel cells (PEMFC) had been modified by plasma deposition of perfluored polymers, in order to improve its functioning in systems of energy generation (fuel cells). The deposition increases the chemical resistance of the proton ionic polymers without losing the electrical properties. The processing of the membranes also reduces the permeability of the membranes to the alcohols (methanol and ethanol), thus preventing poisoning of the fuel cell. The processing of the membranes of Nafion was carried through in a system of plasma deposition using a mixture of CF 4 and H 2 gases. The plasma processing was made mainly to increase the chemical resistance and result in hydrophobic surfaces. The Fourier transformed infrared (FTIR) technique supplies a spectrum with information about the CF n bond formation. Through the Rutherford back scattering (RBS) technique it was possible to verify the deposition rate of the polymeric layer. The plasma process with composition of 60% of CF 4 and 40% of H 2 presented the best deposition rate. By the spectrum analysis for the optimized configuration, it was possible to verify that the film deposition occurred with a thickness of 90 nm, and fluorine concentration was nearly 30%. Voltammetry made possible to verify that the fluorination increases the membranes chemical resistance, improving the stability of Nafion, becoming an attractive process for construction of fuel cells

  16. Modification of the poly(ethylene) terephthalate track membrane structure and surface in the plasma of non-polymerized gases

    International Nuclear Information System (INIS)

    Kravets, L.I.; Dmitriev, S.N.; Apel, P.Y.

    1999-01-01

    An investigation of the properties of poly(ethylene) terephthalate track membranes (PETTMs) treated with a plasma RF-discharge in non-polymerized gases has been performed. The influence of the plasma treatment conditions on the basic properties of the membranes has been studied. It was arranged that the effect of non-polymerized gases plasma on the PETTMs results to etching a membrane's surface layer. The membranes' pore size and the form in this case change. It is shown that it is possible to change the structure of track membranes directly by gas discharge etching

  17. Studies on surface graft polymerization of acrylic acid onto PTFE film by remote argon plasma initiation

    International Nuclear Information System (INIS)

    Wang Chen; Chen Jierong

    2007-01-01

    The graft polymerization of acrylic acid (AAc) was carried out onto poly(tetrafluoroethylene) (PTFE) films that had been pretreated with remote argon plasma and subsequently exposed to oxygen to create peroxides. Peroxides are known to be the species responsible for initiating the graft polymerization when PTFE reacts with AAc. We chose different parameters of remote plasma treatment to get the optimum condition for introducing maximum peroxides (2.87 x 10 -11 mol/cm 2 ) on the surface. The influence of grafted reaction conditions on the grafting degree was investigated. The maximum grafting degree was 25.2 μg/cm 2 . The surface microstructures and compositions of the AAc grafted PTFE film were characterized with the water contact angle meter, Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). Contact angle measurements revealed that the water contact angle decreased from 108 o to 41 o and the surface free energy increased from 22.1 x 10 -5 to 62.1 x 10 -5 N cm -1 by the grafting of the AAc chains. The hydrophilicity of the PTFE film surface was greatly enhanced. The time-dependent activity of the grafted surface was better than that of the plasma treated film

  18. Stability study of polyacrylic acid films plasma-polymerized on polypropylene substrates at medium pressure

    Energy Technology Data Exchange (ETDEWEB)

    Morent, Rino, E-mail: Rino.Morent@Ugent.be [Department of Applied Physics, Research Unit Plasma Technology, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent (Belgium); De Geyter, Nathalie [Department of Applied Physics, Research Unit Plasma Technology, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent (Belgium); Trentesaux, Martine; Gengembre, Leon [Unite de Catalyse et Chimie du Solide, UMR CNRS 8181, Universite des Sciences et Technologies de Lille, Bat. C3, Cite Scientifique, 59655 Villeneuve d' Ascq (France); Dubruel, Peter [Department of Organic Chemistry, Polymer Chemistry and Biomaterials Research Group, Faculty of Sciences, Ghent University, Krijgslaan 281, 9000 Ghent (Belgium); Leys, Christophe [Department of Applied Physics, Research Unit Plasma Technology, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent (Belgium); Payen, Edmond [Unite de Catalyse et Chimie du Solide, UMR CNRS 8181, Universite des Sciences et Technologies de Lille, Bat. C3, Cite Scientifique, 59655 Villeneuve d' Ascq (France)

    2010-11-01

    Plasma polymerization of acrylic acid has become an interesting research subject, since these coatings are expected to be beneficial for biomedical applications due to their high surface density of carboxylic acid functional groups. However, the application of these monomers is counteracted by their low stability in humid environments, since a high stability is a required characteristic for almost any biological application. The present work investigates whether it is possible to obtain stable deposits with a high retention of carboxylic acid functions by performing plasma polymerization on polypropylene substrates with a dielectric barrier discharge operating at medium pressure. In order to obtain coatings with the desired properties, the plasma parameters need to be optimized. Therefore, in this paper, the influence of discharge power and location of the substrate in the discharge chamber is examined in detail. The properties of the deposited films are studied using contact angle measurements, X-ray photoelectron spectroscopy, atomic force microscopy and Fourier transform infrared spectroscopy. Moreover, to determine whether the obtained deposits are soluble in water, the coatings are once again analyzed after rinsing in water. This paper will clearly show that stable COOH-rich surfaces can be obtained at high discharge power and close to the monomer inlet, which might open perspectives for future biomedical applications.

  19. Morphological, elemental, and optical characterization of plasma polymerized n-butyl methacrylate thin films

    Science.gov (United States)

    Nasrin, Rahima; Hossain, Khandker S.; Bhuiyan, A. H.

    2018-05-01

    Plasma polymerized n-butyl methacrylate (PPnBMA) thin films of varying thicknesses were prepared at room temperature by AC plasma polymerization system using a capacitively coupled parallel plate reactor. Field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), energy-dispersive X-ray (EDX) analysis, and ultraviolet-visible (UV-Vis) spectroscopic investigation have been performed to study the morphological, elemental, and optical properties of the PPnBMA thin films, respectively. The flat and defect-free nature of thin films were confirmed by FESEM and AFM images. With declining plasma power, average roughness and root mean square roughness increase. Allowed direct transition ( E gd) and indirect transition ( E gi) energy gaps were found to be 3.64-3.80 and 3.38-3.45 eV, respectively, for PPnBMA thin films of different thicknesses. Values of E gd as well as E gi increase with the increase of thickness. The extinction coefficient, Urbach energy, and steepness parameter were also determined for these thin films.

  20. Antibacterial performance on plasma polymerized heptylamine films loaded with silver nanoparticles

    Science.gov (United States)

    Lin, Yu-Chun; Lin, Chia-Chun; Lin, Chih-Hao; Wang, Meng-Jiy

    2017-01-01

    The antibacterial performance of the plasma-polymerized (pp) heptylamine thin films loaded with silver nanoparticles was evaluated against the colonization of Escherichia coli and Staphylococcus aureus. The properties including the thickness and chemical composition of the as deposited HApp films were modulated by adjusting plasma parameters. The acquired results showed that the film thickness was controlled in the range of 20 to 400 nm by adjusting deposition time. The subsequent immersion of the HApp thin films in silver nitrate solutions result in the formation of amine-metal complexes, in which the silver nanoparticles were reduced directly on the matrices to form Ag@HApp. The reduction reaction of silver was facilitated by applying NaBH4 as a reducing agent. The results of physicochemical analyses including morphological analysis and ellipsometry revealed that the silver nanoparticles were successfully reduced on the HApp films, and the amount of reduced silver was closely associated which the thickness of the plasma-polymerized films, the concentration of applied metal ions solutions, and the time of immobilization. Regarding the antibacterial performance, the Ag@HApp films reduced by NaBH4 showed antibacterial abilities of 70.1 and 68.2% against E. coli and S. aureus, respectively.

  1. Thin plasma-polymerized layers of hexamethyldisiloxane for humidity sensor development

    International Nuclear Information System (INIS)

    Guermat, N.; Bellel, A.; Sahli, S.; Segui, Y.; Raynaud, P.

    2009-01-01

    The response of resistive-type sensors based on thin hexamethyldisiloxane layers to relative humidity (RH) was evaluated. Humidity sensitive layers were plasma polymerized at low frequency glow discharge using a capacitively coupled parallel plate reactor. The sensor design comprises the absorbing layer deposited on clean glass substrate with comb-shape aluminum electrodes (interdigitated structure). The change in electrical impedance of the sensing film was monitored as the device was exposed to humidity. The variation of the plasma-polymerization parameters resulted in different humidity sensing properties which could be correlated to the results of Fourier transform infrared spectroscopy (FTIR). The deposited films exhibited a detectable response to RH ranging from 30 to 95% with low hysteresis, good reproducibility and stability in long-term use. Films with a greater thickness showed a significant decrease in the humidity sensing capability. FTIR analysis revealed the presence of SiH bonding groups, which are frequently linked to the film density. The increase in the plasma discharge power induced also a significant decrease in the diffusion process of water vapor inside the sensitive layer bulk.

  2. Investigation of the Effect of Plasma Polymerized Siloxane Coating for Enzyme Immobilization and Microfluidic Device Conception

    Directory of Open Access Journals (Sweden)

    Kalim Belhacene

    2016-12-01

    Full Text Available This paper describes the impact of a physical immobilization methodology, using plasma polymerized 1,1,3,3, tetramethyldisiloxane, on the catalytic performance of β-galactosidase from Aspergillus oryzae in a microfluidic device. The β-galactosidase was immobilized by a polymer coating grown by Plasma Enhanced Chemical Vapor Deposition (PEVCD. Combined with a microchannel patterned in the silicone, a microreactor was obtained with which the diffusion through the plasma polymerized layer and the hydrolysis of a synthetic substrate, the resorufin-β-d-galactopyranoside, were studied. A study of the efficiency of the immobilization procedure was investigated after several uses and kinetic parameters of immobilized β-galactosidase were calculated and compared with those of soluble enzyme. Simulation and a modelling approach were also initiated to understand phenomena that influenced enzyme behavior in the physical immobilization method. Thus, the catalytic performances of immobilized enzymes were directly influenced by immobilization conditions and particularly by the diffusion behavior and availability of substrate molecules in the enzyme microenvironment.

  3. Comparative study of nanocomposites prepared by pulsed and dc sputtering combined with plasma polymerization suitable for photovoltaic device applications

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Amreen A. [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Pal, Arup R., E-mail: arpal@iasst.gov.in [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Kar, Rajib [Laser and Plasma Technology Division, Bhabha Atomic Research Center, Trombay, Mumbai (India); Bailung, Heremba; Chutia, Joyanti [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam (India); Patil, Dinkar S. [Laser and Plasma Technology Division, Bhabha Atomic Research Center, Trombay, Mumbai (India)

    2014-12-15

    Plasma processing, a single step method for production of large area composite films, is employed to deposit plasma polymerized aniline-Titanium dioxide (PPani-TiO{sub 2}) nanocomposite thin films. The deposition of PPani-TiO{sub 2} nanocomposite films are made using reactive magnetron sputtering and plasma polymerization combined process. This study focuses on the direct comparison between continuous and pulsed dc magnetron sputtering techniques of titanium in combination with rf plasma polymerization of aniline. The deposited PPani-TiO{sub 2} nanocomposite films are characterized and discussed in terms of structural, morphological and optical properties. A self powered hybrid photodetector has been developed by plasma based process. The proposed method provides a new route where the self-assembly of molecules, that is, the spontaneous association of atomic or molecular building blocks under plasma environment, emerge as a successful strategy to form well-defined structural and morphological units of nanometer dimensions. - Highlights: • PPani-TiO{sub 2} nanocomposite by pulsed and dc sputtering with rf plasma polymerization. • In-situ and Ex-situ H{sub 2}SO{sub 4} doping in PPani-TiO{sub 2} nanocomposite. • PPani-TiO{sub 2} nanocomposite based self-powered-hybrid photodetector.

  4. Comparative study of nanocomposites prepared by pulsed and dc sputtering combined with plasma polymerization suitable for photovoltaic device applications

    International Nuclear Information System (INIS)

    Hussain, Amreen A.; Pal, Arup R.; Kar, Rajib; Bailung, Heremba; Chutia, Joyanti; Patil, Dinkar S.

    2014-01-01

    Plasma processing, a single step method for production of large area composite films, is employed to deposit plasma polymerized aniline-Titanium dioxide (PPani-TiO 2 ) nanocomposite thin films. The deposition of PPani-TiO 2 nanocomposite films are made using reactive magnetron sputtering and plasma polymerization combined process. This study focuses on the direct comparison between continuous and pulsed dc magnetron sputtering techniques of titanium in combination with rf plasma polymerization of aniline. The deposited PPani-TiO 2 nanocomposite films are characterized and discussed in terms of structural, morphological and optical properties. A self powered hybrid photodetector has been developed by plasma based process. The proposed method provides a new route where the self-assembly of molecules, that is, the spontaneous association of atomic or molecular building blocks under plasma environment, emerge as a successful strategy to form well-defined structural and morphological units of nanometer dimensions. - Highlights: • PPani-TiO 2 nanocomposite by pulsed and dc sputtering with rf plasma polymerization. • In-situ and Ex-situ H 2 SO 4 doping in PPani-TiO 2 nanocomposite. • PPani-TiO 2 nanocomposite based self-powered-hybrid photodetector

  5. Mutagenicity testing of diethylene glycol monobutyl ether.

    Science.gov (United States)

    Thompson, E D; Coppinger, W J; Valencia, R; Iavicoli, J

    1984-01-01

    The mutagenic potential of diethylene glycol monobutyl ether (diEGBE) was examined with a Tier I battery of in vitro assays followed by a Tier II in vivo Drosophila sex-linked recessive lethal assay. The in vitro battery consisted of: the Salmonella mutagenicity test, the L5178Y mouse lymphoma test, a cytogenetics assay using Chinese hamster ovary cells and the unscheduled DNA synthesis (UDS) assay in rat hepatocytes. Results of the Salmonella mutagenicity test, the cytogenetics test, and the rat hepatocyte assay were negative at concentrations up to 20 microL/plate, 7.92 microL/mL, and 4.4 microL/mL, respectively. Toxicity was clearly demonstrated at all high doses. A weak, but dose-related increase in the mutation frequency (4-fold increase over the solvent control at 5.6 microL/mL with 12% survival) was obtained in the L5178Y lymphoma test in the absence of metabolic activation. Results of the mouse lymphoma assay were negative in the presence of the S-9 activation system. The significance of the mouse lymphoma assay were negative in the presence of the S-9 activation system. The significance of the mouse lymphoma assay results were assessed by performing the Tier II sex-linked recessive lethal assay in Drosophila in which the target tissue is maturing germinal cells. Both feeding (11,000 ppm for 3 days) and injection (0.3 microL of approximately 14,000 ppm solution) routes of administration were employed in the Drosophila assay. Approximately 11,000 individual crosses with an equal number of negative controls were performed for each route of administration. diEGBE produced no increase in recessive lethals under these conditions.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6389113

  6. Surface modification of polymeric substrates by plasma-based ion implantation

    International Nuclear Information System (INIS)

    Okuji, S.; Sekiya, M.; Nakabayashi, M.; Endo, H.; Sakudo, N.; Nagai, K.

    2006-01-01

    Plasma-based ion implantation (PBII) as a tool for polymer modification is studied. Polymeric films have good performances for flexible use, such as food packaging or electronic devices. Compared with inorganic rigid materials, polymers generally have large permeability for gases and moisture, which causes packaged contents and devices to degrade. In order to add a barrier function, surface of polymeric films are modified by PBII. One of the advantageous features of this method over deposition is that the modified surface does not have peeling problem. Besides, micro-cracks due to mechanical stress in the modified layer can be decreased. From the standpoint of mass production, conventional ion implantation that needs low-pressure environment of less than 10 -3 Pa is not suitable for continuous large-area processing, while PBII works at rather higher pressure of several Pa. In terms of issues mentioned above, PBII is one of the most expected techniques for modification on flexible substrates. However, the mechanism how the barrier function appears by ion implantation is not well explained so far. In this study, various kinds of polymeric films, including polyethyleneterephthalate (PET), are modified by PBII and their barrier characteristics that depend on the ion dose are evaluated. In order to investigate correlations of the barrier function with implanted ions, modified surface is analyzed with X-ray photoelectron spectroscopy (XPS). It is assumed that the diffusion and sorption coefficients are changed by ion implantation, resulting in higher barrier function

  7. Surface modification of polymeric substrates by plasma-based ion implantation

    Science.gov (United States)

    Okuji, S.; Sekiya, M.; Nakabayashi, M.; Endo, H.; Sakudo, N.; Nagai, K.

    2006-01-01

    Plasma-based ion implantation (PBII) as a tool for polymer modification is studied. Polymeric films have good performances for flexible use, such as food packaging or electronic devices. Compared with inorganic rigid materials, polymers generally have large permeability for gases and moisture, which causes packaged contents and devices to degrade. In order to add a barrier function, surface of polymeric films are modified by PBII. One of the advantageous features of this method over deposition is that the modified surface does not have peeling problem. Besides, micro-cracks due to mechanical stress in the modified layer can be decreased. From the standpoint of mass production, conventional ion implantation that needs low-pressure environment of less than 10-3 Pa is not suitable for continuous large-area processing, while PBII works at rather higher pressure of several Pa. In terms of issues mentioned above, PBII is one of the most expected techniques for modification on flexible substrates. However, the mechanism how the barrier function appears by ion implantation is not well explained so far. In this study, various kinds of polymeric films, including polyethyleneterephthalate (PET), are modified by PBII and their barrier characteristics that depend on the ion dose are evaluated. In order to investigate correlations of the barrier function with implanted ions, modified surface is analyzed with X-ray photoelectron spectroscopy (XPS). It is assumed that the diffusion and sorption coefficients are changed by ion implantation, resulting in higher barrier function.

  8. Preparation of germanium doped plasma polymerized coatings as ICF target ablators

    International Nuclear Information System (INIS)

    Brusasco, R.M.; Saculla, M.D.; Cook, R.C.

    1994-01-01

    Targets for Inertial Confinement Fusion (ICF) experiments at the Lawrence Livermore National Laboratory (LLNL) utilize an organic (CH) ablator coating prepared by plasma polymerization. Some of these experiments require a mid-Z dopant in the ablator coating to modify the opacity of the shell. Bromine had been used in the past, but the surface finish of brominated CH degrades rapidly with time upon exposure to air. This paper describes the preparation and characterization of plasma polymer layers containing germanium as a dopant at concentrations of between 1.25 and 2.25 atom percent. The coatings are stable in air and have an rms surface roughness of 7--9 nm (modes 10--1,000) which is similar to that obtained with undoped coatings. High levels of dopant result in cracking of the inner mandrel during target assembly. Possible explanations for the observed cracking behavior will be discussed

  9. Deposition of stable amine coating onto polycaprolactone nanofibers by low pressure cyclopropylamine plasma polymerization

    International Nuclear Information System (INIS)

    Manakhov, Anton; Nečas, David; Čechal, Jan; Pavliňák, David; Eliáš, Marek

    2015-01-01

    Amine-rich films are of high interest for the bio-applications including drug delivery and tissue engineering thanks to their high reactivity allowing the formation of the covalent linkages between biomolecules and a surface. However, the bio-applications of amine-rich films require their good stability in water which is often achieved at large expenses of the amine concentration. Recently, non-toxic cyclopropylamine (CPA) has been applied for the plasma polymerization of films bearing high NH x environment combined with the moderate thickness loss (20%) after water immersion for 48 h. In this work, the amine-rich film with the NH x concentration over 7 at.% was deposited on Si substrates and polycaprolactone nanofiber meshes by using CPA plasma polymerization (pulsed mode) in a vertically oriented stainless steel reactor. The substrates were placed at the radio frequency electrode and the ion bombardment caused by direct-current self-bias was suppressed by using high pressure of 50 Pa. Analysis of samples by scanning electron microscopy did not reveal any cracks in the deposited layer formed during a sample immersion in water. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed a slight oxidation of amine groups in water but the film still contained 5 at.% of NH x (according to the N1s XPS fitting) after the immersion. The rapid oxidation of amine groups was observed during the aging experiment carried out in air at room temperature because FTIR revealed an increase of amide peaks that increased progressively with aging time. However, this oxidation was significantly reduced if the plasma polymer was stored at − 20 °C. Since the films exhibit high amine concentration and very good water stability they have great potential for applications as biocompatible functional coatings. - Highlights: • Cyclopropylamine plasma polymers deposited on polycaprolactone nanofibers • Amine-rich films with high water stability

  10. Preparation of polymer microspheres by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Naka, Y.; Yamamoto, Y.; Yoshida, Y.; Tagawa, S.

    1995-01-01

    Cross-liking monomer, diethylene glycol dimethacrylate gives microspheres from organic solution by radiation-induced polymerization. /One of the remarkable result is that the number of the microspheres is not changing during the polymerization. Ethyl methacrylate, maleic anhydride, styrene and acrylamide are used as comonomers. These comonomers give the microspheres in the range of 0 to 0.4 as mol fractions. (author)

  11. Removal of DLC film on polymeric materials by low temperature atmospheric-pressure plasma jet

    Science.gov (United States)

    Kobayashi, Daichi; Tanaka, Fumiyuki; Kasai, Yoshiyuki; Sahara, Junki; Asai, Tomohiko; Hiratsuka, Masanori; Takatsu, Mikio; Koguchi, Haruhisa

    2017-10-01

    Diamond-like carbon (DLC) thin film has various excellent functions. For example, high hardness, abrasion resistance, biocompatibility, etc. Because of these functionalities, DLC has been applied in various fields. Removal method of DLC has also been developed for purpose of microfabrication, recycling the substrate and so on. Oxygen plasma etching and shot-blast are most common method to remove DLC. However, the residual carbon, high cost, and damage onto the substrate are problems to be solved for further application. In order to solve these problems, removal method using low temperature atmospheric pressure plasma jet has been developed in this work. The removal effect of this method has been demonstrated for DLC on the SUS304 substrate. The principle of this method is considered that oxygen radical generated by plasma oxidize carbon constituting the DLC film and then the film is removed. In this study, in order to widen application range of this method and to understand the mechanism of film removal, plasma irradiation experiment has been attempted on DLC on the substrate with low heat resistance. The DLC was removed successfully without any significant thermal damage on the surface of polymeric material.

  12. Metal doped fluorocarbon polymer films prepared by plasma polymerization using an RF planar magnetron target

    International Nuclear Information System (INIS)

    Biederman, H.; Holland, L.

    1983-01-01

    Fluorocarbon films have been prepared by plasma polymerization of CF 4 using an RF planar magnetron with an aluminium target. More than one order of magnitude higher deposition rate has been achieved in comparison with an r.f. diode system operated under similar conditions of monomer pressure and flow rate and power input. A glow discharge in a CF 4 [25%]-argon[75%] mixture was used to incorporate aluminium from a target electrode into the polymer films. The foregoing mixture and another based on CF 4 [87%]-argon[13%] were used in the RF discharge with a copper target. Some experiments with a gold target and pure CF 4 as the inlet gas were also made. The film structure was examined by SEM and TEM and characteristic micrographs are presented here. The composition of the films was estimated from an EAS study. The sheet resistivity of the metal/polymer film complexes was determined. (orig.)

  13. Metal doped polymer films prepared by simultaneous plasma polymerization of tetrafluoromethane and evaporation of gold

    Energy Technology Data Exchange (ETDEWEB)

    Martinu, L.; Biederman, H. (Karlova Univ., Prague (Czechoslovakia). Fakulta Matematicko-Fyzikalni); Zemek, J. (Ceskoslovenska Akademie Ved, Prague. Fyzikalni Ustav)

    The incorporation of gold from an evaporation source during plasma polymerization of tetrafluoromethane CF/sub 4/ in an RF (20 MHz) glow discharge excited by means of a planar magnetron has been investigated. Optical emission spectroscopy was used to monitor the deposition process in situ. The structure of the films was studied by transmission electron microscopy (TEM) observations. The sheet resistance and optical transmission measurements have been performed showing a dramatic influence of gold concentration on the film properties. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) analysis were used for determining the concentration depth profiles through the films. It has been shown that the presence of gold in the layers substantially reduces the fluorine content. The effect of various gold incorporation methods on the film characteristics has been discussed.

  14. Moisture resistant and anti-reflection optical coatings produced by plasma polymerization of organic compounds

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T.

    1975-01-01

    The need for protective coatings on critical optical surfaces, such as halide crystal windows or lenses used in spectroscopy, has long been recognized. It has been demonstrated that thin, one micron, organic coatings produced by polymerization of flourinated monomers in low temperature gas discharge (plasma) exhibit very high degrees of moisture resistence, e.g., hundreds of hours protection for cesium iodide vs. minutes before degradation sets in for untreated surfaces. The index of refraction of these coatings is intermediate between that of the halide substrate and air, a condition for anti-reflection, another desirable property of optical coatings. Thus, the organic coatings not only offer protection, but improved transmittance as well. The polymer coating is non-absorbing over the range 0.4 to 40 microns with an exception at 8.0 microns, the expected absorption for C-F bonds.

  15. Decreased Bacterial Attachment and Protein Adsorption to Coatings Produced by Low Enegy Plasma Polymerization

    DEFF Research Database (Denmark)

    Andersen, T.E.; Kingshott, Peter; Benter, M.

    .figure) .and E. coli grown on uncoated silicone compared to PP-PVP coated silicone (right figure). Results from the flow chamber analysis shows PP-PVP to be very good at preventing E. coli colonization during prolonged growth in flow chamber. At this point other surfaces and bacteria remains to be tested...... adsorption and bacteria attachment/colonization. This is emphasized by the fact that long dwelling urinary catheters, which is a typical silicone medical device, causes 5% per day incidence of urinary tract infection [1,2]. A demand therefore exists for surface modifications providing the silicone material......-coated crystals were then treated with one of the plasma polymerized coatings. Adsorption of fibrinogen, human serum albumin or immunoglobulin G was measured using a QCM-D instrument [5] (model E4, Q-Sense AB, Vastra Frolunda, Sweden) using a solution of 50llg/1 protein in PBS buffer. Results and Discussion: Our...

  16. Plasma Polymerized Thin Films of Maleic Anhydride and 1,2-methylenedioxybenzene for Improving Adhesion to Carbon Surfaces

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Goutianos, Stergios; Kingshott, Peter

    2007-01-01

    Low power 2-phase AC plasma polymerization has been used to surface modify glassy carbon substrates that are used as an experimental model for carbon fibers in reinforced composites. In order to probe the role of carboxylic acid density on the interfacial adhesion strength a combination...

  17. Plasma Polymerization of Acetylene onto silica: and Approach to control the distribution of silica in single elastomers and immiscible blends

    NARCIS (Netherlands)

    Tiwari, M.; Noordermeer, Jacobus W.M.; Ooij, W.J.; Dierkes, Wilma K.

    2008-01-01

    Surface modification of silica by acetylene plasma polymerization is applied in order to improve the dispersion in and compatibility with single rubbers and their blends. Silica, used as a reinforcing filler for elastomers, is coated with a polyacetylene (PA) film under vacuum conditions. Water

  18. Tribological behavior of plasma-polymerized aminopropyltriethoxysilane films deposited on thermoplastic elastomers substrates

    Energy Technology Data Exchange (ETDEWEB)

    Alba-Elías, Fernando, E-mail: fernando.alba@unirioja.es [Department of Mechanical Engineering, University of La Rioja, c/Luis de Ulloa 20, 26004 Logroño, La Rioja (Spain); Sainz-García, Elisa; González-Marcos, Ana [Department of Mechanical Engineering, University of La Rioja, c/Luis de Ulloa 20, 26004 Logroño, La Rioja (Spain); Ordieres-Meré, Joaquín [ETSII, Polytechnic University of Madrid, c/José Gutiérrez Abascal 2, 28006 Madrid (Spain)

    2013-07-01

    Thermoplastic elastomers (TPE) are multifunctional polymeric materials that are characterized by moderate cost, excellent mechanical properties (high elasticity, good flexibility, hardness, etc.), high tensile strength, oxidation and wettability. With an objective of reducing the superficial friction coefficient of TPE, this work analyzes the characteristics of coating films that are based on aminopropyltriethoxysilane (APTES) over a TPE substrate. Since this material is heat-sensitive, it is necessary to use a technology that permits the deposition of coatings at low temperatures without affecting the substrate integrity. Thus, an atmospheric-pressure plasma jet system (APPJ) with a dielectric barrier discharge (DBD) was used in this study. The coated samples were analyzed by Scanning Electron Microscopy, Atomic Force Microscopy, Fourier-Transform Infrared with Attenuated Total Reflectance Spectroscopy, X-ray Photoelectron Spectroscopy and tribological tests (friction coefficient and wear rate). The studies showed that the coated samples that contain a higher amount of forms of silicon (SiOSi) and nitrogen (amines, amides and imines) have lower friction coefficients. The sample coated at a specific plasma power of 550 W and an APTES flow rate of 1.5 slm had the highest values of SiOSi and nitrogen-containing groups peak intensity and atomic percentages of Si2p and SiO{sub 4}, and the lowest percentages of C1s and average friction coefficient. The results of this research permit one to conclude that APPJ with a DBD is a promising technique to use in coating SiO{sub x} and nitrogen-containing groups layers on polymeric materials. - Highlights: • SiO{sub x} thin films on thermoplastic elastomers by atmospheric pressure plasma jet. • Study of influence of plasma power and precursor flow rate on film's properties. • Friction coefficient is inversely related to the amount of SiOSi and N groups. • Nitrogen groups from the ionization gas (N{sub 2}) seem to

  19. Surface modification of biomaterials by pulsed laser ablation deposition and plasma/gamma polymerization

    Science.gov (United States)

    Rau, Kaustubh R.

    ablation was developed for the 248 nm laser irradiation of silicone. The model demonstrated a good fit to the experimental data and showed that silicone underwent ablation by a thermal mechanism. In addition to PLAD studies, functionalization of stainless steel was carried out by a combined plasma/gamma method involving deposition of a hexane plasma polymer by RF plasma polymerization, followed by gamma radiation graft polymerization of methacrylic acid. The hydrograft modified surfaces were further modified by chemisorption reactions with poly(ethylene imine) to produce amine-rich surfaces. Bovine serum albumin was then bound via amino groups using glutaraldehyde coupling. A streaming potential cell was also built and used to measure the zeta potential of these ionic surfaces.

  20. Deposition of stable amine coating onto polycaprolactone nanofibers by low pressure cyclopropylamine plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Manakhov, Anton [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Nečas, David [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Čechal, Jan [CEITEC — Central European Institute of Technology, Brno University of Technology, Technická 3058/10, 616 00 Brno (Czech Republic); Pavliňák, David [Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Eliáš, Marek [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); and others

    2015-04-30

    Amine-rich films are of high interest for the bio-applications including drug delivery and tissue engineering thanks to their high reactivity allowing the formation of the covalent linkages between biomolecules and a surface. However, the bio-applications of amine-rich films require their good stability in water which is often achieved at large expenses of the amine concentration. Recently, non-toxic cyclopropylamine (CPA) has been applied for the plasma polymerization of films bearing high NH{sub x} environment combined with the moderate thickness loss (20%) after water immersion for 48 h. In this work, the amine-rich film with the NH{sub x} concentration over 7 at.% was deposited on Si substrates and polycaprolactone nanofiber meshes by using CPA plasma polymerization (pulsed mode) in a vertically oriented stainless steel reactor. The substrates were placed at the radio frequency electrode and the ion bombardment caused by direct-current self-bias was suppressed by using high pressure of 50 Pa. Analysis of samples by scanning electron microscopy did not reveal any cracks in the deposited layer formed during a sample immersion in water. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed a slight oxidation of amine groups in water but the film still contained 5 at.% of NH{sub x} (according to the N1s XPS fitting) after the immersion. The rapid oxidation of amine groups was observed during the aging experiment carried out in air at room temperature because FTIR revealed an increase of amide peaks that increased progressively with aging time. However, this oxidation was significantly reduced if the plasma polymer was stored at − 20 °C. Since the films exhibit high amine concentration and very good water stability they have great potential for applications as biocompatible functional coatings. - Highlights: • Cyclopropylamine plasma polymers deposited on polycaprolactone nanofibers • Amine-rich films with high

  1. Polymerization by plasma of trichloroethylene by means of resistive and inductive coupling; Polimerizacion por plasmas de tricloroetileno por medio de acoplamiento resistivo e inductivo

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, M.; Cruz, G.; Olayo, M.G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Timoshina, T. [IPN, ESIQIE, 07738 Mexico D.F. (Mexico); Morales, J.; Olayo, R. [UAM-I, 09340 Mexico D.F. (Mexico)

    2004-07-01

    It was carried out the polymerization for plasma of the trichloroethylene by means of two types of coupling, resistive and inductive with the objective of studying the structure, morphology and the electric properties of the polymers obtained under these conditions. The structure and morphology of the polymers were studied by means of EDS and FT-IR spectroscopies. (Author)

  2. Pulsed Plasma Polymerization of Perfluorooctyl Ethylene for Transparent Hydrophobic Thin Coatings

    International Nuclear Information System (INIS)

    Liu Xiaojun; Wang Lei; Hao Jie; Chu Liqiang

    2015-01-01

    Herein we report on the deposition of transparent hydrophobic thin coatings by radio frequency plasma polymerization (PP) of perfluorooctyl ethylene (PFOE) in both pulsed and continuous wave (CW) modes. The chemical compositions of the resulting PP-PFOE coatings were confirmed by means of Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The thicknesses and surface morphologies of the coatings were examined using surface plasmon resonance spectroscopy and atomic force microscopy. The surface wetting properties and optical transmittance were measured using a water contact angle goniometer and UV-vis spectroscopy. The FT-IR and XPS data showed that the PP-PFOE coatings deposited in the pulsed mode had a higher retention of CF 2 groups compared to those from the CW mode. While the water contact angle of the freshly deposited PP-PFOE from the pulsed mode showed a decrease from 120 degrees to 111 degrees in the first two days, it then remained almost unchanged up to 45 days. The UV-vis data indicated that a PP-PFOE coating 30.6 nm thick had a light transmittance above 90% in the UV and visible ranges. The deposition rates under various plasma conditions are also discussed. (paper)

  3. Characterization of Plasma-Polymerized Fused Polycyclic Compounds for Binding Conducting Polymers

    DEFF Research Database (Denmark)

    Winther-Jensen, Bjørn; Norrman, Kion; Kingshott, Peter

    2005-01-01

    with hydrogen in the position which is able to co-polymerize with thiophene derivatives polymerized by conventional oxidative polymerization, thereby forming a conducting thiophene polymer bonded to the substrate. The durability of the surface modification procedure is demonstrated by micropatterning of PEDT...

  4. Atmospheric Pressure Plasma Polymerization Synthesis and Characterization of Polyaniline Films Doped with and without Iodine

    Directory of Open Access Journals (Sweden)

    Choon-Sang Park

    2017-11-01

    Full Text Available Although polymerized aniline (polyaniline, PANI with and without iodine (I2 doping has already been extensively studied, little work has been done on the synthesis of PANI films using atmospheric pressure plasma (APP deposition. Therefore, this study characterized pure and I2-doped PANI films synthesized using an advanced APP polymerization system. The I2 doping was conducted ex-situ and using an I2 chamber method following the APP deposition. The pure and I2-doped PANI films were structurally analyzed using field emission scanning electron microscope (FE-SEM, atomic force microscope (AFM, X-ray Diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, X-ray photoelectron spectroscopy (XPS, and time of flight secondary ion mass spectrometry (ToF-SIMS studies. When increasing the I2 doping time, the plane and cross-sectional SEM images showed a decrease in the width and thickness of the PANI nanofibers, while the AFM results showed an increase in the roughness and grain size of the PANI films. Moreover, the FT-IR, XPS, and ToF-SIMS results showed an increase in the content of oxygen-containing functional groups and C=C double bonds, yet decrease in the C–N and C–H bonds when increasing the I2 doping time due to the reduction of hydrogen in the PANI films via the I2. To check the suitability of the conductive layer for polymer display applications, the resistance variations of the PANI films grown on the interdigitated electrode substrates were also examined according to the I2 doping time.

  5. Metal doped fluorocarbon polymer films prepared by plasma polymerization using an RF planar magnetron target

    Energy Technology Data Exchange (ETDEWEB)

    Biederman, H.; Holland, L. (Sussex Univ., Brighton (UK). Lab. for Plasma Materials Processing)

    1983-07-01

    Fluorocarbon films have been prepared by plasma polymerization of CF/sub 4/ using an RF planar magnetron with an aluminium target. More than one order of magnitude higher deposition rate has been achieved in comparison with an R.F. diode system operated under similar conditions of monomer pressure and flow rate and power input. A glow discharge in a CF/sub 4/(25%)-argon(75%) mixture was used to incorporate aluminium from a target electrode into the polymer films. The foregoing mixture and another based on CF/sub 4/(87%)-argon(13%) were used in the RF discharge with a copper target. Some experiments with a gold target and pure CF/sub 4/ as the inlet gas were also made. The film structure was examined by SEM and TEM and characteristic micrographs are presented here. The composition of the films was estimated from an EAS study. The sheet resistivity of the metal/polymer film complexes was determined.

  6. Plasma-polymerized films providing selective affinity to the polarity of vaporized organic solvents

    International Nuclear Information System (INIS)

    Akimoto, Takuo; Ikeshita, Yusuke; Terashima, Ryo; Karube, Isao

    2009-01-01

    Plasma-polymerized films (PPFs) were fabricated as recognition membranes for a vapor-sensing device, and their affinity to vaporized organic solvents was evaluated with surface plasmon resonance. The affinity we intended to create is the selective sorption of the vaporized organic solvents depending on their polarity. For this purpose, acetonitrile, ethylenediamine (EDA), styrene, hexamethyldisiloxane (HMDSO), and hexamethyldisilazane were used to fabricate PPFs. Vaporized methanol, ethanol, and 1-propanol were used as high-polar solvents to be analyzed. Hexane, toluene, and p-xylene were used as low-polar solvents. As a result, the HMDSO-PPF with 97.3 o of contact angle was found to provide affinity to the low-polar solvents. In contrast, the EDA-PPF with 7.1 o of contact angle provided affinity to the high-polar solvents. Observations of the surface morphology of the HMDSO- and EDA-PPFs with a scanning electron microscope revealed that they are composed of nano-scale islands.

  7. Decreased material-activation of the complement system using low-energy plasma polymerized poly(vinyl pyrrolidone) coatings

    DEFF Research Database (Denmark)

    Andersen, T.E.; Kolmos, H.J.; Palarasah, Yaseelan

    2011-01-01

    In the current study we investigate the activation of blood complement on medical device silicone rubber and present a plasma polymerized vinyl pyrrolidone (ppVP) coating which strongly decreases surface-activation of the blood complement system. We show that uncoated silicone and polystyrene...... surface. The ppVP surface is furthermore characterized physically and chemically using scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR), which indicates preservation of chemical functionality by the applied plasma process. Overall, the pp...

  8. Large enhanced dielectric permittivity in polyaniline passivated core-shell nano magnetic iron oxide by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Joy, Lija K.; Sooraj, V.; Sethulakshmi, N.; Anantharaman, M. R., E-mail: mraiyer@yahoo.com [Department of Physics, Cochin University of Science and Technology, Cochin-682022, Kerala (India); Sajeev, U. S. [Department of Physics, Government College, Kottayam-686613, Kerala (India); Nair, Swapna S. [Department of Physics, School of Mathematical and Physical Sciences, Central University of Kerala, Kasargode-671123, Kerala (India); Narayanan, T. N. [CSIR-Central Electrochemical Research Institute, Karaikkudi-630006, Tamil Nadu (India); Ajayan, P. M. [Department of Material Science and Nano Engineering, Rice University, 6100 Main Street, Houston, Texas 7700 (United States)

    2014-03-24

    Commercial samples of Magnetite with size ranging from 25–30 nm were coated with polyaniline by using radio frequency plasma polymerization to achieve a core shell structure of magnetic nanoparticle (core)–Polyaniline (shell). High resolution transmission electron microscopy images confirm the core shell architecture of polyaniline coated iron oxide. The dielectric properties of the material were studied before and after plasma treatment. The polymer coated magnetite particles exhibited a large dielectric permittivity with respect to uncoated samples. The dielectric behavior was modeled using a Maxwell–Wagner capacitor model. A plausible mechanism for the enhancement of dielectric permittivity is proposed.

  9. Plasma-polymerized SiOx deposition on polymer film surfaces for preparation of oxygen gas barrier polymeric films

    International Nuclear Information System (INIS)

    Inagaki, N.

    2003-01-01

    SiOx films were deposited on surfaces of three polymeric films, PET, PP, and Nylon; and their oxygen gas barrier properties were evaluated. To mitigate discrepancies between the deposited SiOx and polymer film, surface modification of polymer films was done, and how the surface modification could contribute to was discussed from the viewpoint of apparent activation energy for the permeation process. The SiOx deposition on the polymer film surfaces led to a large decrease in the oxygen permeation rate. Modification of polymer film surfaces by mans of the TMOS or Si-COOH coupling treatment in prior to the SiOx deposition was effective in decreasing the oxygen permeation rate. The cavity model is proposed as an oxygen permeation process through the SiOx-deposited Nylon film. From the proposed model, controlling the interface between the deposited SiOx film and the polymer film is emphasized to be a key factor to prepare SiOx-deposited polymer films with good oxygen gas barrier properties. (author)

  10. Polyethylene Oxide Films Polymerized by Radio Frequency Plasma-Enhanced Chemical Vapour Phase Deposition and Its Adsorption Behaviour of Platelet-Rich Plasma

    International Nuclear Information System (INIS)

    Wen-Juan, Hu; Fen-Yan, Xie; Qiang, Chen; Jing, Weng

    2008-01-01

    We present polyethylene oxide (PEO) functional films polymerized by rf plasma-enhanced vapour chemical deposition (rf-PECVD) on p-Si (100) surface with precursor ethylene glycol dimethyl ether (EGDME) and diluted Ar in pulsed plasma mode. The influences of discharge parameters on the film properties and compounds are investigated. The film structure is analysed by Fourier transform infrared (FTIR) spectroscopy. The water contact angle measurement and atomic force microscope (AFM) are employed to examine the surface polarity and to detect surface morphology, respectively. It is concluded that the smaller duty cycle in pulsed plasma mode contributes to the rich C-O-C (EO) group on the surfaces. As an application, the adsorption behaviour of platelet-rich plasma on plasma polymerization films performed in-vitro is explored. The shapes of attached cells are studied in detail by an optic invert microscope, which clarifies that high-density C-O-C groups on surfaces are responsible for non-fouling adsorption behaviour of the PEO films

  11. Polyethylene Oxide Films Polymerized by Radio Frequency Plasma-Enhanced Chemical Vapour Phase Deposition and Its Adsorption Behaviour of Platelet-Rich Plasma

    Science.gov (United States)

    Hu, Wen-Juan; Xie, Fen-Yan; Chen, Qiang; Weng, Jing

    2008-10-01

    We present polyethylene oxide (PEO) functional films polymerized by rf plasma-enhanced vapour chemical deposition (rf-PECVD) on p-Si (100) surface with precursor ethylene glycol dimethyl ether (EGDME) and diluted Ar in pulsed plasma mode. The influences of discharge parameters on the film properties and compounds are investigated. The film structure is analysed by Fourier transform infrared (FTIR) spectroscopy. The water contact angle measurement and atomic force microscope (AFM) are employed to examine the surface polarity and to detect surface morphology, respectively. It is concluded that the smaller duty cycle in pulsed plasma mode contributes to the rich C-O-C (EO) group on the surfaces. As an application, the adsorption behaviour of platelet-rich plasma on plasma polymerization films performed in-vitro is explored. The shapes of attached cells are studied in detail by an optic invert microscope, which clarifies that high-density C-O-C groups on surfaces are responsible for non-fouling adsorption behaviour of the PEO films.

  12. Hydrophobic thiol-ene surfaces fabricated via plasma activation and photo polymerization

    Science.gov (United States)

    Champathet, P.; Ervithayasuporn, V.; Osotchan, T.; Dangtip, S.

    2017-09-01

    Alumina, such as glazed alumina for electrical insulator, operated in an open field subjects to a very harsh condition; resulting in lifetime shortening. Coating hydrophobic layer on alumina surface can help prolonging its lifetime. In this study, 25 ×25 mm alumina sheets were used as substrates. The hydrophobic composite polymers were prepared from (3-mercaptopropyl)trimethoxysilane(MPTMS), 2,4,6,8-tetramethyl-2,4,6,8tetravinylcyclotetra siloxane(TMTVSi), pentaerythritoltetra(3-mercaptopropionate)(PETMP), 2,2-dimethoxy-2-phe nylaceto phenone(photoinitiator) and heptadecafluorodecylmethacrylate(HEFDMA) via the thiol-ene reaction. The alumina sheets were first activated by dielectric-barrier discharge plasma to improve its adhesion. All the polymers were found to optimize at the ratio of (MPTMS:TMTVSi:PETMP:HDFDMA) to 4:2:1:2 for coating on the alumina substrate. To enhance polymerization, 2,2-dimethoxy-2-phenylaceto phenome was also used as a photoinitiator A proper mixing sequence in the thiol-ene reaction results in film with excellent surface retention after prolong soaking in solvent such as acetone. FTIR shows that S-H and C=C functional groups have significantly changed after photopolymerization and thermally cured. The static contact angle increase from mere 53.0°±1.5° of the uncoated substrate to 120.0°±1.2° after coating. SEM shows the film with clear appearance of a few-micron thick. Under AFM, the coated surface roughness was about 9.3 nm with evenly distributed spikes of a few nanometer in height. The cross-cut test also confirmed the film was very smooth and none of the square of the films detached.

  13. Influence of the radio-frequency power on the physical and optical properties of plasma polymerized cyclohexane thin films

    Energy Technology Data Exchange (ETDEWEB)

    Manaa, C., E-mail: chadlia.el.manaa@gmail.com [Laboratoire de Physique de la Matière Condensée, Université de Picardie Jules Verne, UFR des Sciences d' Amiens, 33 rue Saint Leu, 80039 Amiens CEDEX 2 (France); Laboratoire des Matériaux Avancés et Phénomènes Quantiques, Université de Tunis El-Manar, Faculté des Sciences de Tunis, Campus universitaire El-Manar, 1068 Tunis (Tunisia); Lejeune, M. [Laboratoire de Physique de la Matière Condensée, Université de Picardie Jules Verne, UFR des Sciences d' Amiens, 33 rue Saint Leu, 80039 Amiens CEDEX 2 (France); Kouki, F. [Laboratoire des Matériaux Avancés et Phénomènes Quantiques, Université de Tunis El-Manar, Faculté des Sciences de Tunis, Campus universitaire El-Manar, 1068 Tunis (Tunisia); Durand-Drouhin, O. [Laboratoire de Physique de la Matière Condensée, Université de Picardie Jules Verne, UFR des Sciences d' Amiens, 33 rue Saint Leu, 80039 Amiens CEDEX 2 (France); Bouchriha, H. [Laboratoire des Matériaux Avancés et Phénomènes Quantiques, Université de Tunis El-Manar, Faculté des Sciences de Tunis, Campus universitaire El-Manar, 1068 Tunis (Tunisia); and others

    2014-06-02

    We investigate in the present study the effects of the radio-frequency plasma power on the opto-electronical properties of the polymeric amorphous hydrogenated carbon thin films deposited at room temperature and different radio-frequency powers by plasma-enhanced chemical vapor deposition method using cyclohexane as precursor. A combination of U.V.–Visible and infrared transmission measurements is applied to characterize the bonding and electronic properties of these films. Some film properties namely surface roughness, contact angle, surface energy, and optical properties are found to be significantly influenced by the radio-frequency power. The changes in these properties are analyzed within the microstructural modifications occurring during growth. - Highlights: • Effects of the radio-frequency power on the optoelectronic properties of thin films • Elaboration of plasma polymerized thin films using cyclohexane as precursor gas • The use of U.V.–Visible-infrared transmission, and optical gap • Study of the surface topography of the films by using Atomic Force microscopy • The use of a capacitively coupled plasma enhanced chemical vapor deposition method.

  14. Influence of the radio-frequency power on the physical and optical properties of plasma polymerized cyclohexane thin films

    International Nuclear Information System (INIS)

    Manaa, C.; Lejeune, M.; Kouki, F.; Durand-Drouhin, O.; Bouchriha, H.

    2014-01-01

    We investigate in the present study the effects of the radio-frequency plasma power on the opto-electronical properties of the polymeric amorphous hydrogenated carbon thin films deposited at room temperature and different radio-frequency powers by plasma-enhanced chemical vapor deposition method using cyclohexane as precursor. A combination of U.V.–Visible and infrared transmission measurements is applied to characterize the bonding and electronic properties of these films. Some film properties namely surface roughness, contact angle, surface energy, and optical properties are found to be significantly influenced by the radio-frequency power. The changes in these properties are analyzed within the microstructural modifications occurring during growth. - Highlights: • Effects of the radio-frequency power on the optoelectronic properties of thin films • Elaboration of plasma polymerized thin films using cyclohexane as precursor gas • The use of U.V.–Visible-infrared transmission, and optical gap • Study of the surface topography of the films by using Atomic Force microscopy • The use of a capacitively coupled plasma enhanced chemical vapor deposition method

  15. Bacterial adhesion on conventional and self-ligating metallic brackets after surface treatment with plasma-polymerized hexamethyldisiloxane

    Directory of Open Access Journals (Sweden)

    Rogerio Amaral Tupinambá

    Full Text Available ABSTRACT Introduction: Plasma-polymerized film deposition was created to modify metallic orthodontic brackets surface properties in order to inhibit bacterial adhesion. Methods: Hexamethyldisiloxane (HMDSO polymer films were deposited on conventional (n = 10 and self-ligating (n = 10 stainless steel orthodontic brackets using the Plasma-Enhanced Chemical Vapor Deposition (PECVD radio frequency technique. The samples were divided into two groups according to the kind of bracket and two subgroups after surface treatment. Scanning Electron Microscopy (SEM analysis was performed to assess the presence of bacterial adhesion over samples surfaces (slot and wings region and film layer integrity. Surface roughness was assessed by Confocal Interferometry (CI and surface wettability, by goniometry. For bacterial adhesion analysis, samples were exposed for 72 hours to a Streptococcus mutans solution for biofilm formation. The values obtained for surface roughness were analyzed using the Mann-Whitney test while biofilm adhesion were assessed by Kruskal-Wallis and SNK test. Results: Significant statistical differences (p 0.05. Conclusion: Plasma-polymerized film deposition was only effective on reducing surface roughness and bacterial adhesion in conventional brackets. It was also noted that conventional brackets showed lower biofilm adhesion than self-ligating brackets despite the absence of film.

  16. Bacterial adhesion on conventional and self-ligating metallic brackets after surface treatment with plasma-polymerized hexamethyldisiloxane

    Science.gov (United States)

    Tupinambá, Rogerio Amaral; Claro, Cristiane Aparecida de Assis; Pereira, Cristiane Aparecida; Nobrega, Celestino José Prudente; Claro, Ana Paula Rosifini Alves

    2017-01-01

    ABSTRACT Introduction: Plasma-polymerized film deposition was created to modify metallic orthodontic brackets surface properties in order to inhibit bacterial adhesion. Methods: Hexamethyldisiloxane (HMDSO) polymer films were deposited on conventional (n = 10) and self-ligating (n = 10) stainless steel orthodontic brackets using the Plasma-Enhanced Chemical Vapor Deposition (PECVD) radio frequency technique. The samples were divided into two groups according to the kind of bracket and two subgroups after surface treatment. Scanning Electron Microscopy (SEM) analysis was performed to assess the presence of bacterial adhesion over samples surfaces (slot and wings region) and film layer integrity. Surface roughness was assessed by Confocal Interferometry (CI) and surface wettability, by goniometry. For bacterial adhesion analysis, samples were exposed for 72 hours to a Streptococcus mutans solution for biofilm formation. The values obtained for surface roughness were analyzed using the Mann-Whitney test while biofilm adhesion were assessed by Kruskal-Wallis and SNK test. Results: Significant statistical differences (p 0.05). Conclusion: Plasma-polymerized film deposition was only effective on reducing surface roughness and bacterial adhesion in conventional brackets. It was also noted that conventional brackets showed lower biofilm adhesion than self-ligating brackets despite the absence of film. PMID:28902253

  17. Bacterial adhesion on conventional and self-ligating metallic brackets after surface treatment with plasma-polymerized hexamethyldisiloxane.

    Science.gov (United States)

    Tupinambá, Rogerio Amaral; Claro, Cristiane Aparecida de Assis; Pereira, Cristiane Aparecida; Nobrega, Celestino José Prudente; Claro, Ana Paula Rosifini Alves

    2017-01-01

    Plasma-polymerized film deposition was created to modify metallic orthodontic brackets surface properties in order to inhibit bacterial adhesion. Hexamethyldisiloxane (HMDSO) polymer films were deposited on conventional (n = 10) and self-ligating (n = 10) stainless steel orthodontic brackets using the Plasma-Enhanced Chemical Vapor Deposition (PECVD) radio frequency technique. The samples were divided into two groups according to the kind of bracket and two subgroups after surface treatment. Scanning Electron Microscopy (SEM) analysis was performed to assess the presence of bacterial adhesion over samples surfaces (slot and wings region) and film layer integrity. Surface roughness was assessed by Confocal Interferometry (CI) and surface wettability, by goniometry. For bacterial adhesion analysis, samples were exposed for 72 hours to a Streptococcus mutans solution for biofilm formation. The values obtained for surface roughness were analyzed using the Mann-Whitney test while biofilm adhesion were assessed by Kruskal-Wallis and SNK test. Significant statistical differences (pbrackets after surface treatment and between conventional and self-ligating brackets; no significant statistical differences were observed between self-ligating groups (p> 0.05). Plasma-polymerized film deposition was only effective on reducing surface roughness and bacterial adhesion in conventional brackets. It was also noted that conventional brackets showed lower biofilm adhesion than self-ligating brackets despite the absence of film.

  18. About a possibility of increasing the adhesion strength between mineral glass and polymeric binder under radio-frequency induction plasma treatment

    International Nuclear Information System (INIS)

    Miftakhov, I S; Trofimov, A V; Nagmutdinova, A I; Voznesensky, E F; Sharifullin, F S; Krasina, I V; Rakhmatullina, G R

    2017-01-01

    The paper investigated influences of radio-frequency induction plasma treatment on the surface of sheet mineral glasses for household purpose. Discussion for casting the most suitable treatment modes and theirs substantiation is shown. During the investigation the most productive plasma treatment modes for applied binders have been found. It is shown that the durability of adhesive joints between mineral glass and polymeric binder under low-temperature plasma treatment increase to 65%. (paper)

  19. Crumb waste tire rubber surface modification by plasma polymerization of ethanol and its application on oil-well cement

    Energy Technology Data Exchange (ETDEWEB)

    Xiaowei, Cheng [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu (China); School of Material Science and Engineering, Southwest Petroleum University, Chengdu (China); Sheng, Huang [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu (China); School of Oil and Natural Gas Engineering, Southwest Petroleum University, Chengdu (China); Xiaoyang, Guo, E-mail: guoxiaoyangswpi@126.com [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu (China); School of Oil and Natural Gas Engineering, Southwest Petroleum University, Chengdu (China); Wenhui, Duan, E-mail: wenhui.duan@monash.edu [Department of Civil Engineering, Monash University, Clayton, Melbourne 3800 (Australia)

    2017-07-01

    Highlights: • The crumb waste tire rubber (WTR) was modified by plasma polymerization of ethanol. • Hydrophilic groups were introduced onto WTR surface and improved its hydrophilia. • The functionalized crumb WTR was applied in oil-well cement. • The mechanical properties of modified oil-well cement were intensively enhanced. - Abstract: Crumb waste tire rubber (WTR) was pretreated by oxygen low temperature plasma (LTP) and modified by LTP polymerization process of ethanol monomer to improve the adhesion property with oil-well cement matrix and the mechanical properties of cement. The surface properties of modified crumb WTR and the mechanical properties and structures of modified oil-well cement were investigated by means of contact angle measurement, dispersion test, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), mechanics performance tests, permeability test and scanning electron microscopy (SEM). It was demonstrated that LTP treatment changed both the surface composition and roughness. The contact angle of pretreated crumb WTR dramatically fell from 122° to 34°, and sample with ethanol LPT polymer film decreased even further to 11°. The ATR-FTIR and XPS analysis results demonstrated that hydrophilic groups, such as –COOH, C–OH, and –CHO, were introduced on the WTR surface. The oxygen atomic percent increased from 8.11% to 14.50% and 24.83%. The mechanical properties, porosity and permeability of raw cement were compared to samples modified by untreated crumb WTR, pretreated crumb WTR and ethanol LTP polymerization treated crumb WTR. It was found that after 28 days, the compressive strength of the samples with the untreated crumb WTR decreased to 80% with respect to raw cement. The tensile strength and flexural strength also had a slight reduction compared with the raw cement. On the contrary, after 28 days, the tensile strength of cement modified by LTP polymerization

  20. Crumb waste tire rubber surface modification by plasma polymerization of ethanol and its application on oil-well cement

    International Nuclear Information System (INIS)

    Xiaowei, Cheng; Sheng, Huang; Xiaoyang, Guo; Wenhui, Duan

    2017-01-01

    Highlights: • The crumb waste tire rubber (WTR) was modified by plasma polymerization of ethanol. • Hydrophilic groups were introduced onto WTR surface and improved its hydrophilia. • The functionalized crumb WTR was applied in oil-well cement. • The mechanical properties of modified oil-well cement were intensively enhanced. - Abstract: Crumb waste tire rubber (WTR) was pretreated by oxygen low temperature plasma (LTP) and modified by LTP polymerization process of ethanol monomer to improve the adhesion property with oil-well cement matrix and the mechanical properties of cement. The surface properties of modified crumb WTR and the mechanical properties and structures of modified oil-well cement were investigated by means of contact angle measurement, dispersion test, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), mechanics performance tests, permeability test and scanning electron microscopy (SEM). It was demonstrated that LTP treatment changed both the surface composition and roughness. The contact angle of pretreated crumb WTR dramatically fell from 122° to 34°, and sample with ethanol LPT polymer film decreased even further to 11°. The ATR-FTIR and XPS analysis results demonstrated that hydrophilic groups, such as –COOH, C–OH, and –CHO, were introduced on the WTR surface. The oxygen atomic percent increased from 8.11% to 14.50% and 24.83%. The mechanical properties, porosity and permeability of raw cement were compared to samples modified by untreated crumb WTR, pretreated crumb WTR and ethanol LTP polymerization treated crumb WTR. It was found that after 28 days, the compressive strength of the samples with the untreated crumb WTR decreased to 80% with respect to raw cement. The tensile strength and flexural strength also had a slight reduction compared with the raw cement. On the contrary, after 28 days, the tensile strength of cement modified by LTP polymerization

  1. Crumb waste tire rubber surface modification by plasma polymerization of ethanol and its application on oil-well cement

    Science.gov (United States)

    Xiaowei, Cheng; Sheng, Huang; Xiaoyang, Guo; Wenhui, Duan

    2017-07-01

    Crumb waste tire rubber (WTR) was pretreated by oxygen low temperature plasma (LTP) and modified by LTP polymerization process of ethanol monomer to improve the adhesion property with oil-well cement matrix and the mechanical properties of cement. The surface properties of modified crumb WTR and the mechanical properties and structures of modified oil-well cement were investigated by means of contact angle measurement, dispersion test, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), mechanics performance tests, permeability test and scanning electron microscopy (SEM). It was demonstrated that LTP treatment changed both the surface composition and roughness. The contact angle of pretreated crumb WTR dramatically fell from 122° to 34°, and sample with ethanol LPT polymer film decreased even further to 11°. The ATR-FTIR and XPS analysis results demonstrated that hydrophilic groups, such as -COOH, C-OH, and -CHO, were introduced on the WTR surface. The oxygen atomic percent increased from 8.11% to 14.50% and 24.83%. The mechanical properties, porosity and permeability of raw cement were compared to samples modified by untreated crumb WTR, pretreated crumb WTR and ethanol LTP polymerization treated crumb WTR. It was found that after 28 days, the compressive strength of the samples with the untreated crumb WTR decreased to 80% with respect to raw cement. The tensile strength and flexural strength also had a slight reduction compared with the raw cement. On the contrary, after 28 days, the tensile strength of cement modified by LTP polymerization treated WTR increased 11.03% and 13.36%, and the flexural strength increased 9.65% and 7.31%, respectively. A decrease in the compressive strength also occurred but was inconspicuous. A tight interface bonding for ethanol LTP polymerization treated WTR with cement matrix was observed via an SEM image.

  2. Surface Modification of Sodium Montmorillonite Nanoclay by Plasma Polymerization and Its Effect on the Properties of Polystyrene Nanocomposites

    Directory of Open Access Journals (Sweden)

    Rosa Idalia Narro-Céspedes

    2018-01-01

    Full Text Available Sodium montmorillonite nanoclay (Na+-MMT was modified by plasma polymerization with methyl methacrylate (MMA and styrene (St as monomers and was denominated as Na+-MMT/MMA and Na+-MMT/St, respectively. This plasma modified nanoclay was used as reinforcement for polystyrene (PS nanocomposites that were prepared by melt mixing. Pristine and modified Na+-MMT nanoclay were analyzed by the dispersion in various solvents, Fourier transform infrared spectroscopy (FTIR, thermogravimetric analysis (TGA, and scanning electron microscopy (SEM. The results confirmed a change in hydrophilicity of the modified Na+-MMT, as well as the presence of a polymeric material over its surface. The pristine PS/Na+-MMT and modified PS/Na+-MMT/MMA and PS/Na+-MMT/St nanocomposites were studied with X-ray diffraction (XRD, differential scanning calorimetry (DSC, and TGA, as well as mechanical properties. It was found that the PS/Na+-MMT/St nanocomposites presented better thermal properties and an improvement in Young’s modulus (YM in compared to PS/Na+-MMT/MMA nanocomposites.

  3. Wetting, Solubility and Chemical Characteristics of Plasma-Polymerized 1-Isopropyl-4-Methyl-1,4-Cyclohexadiene Thin Films

    Directory of Open Access Journals (Sweden)

    Jakaria Ahmad

    2014-07-01

    Full Text Available Investigations on the wetting, solubility and chemical composition of plasma polymer thin films provide an insight into the feasibility of implementing these polymeric materials in organic electronics, particularly where wet solution processing is involved. In this study, thin films were prepared from 1-isopropyl-4-methyl-1,4-cyclohexadiene (γ-Terpinene using radio frequency (RF plasma polymerization. FTIR showed the polymers to be structurally dissimilar to the original monomer and highly cross-linked, where the loss of original functional groups and the degree of cross-linking increased with deposition power. The polymer surfaces were hydrocarbon-rich, with oxygen present in the form of O–H and C=O functional groups. The oxygen content decreased with deposition power, with films becoming more hydrophobic and, thus, less wettable. The advancing and receding contact angles were investigated, and the water advancing contact angle was found to increase from 63.14° to 73.53° for thin films prepared with an RF power of 10 W to 75 W. The wetting envelopes for the surfaces were constructed to enable the prediction of the surfaces’ wettability for other solvents. The effect of roughness on the wetting behaviour of the films was insignificant. The polymers were determined to resist solubilization in solvents commonly used in the deposition of organic semiconducting layers, including chloroform and chlorobenzene, with higher stability observed in films fabricated at higher RF power.

  4. Surface modification of blood-contacting biomaterials by plasma-polymerized superhydrophobic films using hexamethyldisiloxane and tetrafluoromethane as precursors

    Energy Technology Data Exchange (ETDEWEB)

    Hsiao, Chaio-Ru [Department of Materials Science and Engineering, Feng Chia University, No. 100, Wenhwa Rd., Seatwen District, Taichung City 40724, Taiwan (China); Lin, Cheng-Wei [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, No. 666, Buzih Rd., Beitun District, Taichung City 40601, Taiwan (China); Chou, Chia-Man, E-mail: cmchou@vghtc.gov.tw [Department of Surgery, Taichung Veterans General Hospital, No. 1650, Sec. 4, Taiwan Boulevard, Seatwen District, Taichung City 40705, Taiwan (China); Department of Medicine, National Yang-Ming University, No. 155, Sec. 2, Linong Street, Beitou District, Taipei City 11221, Taiwan (China); Chung, Chi-Jen, E-mail: cjchung@seed.net.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, No. 666, Buzih Rd., Beitun District, Taichung City 40601, Taiwan (China); He, Ju-Liang [Department of Materials Science and Engineering, Feng Chia University, No. 100, Wenhwa Rd., Seatwen District, Taichung City 40724, Taiwan (China)

    2015-08-15

    Highlights: • Biomaterials modified by nanoparticle-containing plasma polymerized films. • A superhydrophoic film was obtained, and the properties of the coating were examined. • In vitro blood compatibility tests revealed neither platelet adhesion nor fibrinogen adsorption. • Surface modification technology of medical devices: non-cytotoxic and no blood clot formation. - Abstract: This paper proposes a plasma polymerization system that can be used to modify the surface of the widely used biomaterial, polyurethane (PU), by employing low-cost hexamethyldisiloxane (HMDSO) and tetrafluoromethane (CF{sub 4}) as precursors; this system features a pulsed-dc power supply. Plasma-polymerized HMDSO/CF{sub 4} (pp-HC) with coexisting micro- and nanoscale morphology was obtained as a superhydrophobic coating material by controlling the HMDSO/CF{sub 4} (f{sub H}) monomer flow ratio. The developed surface modification technology can be applied to medical devices, because it is non-cytotoxic and has favorable hemocompatibility, and no blood clots form when the device surface direct contacts. Experimental results reveal that the obtained pp-HC films contained SiO{sub x} nanoparticles randomly dispersed on the micron-scale three-dimensional network film surface. The −CF functional group, −CF{sub 2} bonding, and SiO{sub x} were detected on the film surface. The maximal water contact angle of the pp-HC coating was 161.2°, apparently attributable to the synergistic effect of the coexisting micro- and nanoscale surface morphology featuring a low surface-energy layer. The superhydrophobic and antifouling characteristics of the coating were retained even after it was rubbed 20 times with a steel wool tester. Results of in vitro cytotoxicity, fibrinogen adsorption, and platelet adhesion tests revealed favorable myoblast cell proliferation and the virtual absence of fibrinogen adsorption and platelet adhesion on the pp-HC coated specimens. These quantitative findings imply

  5. Atmospheric pressure plasma processing of polymeric materials utilizing close proximity indirect exposure

    Science.gov (United States)

    Paulauskas, Felix L.; Bonds, Truman

    2016-09-20

    A plasma treatment method that includes providing treatment chamber including an intermediate heating volume and an interior treatment volume. The interior treatment volume contains an electrode assembly for generating a plasma and the intermediate heating volume heats the interior treatment volume. A work piece is traversed through the treatment chamber. A process gas is introduced to the interior treatment volume of the treatment chamber. A plasma is formed with the electrode assembly from the process gas, wherein a reactive species of the plasma is accelerated towards the fiber tow by flow vortices produced in the interior treatment volume by the electrode assembly.

  6. Evidence of coexistence of micro and nanoporosity of organo-silica polymeric films deposited on silicon by plasma deposition

    International Nuclear Information System (INIS)

    Purohit, Viswas; Mielczarski, Ela; Mielczarski, Jerzy A.; Akesso, Laurent

    2013-01-01

    A range of hybrid, SiOCH films were deposited on silicon substrates within a radio frequency plasma reactor using hexamethyldisiloxane (HMDSO) as a precursor. The plasma polymerized films were deposited at various HMDSO/argon/oxygen ratios. The composition and structure, at microscopic and nanoscopic levels, of the deposited films were determined by external reflection and transmission Fourier Transform Infrared (FTIR) spectroscopy as well as by X-Ray Photoelectron Spectroscopy (XPS). The content of carbon and oxygen in films were found to be inversely proportional to each other. XPS results showed that the outermost surface of the deposited films are nanoporous and coexist with microporosity which was revealed by electron microscopy. The structure of deposited coatings is anisotropic as was documented by polarized external reflection FTIR spectroscopy. Several correlations between the film chemical composition, surface structure, and macroscopic properties of the films such as: hydrophobicity and hydrophilicity were established. - Highlights: • Hybrid organo-polymer silicon films deposited by RF plasma on silicon substrates. • FTIR and XPS reveal porosity by interpreting bonding between Si and –O. • Quantification of nano and microporosity are identified with bonding of Si with –O

  7. Preparation and characterization of ethylenediamine and cysteamine plasma polymerized films on piezoelectric quartz crystal surfaces for a biosensor

    International Nuclear Information System (INIS)

    Mutlu, Selma; Coekeliler, Dilek; Shard, Alex; Goktas, Hilal; Ozansoy, Berna; Mutlu, Mehmet

    2008-01-01

    This paper describes a method for the modification of quartz crystal surfaces to be used as a transducer in biosensors that allow recognition and quantification of certain biomolecules (antibodies, enzymes, proteins, etc). Quartz crystal sensors were modified by a plasma based electron beam generator in order to detect the level of the toxin histamine within biological liquids (blood, serum) and food (wine, cheese, fish etc.). Cysteamine and ethylenediamine were used as precursors in the plasma. After each modification step, the layers on the quartz crystal were characterized by frequency measurements. Modified surfaces were also characterized by contact angle, X-ray photoelectron spectroscopy and atomic force microscopy to determine the physical and chemical characteristics of the surfaces after each modification. Finally, the performance of the sensors were tested by the response to histamine via frequency shifts. The frequency shifts of the sensors prepared by plasma polymerization of ethylenediamine and cysteamine were approximately 3230 Hz and 5630 Hz, respectively, whereas the frequency change of the unmodified crystal surface was around 575 Hz

  8. Evidence of coexistence of micro and nanoporosity of organo-silica polymeric films deposited on silicon by plasma deposition

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, Viswas, E-mail: vishwas.purohit@gmail.com [Laboratoire Environnment et Mineralurgie, UMR 7569 CNRS, INPL-ENSG, BP.40, 54501 Vandoeuvre-les-Nancy (France); Mielczarski, Ela; Mielczarski, Jerzy A. [Laboratoire Environnment et Mineralurgie, UMR 7569 CNRS, INPL-ENSG, BP.40, 54501 Vandoeuvre-les-Nancy (France); Akesso, Laurent [Teer Coatings Ltd., Droitwich, Worcestershire WR9 9AS (United Kingdom)

    2013-09-16

    A range of hybrid, SiOCH films were deposited on silicon substrates within a radio frequency plasma reactor using hexamethyldisiloxane (HMDSO) as a precursor. The plasma polymerized films were deposited at various HMDSO/argon/oxygen ratios. The composition and structure, at microscopic and nanoscopic levels, of the deposited films were determined by external reflection and transmission Fourier Transform Infrared (FTIR) spectroscopy as well as by X-Ray Photoelectron Spectroscopy (XPS). The content of carbon and oxygen in films were found to be inversely proportional to each other. XPS results showed that the outermost surface of the deposited films are nanoporous and coexist with microporosity which was revealed by electron microscopy. The structure of deposited coatings is anisotropic as was documented by polarized external reflection FTIR spectroscopy. Several correlations between the film chemical composition, surface structure, and macroscopic properties of the films such as: hydrophobicity and hydrophilicity were established. - Highlights: • Hybrid organo-polymer silicon films deposited by RF plasma on silicon substrates. • FTIR and XPS reveal porosity by interpreting bonding between Si and –O. • Quantification of nano and microporosity are identified with bonding of Si with –O.

  9. Heat treatment and aging effect on the structural and optical properties of plasma polymerized 2,6-diethylaniline thin films

    International Nuclear Information System (INIS)

    Matin, Rummana; Bhuiyan, A.H.

    2012-01-01

    The monomer, 2,6-diethylaniline has been used to deposit plasma polymerized 2,6-diethylaniline (PPDEA) thin films at room temperature on to glass substrates by a capacitively coupled parallel plate glow discharge reactor. A comparative analysis on the changes of morphological, structural and optical properties of as-deposited, heat treated and aged PPDEA thin films is ascertained. Scanning electron microscopy shows uniform and pinhole free surface of PPDEA thin films and no significant difference in the surface morphology is observed due to heat treatment. Electron dispersive X-ray and Fourier transform infrared spectroscopic investigations indicate some structural rearrangement in PPDEA thin films due to heat treatment. Differential thermal analysis, thermogravimetric analysis and differential thermogravimetric analysis suggest that the PPDEA is thermally stable up to about 580 K. The study on the optical absorption spectra of as-deposited, heat treated and aged PPDEA thin films of different thicknesses lead to the determination of the allowed direct and indirect transition energies ranging from 3.63 to 2.73 and 2.38 to 1.26 eV respectively. Urbach energy, steepness parameter and extinction coefficient are also assessed. It is observed that the optical parameters of as-deposited PPDEA thin films change due to heat treatment and do not change appreciably due to aging. - Highlights: ► Heat treatment and aging effect of plasma polymerized 2,6-diethylaniline thin films. ► The surface morphology of PPDEA is found uniform for all types of sample. ► Heat treatment introduces some elemental and structural rearrangement. ► The thermal stability is found up to about 580 K. ► Optical parameters were changed for heat treatment but not markedly for aging.

  10. Atmospheric pressure plasma polymerization of 1,3-butadiene for hydrophobic finishing of textile substrates

    International Nuclear Information System (INIS)

    Samanta, Kartick K; Jassal, Manjeet; Agrawal, Ashwini K

    2010-01-01

    Atmospheric pressure plasma processing of textile has both ecological and economical advantages over the wet-chemical processing. However, reaction in atmospheric pressure plasma has important challenges to be overcome before it can be successfully used for finishing applications in textile. These challenges are (i) generating stable glow plasma in presence liquid/gaseous monomer, and (ii) keeping the generated radicals active in the presence of contaminants such as oxygen and air. In this study, a stable glow plasma was generated at atmospheric pressure in the mixture of gaseous reactive monomer-1,3-butadiene and He and was made to react with cellulosic textile substrate. After 12 min of plasma treatment, the hydrophilic surface of the cellulosic substrate turned into highly hydrophobic surface. The hydrophobic finish was found to be durable to soap washing. After soap washing, a water drop of 37 μl took around 250 s to get absorbed in the treated sample compared to 0 . Both top and bottom sides of the fabric showed similar hydrophobic results in terms of water absorbency and contact angle. The results may be attributed to chemical reaction of butadiene with the cellulosic textile substrate. The surface characterization of the plasma modified samples under SEM and AFM revealed modification of the surface under <100 nm. The results showed that atmospheric pressure plasma can be successfully used for carrying out reaction of 1,3-butadiene with cellulosic textile substrates for producing hydrophobic surface finish.

  11. Heparin molecularly imprinted polymer thin flm on gold electrode by plasma-induced graft polymerization for label-free biosensor.

    Science.gov (United States)

    Orihara, Kouhei; Hikichi, Atsushi; Arita, Tomohiko; Muguruma, Hitoshi; Yoshimi, Yasuo

    2018-03-20

    Heparin, a highly sulfated glycosaminoglycan, is an important biomaterial having biological and therapeutic functionalities such as anticoagulation, regeneration, and protein stabilization. This study addresses a label-free quartz crystal microbalance (QCM) biosensor for heparin detection based on a macromolecularly imprinted polymer (MIP) as an artificial recognition element. We demonstrate the novel strategy for MIP in the form of thin film on a gold (Au) electrode with the plasma-induced graft polymerization (PIP) technique. The procedure of PIP is as follows: (i) Hexamethyldisiloxane plasma-polymerized thin film (PPF) as a pre-coating scaffold of active species for PIP (post-polymerization) is deposited on an Au electrode. (ii) The PPF/Au electrode is soaked in an water solution containing heparin (template), (2-(methacryloxy)-ethyl)trimethylammonium chloride acrylamide (functional monomer), acrylamide, and N,N-methylenebisacrylamide (crosslinker). Double bonds of monomer and crosslinker attacked by residually active species in pre-coating PPF cause radical chain reaction. Consequently, a growing polymer network of 20 nm thickness of PIP-MIP thin film is formed and grafted on the PPF/Au surface. (iii) The PIP-MIP/PPF/Au is washed by sodium chloride solution so as to remove the template. Non-imprinted polymer (NIP) is carried out like the same procedure without a template. The AFM, XPS, and QCM measurements show that the PIP process facilitates macromolecularly surface imprinting of template heparin where the template is easily removed and is rapidly rebound to PIP-MIP without a diffusional barrier. The heparin-PIP-MIP specifically binds to heparin compared with heparin analog chondroitin sulfate C (selective factor: 4.0) and a detectable range of heparin in the presence of CS (0.1 wt%) was 0.001-0.1 wt%. The PIP-NIP does not show selectivity between them. The evaluated binding kinetics are association (k a  = 350 ± 100 M -1  s -1

  12. Plasma energy recycle and conversion of polymeric (MSW) waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Knight, Richard; Grossman, Elihu D.

    2000-12-05

    Final report summarizing research project results of studies of the thermal plasma recycling of polymers, including polyethylene and polypropylene. High levels of recovery of monomers were obtained from the process developed under this study.

  13. Ethylene- and diethylene glycol metabolism, toxicity and treatment

    International Nuclear Information System (INIS)

    Wiener, H.L.

    1986-01-01

    Each year numerous men and domestic animals suffer from ethylene glycol (EG) poisoning. The present approach to treating EG poisoning by administering ethanol is aimed at preventing the oxidation of EG to glycolate, the toxic mediator. When treatment is delayed or the amount of EG consumed is large, successful treatment is rarely obtained, since the concentration of glycolate becomes excessive. In an effort to develop a better approach to treating EG poisoning, studies were conducted to determine the feasibility of using pig liver glycolic acid oxidase (GAO) as a means of enzyme therapy in male rats receiving EG. Pig liver GAO was active in vitro in rat blood, oxidizing glycolate to glyoxylate. When injected intravenously into male rats, GAO had an approximate half-life of twenty five minutes and its elimination followed first order kinetics. Despite activity in vitro, native pig liver GAO did not display detectable activity in vivo. Diethylene glycol (DEG) when ingested also results in toxicity. The metabolism and toxicity of DEG was investigated in male Wistar rats using [ 14 C]-DEG synthesized from [U- 14 C]-EG and ethylene oxide and purified by high performance liquid chromatography. (2-Hydroxyethoxy)acetic acid (HEAA) was identified as the major product of DEG oxidation. These results suggest that the treatment of DEG poisoning should follow the same regimen as treatment for EG poisoning

  14. Atmospheric pressure plasma polymerization of 1,3-butadiene for hydrophobic finishing of textile substrates

    Energy Technology Data Exchange (ETDEWEB)

    Samanta, Kartick K; Jassal, Manjeet; Agrawal, Ashwini K, E-mail: ashwini@smita-iitd.co, E-mail: manjeet.jassal@smita-iitd.co [Smart and Innovative Textile Materials Group (SMITA), Department of Textile Technology, Indian Institute of Technology, Hauz Khas, New Delhi-110016 (India)

    2010-02-01

    Atmospheric pressure plasma processing of textile has both ecological and economical advantages over the wet-chemical processing. However, reaction in atmospheric pressure plasma has important challenges to be overcome before it can be successfully used for finishing applications in textile. These challenges are (i) generating stable glow plasma in presence liquid/gaseous monomer, and (ii) keeping the generated radicals active in the presence of contaminants such as oxygen and air. In this study, a stable glow plasma was generated at atmospheric pressure in the mixture of gaseous reactive monomer-1,3-butadiene and He and was made to react with cellulosic textile substrate. After 12 min of plasma treatment, the hydrophilic surface of the cellulosic substrate turned into highly hydrophobic surface. The hydrophobic finish was found to be durable to soap washing. After soap washing, a water drop of 37 {mu}l took around 250 s to get absorbed in the treated sample compared to < 1 s in the untreated samples. The plasma modified samples showed water contact angle of around 134{sup 0}. Both top and bottom sides of the fabric showed similar hydrophobic results in terms of water absorbency and contact angle. The results may be attributed to chemical reaction of butadiene with the cellulosic textile substrate. The surface characterization of the plasma modified samples under SEM and AFM revealed modification of the surface under <100 nm. The results showed that atmospheric pressure plasma can be successfully used for carrying out reaction of 1,3-butadiene with cellulosic textile substrates for producing hydrophobic surface finish.

  15. Tailoring the surface properties of polypropylene films through cold atmospheric pressure plasma (CAPP) assisted polymerization and immobilization of biomolecules for enhancement of anti-coagulation activity

    International Nuclear Information System (INIS)

    Navaneetha Pandiyaraj, K.; Ram Kumar, M.C.; Arun Kumar, A.; Padmanabhan, P.V.A.; Deshmukh, R.R.; Bah, M.; Ismat Shah, S.; Su, Pi-Guey; Halleluyah, M.; Halim, A.S.

    2016-01-01

    Graphical abstract: - Highlights: • Developed low cost cold atmospheric plasma reactor for plasma polymerization technique. • Surface of the PP film was modified by grafting of AAc and PEG by CAPP polymerization. • Biomolecules of chitosan, insulin and heparin were immobilized on surface of PEG-AAc grafted PP films. • The surface modified PP films were characterized by various techniques. • The plasma polymerized and immobilized film reveals substantial blood compatibility. - Abstract: Enhancement of anti-thrombogenic properties of polypropylene (PP) to avert the adsorption of plasma proteins (fibrinogen and albumin), adhesion and activation of the platelets are very important for vast biomedical applications. The cold atmospheric pressure plasma (CAPP) assisted polymerization has potential to create the specific functional groups such as O−C=O, C=O, C−N and S−S. on the surface of polymeric films using selective precursor in vapour phase to enhance anti-thrombogenic properties. Such functionalized polymeric surfaces would be suitable for various biomedical applications especially to improve the blood compatibility. The eventual aspiration of the present investigation is to develop the biofunctional coating onto the surface of PP films using acrylic acid (AAc) and polyethylene glycol (PEG) as a precursor in a vapour phase by incorporating specific functional groups for immobilization of biomolecules such as heparin (HEP), chitosan (CHI) and insulin (INS) on the surface of plasma modified PP films. The surface properties such as hydrophilicity, chemical composition, surface topography of the surface modified PP films were analyzed by contact angle (CA), Fourier transform infrared spectroscopy (FTIR), X-ray photo electron spectroscopy (XPS) and atomic force microscopy (AFM). Furthermore the anti-thrombogenic properties of the surface modified PP films were studied by in vitro tests which include platelet adhesion and protein adsorption analysis. It was

  16. Tailoring the surface properties of polypropylene films through cold atmospheric pressure plasma (CAPP) assisted polymerization and immobilization of biomolecules for enhancement of anti-coagulation activity

    Energy Technology Data Exchange (ETDEWEB)

    Navaneetha Pandiyaraj, K., E-mail: dr.knpr@gmail.com [Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, L& T By Pass, Chinniyam Palayam (Post), Coimbatore 641062 (India); Ram Kumar, M.C.; Arun Kumar, A. [Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, L& T By Pass, Chinniyam Palayam (Post), Coimbatore 641062 (India); Padmanabhan, P.V.A. [PSN College of Engineering and Technology, Tirunelveli 627 152 (India); Deshmukh, R.R. [Department of Physics, Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Bah, M.; Ismat Shah, S. [Department of Physics and Astronomy, Department of Materials Science and Engineering, University of Delaware, 208 Dupont Hall, Newark (United States); Su, Pi-Guey [Department of Chemistry, Chinese Culture University, Taipei 111, Taiwan (China); Halleluyah, M.; Halim, A.S. [School of Medical Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2016-05-01

    Graphical abstract: - Highlights: • Developed low cost cold atmospheric plasma reactor for plasma polymerization technique. • Surface of the PP film was modified by grafting of AAc and PEG by CAPP polymerization. • Biomolecules of chitosan, insulin and heparin were immobilized on surface of PEG-AAc grafted PP films. • The surface modified PP films were characterized by various techniques. • The plasma polymerized and immobilized film reveals substantial blood compatibility. - Abstract: Enhancement of anti-thrombogenic properties of polypropylene (PP) to avert the adsorption of plasma proteins (fibrinogen and albumin), adhesion and activation of the platelets are very important for vast biomedical applications. The cold atmospheric pressure plasma (CAPP) assisted polymerization has potential to create the specific functional groups such as O−C=O, C=O, C−N and S−S. on the surface of polymeric films using selective precursor in vapour phase to enhance anti-thrombogenic properties. Such functionalized polymeric surfaces would be suitable for various biomedical applications especially to improve the blood compatibility. The eventual aspiration of the present investigation is to develop the biofunctional coating onto the surface of PP films using acrylic acid (AAc) and polyethylene glycol (PEG) as a precursor in a vapour phase by incorporating specific functional groups for immobilization of biomolecules such as heparin (HEP), chitosan (CHI) and insulin (INS) on the surface of plasma modified PP films. The surface properties such as hydrophilicity, chemical composition, surface topography of the surface modified PP films were analyzed by contact angle (CA), Fourier transform infrared spectroscopy (FTIR), X-ray photo electron spectroscopy (XPS) and atomic force microscopy (AFM). Furthermore the anti-thrombogenic properties of the surface modified PP films were studied by in vitro tests which include platelet adhesion and protein adsorption analysis. It was

  17. Plasma dye coating as straightforward and widely applicable procedure for dye immobilization on polymeric materials.

    Science.gov (United States)

    De Smet, Lieselot; Vancoillie, Gertjan; Minshall, Peter; Lava, Kathleen; Steyaert, Iline; Schoolaert, Ella; Van De Walle, Elke; Dubruel, Peter; De Clerck, Karen; Hoogenboom, Richard

    2018-03-16

    Here, we introduce a novel concept for the fabrication of colored materials with significantly reduced dye leaching through covalent immobilization of the desired dye using plasma-generated surface radicals. This plasma dye coating (PDC) procedure immobilizes a pre-adsorbed layer of a dye functionalized with a radical sensitive group on the surface through radical addition caused by a short plasma treatment. The non-specific nature of the plasma-generated surface radicals allows for a wide variety of dyes including azobenzenes and sulfonphthaleins, functionalized with radical sensitive groups to avoid significant dye degradation, to be combined with various materials including PP, PE, PA6, cellulose, and PTFE. The wide applicability, low consumption of dye, relatively short procedure time, and the possibility of continuous PDC using an atmospheric plasma reactor make this procedure economically interesting for various applications ranging from simple coloring of a material to the fabrication of chromic sensor fabrics as demonstrated by preparing a range of halochromic materials.

  18. Physicochemical properties and enhanced cellullar responses of biocompatible polymeric scaffolds treated with atmospheric pressure plasma using O2 gas

    International Nuclear Information System (INIS)

    Lee, Hyun-Uk; Park, So-Young; Kang, Yoon-Hee; Jeong, Se-Young; Choi, Sae-Hae; Jahng, Yoon-Young; Chung, Gook-Hyun; Kim, Moon-Bum; Cho, Chae-Ryong

    2011-01-01

    Biocompatible polymeric scaffolds were fabricated by mixing 5 wt.% poly(ε-caprolactone) (P) with 4 wt.% gelatin (G) and 1.6 wt.% Dulbecco's modified Eagle's medium containing 10% fetal bovine serum (D). These PGD scaffolds were also treated with atmospheric pressure (AP) plasma using O 2 reactive gas (to create O-PGD scaffolds). The physicochemical and mechanical properties of the PGD scaffolds were characterized by in vitro biodegradability tests, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, contact angle measurements, and tensile strength measurements. The wettability and hydrophilic properties of the scaffold surface were improved remarkably by adding G and D to P, and by subsequent oxygen-assisted AP plasma treatment. An MTT assay, a cell attachment efficiency assay, scanning electron microscopy, and confocal microscopy revealed that Chinese Hamster Ovary (CHO)-K1 cells exhibited higher cell attachment and viability on the PGD and O-PGD scaffolds than on the P and PG scaffolds. Furthermore, the long-term viability of the CHO cells on the PGD and O-PGD scaffolds without exchanging the cell culture media was significantly improved compared to their viability on the P and PG scaffolds. Overall, the PGD and O-PGD scaffolds are expected to be useful as cell growth supporting biomaterials in tissue engineering.

  19. Analysis of the polymeric film and fine dust obtained in plasma of acetylene and acetylene-nitrogen

    International Nuclear Information System (INIS)

    Rojas, Andres F; Ortiz, Jairo A; Devia Alfonso

    1998-01-01

    The results are presented from the resistance analyses to the corrosion of the polymeric covering obtained in plasma of acetylene, on a substrata of aluminum alloy, with the techniques of metallographic analysis, infrared and electrochemical, as much for the fine dust as for the grown film on aluminum. Also, the results of the electrochemical test of polarization made to these films will be shown, which demonstrated an improvement of 2.6 and 4.6 times in the resistance to the corrosion when the material treaty is exposed NaCl 0.2 N and Na H2 PO4 01 M, respectively, in comparison with the substrata without recovering. For the movie obtained in acetylene /nitrogen plasma on steel 1016 the micrographs of the superficial structure of the material they will be shown before and after being treated, which were used to measure the thickness of the cover; also, it will be given to know the results of the tests of adhesion and qualitative analysis of resistance before diverse chemical agents (such as: Benzene, Toluene, H2SO4, HNO3, NaCl, CACO3 NaOH and KOH) and the resistance results are presented from the cover to them

  20. Detailed investigation of optoelectronic and microstructural properties of plasma polymerized cyclohexane thin films: Dependence on the radiofrequency power

    International Nuclear Information System (INIS)

    Manaa, C.; Bouaziz, L.; Lejeune, M.; Zellama, K.; Benlahsen, M.; Kouki, F.; Mejatty, M.; Bouchriha, H.

    2015-01-01

    Optical properties of polymerized cyclohexane films deposited by radiofrequency plasma enhanced chemical vapor deposition technique at different radiofrequency powers onto glass and silicon substrates, are studied and correlated with the microstructure of the films, using a combination of atomic force microscopy, Raman and Fourier Transformer Infrared spectroscopy and optical measurements. The optical constants such as refractive index n, dielectric permittivity ε and extinction k and absorption α coefficients, are extracted from transmission and reflection spectra through the commercial software CODE. These constants lead, by using common theoretical models as Cauchy, Lorentz, Tauc and single effective oscillator, to the determination of the static refractive index n s and permittivity ε s , the plasma frequency ω p , the carrier density to effective mass ratio N/m e * , the optical conductivity σ oc , the optical band gap E g and the oscillation and dispersion energies E 0 and E d , respectively. We find that n, ε s , ω p , N/m e * , E d , increase with radiofrequency power, while E g and E 0 decrease in the same range of power. These results are well correlated with those obtained from atomic force microscopy, Raman and infrared measurements. They also indicate that the increase of the radiofrequency power promotes the fragmentation of the precursor and increases the carbon C-sp 2 hybridization proportion, which results in an improvement of the optoelectronic properties of the films

  1. Biosensor based on laccase immobilized on plasma polymerized allylamine/carbon electrode

    Energy Technology Data Exchange (ETDEWEB)

    Ardhaoui, Malika, E-mail: malika.ardhaoui@ucd.ie [Laboratoire de Génie des Procédés Plasma et Traitements de Surface, Université Pierre et Marie Curie-Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris (France); Laboratoire Charles Friedel, CNRS UMR 7223, Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Surface Engineering Research Group, School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Belfield, Dublin 4 (Ireland); Bhatt, Sudhir [Laboratoire de Génie des Procédés Plasma et Traitements de Surface, Université Pierre et Marie Curie-Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris (France); Zheng, Meihui [Laboratoire Charles Friedel, CNRS UMR 7223, Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Dowling, Denis [Surface Engineering Research Group, School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Belfield, Dublin 4 (Ireland); Jolivalt, Claude [Laboratoire Charles Friedel, CNRS UMR 7223, Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Khonsari, Farzaneh Arefi [Laboratoire de Génie des Procédés Plasma et Traitements de Surface, Université Pierre et Marie Curie-Chimie ParisTech, 11 rue Pierre et Marie Curie, 75231 Paris (France)

    2013-08-01

    In this work, a simple and rapid method was used to functionalize carbon electrode in order to efficiently immobilize laccase for biosensor application. A stable allylamine coating was deposited using a low pressure inductively excited RF tubular plasma reactor under mild plasma conditions (low plasma power (10 W), few minutes) to generate high density amine groups (N/C ratio up to 0.18) on rough carbon surface electrodes. The longer was the allylamine plasma deposition time; the better was the surface coverage. Laccase from Trametes versicolor was physisorbed and covalently bound to these allylamine modified carbon surfaces. The laccase activities and current outputs measured in the presence of 2,2′-azinobis-(3-ethylbenzothiazole-6-sulfonic acid) (ABTS) showed that the best efficiency was obtained for electrode plasma coated during 30 min. They showed also that for all the tested electrodes, the activities and current outputs of the covalently immobilized laccases were twice higher than the physically adsorbed ones. The sensitivity of these biocompatible bioelectrodes was evaluated by measuring their catalytic efficiency for oxygen reduction in the presence of ABTS as non-phenolic redox substrate and 2,6-dimethoxyphenol (DMP) as phenolic one. Sensitivities of around 4.8 μA mg{sup −1} L and 2.7 μA mg{sup −1} L were attained for ABTS and DMP respectively. An excellent stability of this laccase biosensor was observed for over 6 months. - Highlights: • Low pressure plasma was used to generate stable allylamine coating. • Laccase from Trametes versicolor was physisorbed and covalently immobilized. • Best biosensor efficiency obtained for the covalently immobilized laccases • Sensitivities of 4.8 μA mg{sup −1} L and 2.7 μA mg{sup −1} L for ABTS and DMP respectively.

  2. Plasma-initiated polymerization of chitosan-based CS-g-P(AM-DMDAAC) flocculant for the enhanced flocculation of low-algal-turbidity water.

    Science.gov (United States)

    Sun, Yongjun; Zhu, Chengyu; Sun, Wenquan; Xu, Yanhua; Xiao, Xuefeng; Zheng, Huaili; Wu, Huifang; Liu, Cuiyun

    2017-05-15

    In this work, a highly efficient and environmentally friendly chitosan-based graft flocculant, namely, acrylamide- and dimethyl diallyl ammonium chloride-grafted chitosan [CS-g-P(AM-DMDAAC)], was prepared successfully through plasma initiation. FTIR results confirmed the successful polymerization of CS-g-P(AM-DMDAAC) and P(AM-DMDAAC). P(AM-DMDAAC) was the copolymer of acrylamide- and dimethyl diallyl ammonium chloride. SEM results revealed that a densely cross-linked network structure formed on the surface. XRD results verified that the ordered crystal structure of chitosan in CS-g-P(AM-DMDAAC) was changed into an amorphous structure after plasma-induced polymerization. The flocculation results of low-algal-turbidity water further showed the optimal flocculation efficiency of turbidity removal rate, COD removal rate, and Chl-a removal rate were 99.02%, 96.11%, and 92.20%, respectively. The flocculation efficiency of CS-g-P(AM-DMDAAC) were significantly higher than those obtained by cationic polyacrylamide (CPAM) and Polymeric aluminum and iron (PAFC). This work provided a valuable basis for the design of eco-friendly naturally modified polymeric flocculants to enhance the flocculation of low-algal-turbidity water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Aging effects of plasma polymerized ethylenediamine (PPEDA) thin films on cell-adhesive implant coatings

    International Nuclear Information System (INIS)

    Testrich, H.; Rebl, H.; Finke, B.; Hempel, F.; Nebe, B.; Meichsner, J.

    2013-01-01

    Thin plasma polymer films from ethylenediamine were deposited on planar substrates placed on the powered electrode of a low pressure capacitively coupled 13.56 MHz discharge. The chemical composition of the plasma polymer films was analyzed by Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) as well as by X-ray photoelectron spectroscopy (XPS) after derivatization of the primary amino groups. The PPEDA films undergo an alteration during the storage in ambient air, particularly, due to reactions with oxygen. The molecular changes in PPEDA films were studied over a long-time period of 360 days. Simultaneously, the adhesion of human osteoblast-like cells MG-63 (ATCC) was investigated on PPEDA coated corundum blasted titanium alloy (Ti-6Al-4V), which is applied as implant material in orthopedic surgery. The cell adhesion was determined by flow cytometry and the cell shape was analyzed by scanning electron microscopy. Compared to uncoated reference samples a significantly enhanced cell adhesion and proliferation were measured for PPEDA coated samples, which have been maintained after long-time storage in ambient air and additional sterilization by γ−irradiation. - Highlights: • Development of cell-adhesive nitrogen-rich coatings for biomedical applications. • Plasma polymer films from low pressure 13.56 MHz discharge in argon-ethylenediamine. • Enhanced osteoblast adhesion/proliferation on coated implant material (Ti-6Al-4V). • Despite film aging over 360 days the enhanced cell adhesion of the coating remains. • No influence of additional y-sterilization on the enhanced cell adhesion

  4. Controlled Systemic Delivery by Polymeric Implants Enhances Tissue and Plasma Curcumin Levels Compared with Oral Administration

    Science.gov (United States)

    Bansal, Shyam S.; Kausar, Hina; Vadhanam, Manicka V.; Ravoori, Srivani; Gupta, Ramesh C.

    2012-01-01

    Curcumin possess potent anti-inflammatory and anti-proliferative activities but with poor biopharmaceutical attributes. To overcome these limitations, curcumin implants were developed and tissue (plasma, brain and liver) curcumin concentrations were measured in female ACI rats for 3 months. Biological efficacy of tissue levels achieved was analyzed by modulation of hepatic cytochromes. Curcumin implants exhibited diffusion-mediated biphasic release pattern with ~2-fold higher in vivo release as compared to in vitro. Plasma curcumin concentration from implants was ~3.3 ng/ml on day 1 which dropped to ~0.2 ng/ml after 3 months whereas only 0.2–0.3 ng/ml concentration was observed from 4–12 days with diet and was undetected subsequently. Almost 10 fold higher curcumin levels were observed in brain on day 1 from implants compared with diet (30.1±7.3 vs 2.7±0.8 ng/g) and were higher even after 90 days (7.7±3.8 vs 2.2±0.8 ng/g). Although, curcumin levels were similar in liver from both the routes (~25–30 ng/g from day 1–4 and ~10–15 ng/g at 90 days), implants were more efficacious in altering hepatic CYP1A1 levels and CYP3A4 activity at ~28 fold lower doses. Curcumin implants provided much higher plasma and tissue concentrations and are a viable alternative for delivery of curcumin to various organs like brain. PMID:22227368

  5. Gas barrier properties of hydrogenated amorphous carbon films coated on polyethylene terephthalate by plasma polymerization in argon/n-hexane gas mixture

    Energy Technology Data Exchange (ETDEWEB)

    Polonskyi, Oleksandr; Kylián, Ondřej, E-mail: ondrej.kylian@gmail.com; Petr, Martin; Choukourov, Andrei; Hanuš, Jan; Biederman, Hynek

    2013-07-01

    Hydrogenated amorphous carbon thin films were deposited by RF plasma polymerization in argon/n-hexane gas mixture on polyethylene terephthalate (PET) foils. It was found that such deposited films may significantly improve the barrier properties of PET. It was demonstrated that the principal parameter that influences barrier properties of such deposited films towards oxygen and water vapor is the density of the coatings. Moreover, it was shown that for achieving good barrier properties it is advantageous to deposit coatings with very low thickness. According to the presented results, optimal thickness of the coating should not be higher than several tens of nm. - Highlights: • a-C:H films were prepared by plasma polymerization in Ar/n-hexane atmosphere. • Barrier properties of coatings are dependent on their density and thickness. • Highest barrier properties were observed for films with thickness 15 nm.

  6. Hydrophilic film polymerized on the inner surface of PMMA tube by an atmospheric pressure plasma jet

    Science.gov (United States)

    Yin, Mengmeng; Huang, Jun; Yu, Jinsong; Chen, Guangliang; Qu, Shanqing

    2017-07-01

    Polymethyl methacrylate (PMMA) tube is widely used in biomedical and mechanical engineering fields. However, it is hampered for some special applications as the inner surface of PMMA tube exhibts a hydrophobic characteristic. The aim of this work is to explore the hydrophilic modification of the inner surface of the PMMA tubes using an atmospheric pressure plasma jet (APPJ) system that incorporates the acylic acid monomer (AA). Polar groups were grafted onto the inner surface of PMMA tube via the reactive radicals (•OH, •H, •O) generated in the Ar/O2/AA plasma, which were observed by the optical emission spectroscopy (OES). The deposition of the PAA thin layer on the PMMA surface was verified through the ATR-FTIR spectra, which clearly showed the strengthened stretching vibration of the carbonyl group (C=O) at 1700 cm-1. The XPS data show that the carbon ratios of C-OH/R and COOH/R groups increased from 9.50% and 0.07% to 13.49% and 17.07% respectively when a discharge power of 50 W was used in the APPJ system. As a result, the static water contat angle (WCA) of the modified inner surface of PMMA tube decreased from 100° to 48°. Furthermore, the biocompatibility of the APP modified PMMA tubes was illustrated by the study of the adhesion of the cultured MC3T3-E1 osteocyte cells, which exhibted a significantly enhanced adhesion density.

  7. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyun Suk; Ko, Yeong Mu; Shim, Jae Won [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of); Lim, Yun Kyong; Kook, Joong-Ki [Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Cho, Dong-Lyun [School of Applied Chemical Engineering and Center for Functional Nano Fine Chemicals, Chonnam National University, Gwangju (Korea, Republic of); Kim, Byung Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of)

    2010-11-01

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH{sub 2} of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  8. In vitro cell culture, platelet adhesion tests and in vivo implant tests of plasma-polymerized para-xylene films

    International Nuclear Information System (INIS)

    Chou, Chia-Man; Yeh, Chou-Ming; Chung, Chi-Jen; He, Ju-Liang

    2013-01-01

    Plasma-polymerized para-xylene (PPX) was developed in a previous study by adjusting the process parameters: pulse frequency of the power supply (ω p ) and para-xylene monomer flow rate (f p ). All the obtained PPX films exhibit an amorphous structure and present hydrophobicity (water contact angle ranging from 98.5° to 121.1°), higher film growth rate and good fibroblast cell proliferation. In this study, in vitro tests (fibroblast cell compatibility and platelet adhesion) and an in vivo animal study were performed by using PPX deposited industrial-grade silicone sheets (IGS) and compared with medical-grade silicone ones (MS), which were commonly manufactured into catheters or drainage tubes in clinical use. The results reveal that PPX deposited at high ω p or high f p , in comparison with MS, exhibit better cell proliferation and clearly shows less cell adhesion regardless of ω p and f p . PPX also exhibit a comparatively lower level of platelet adhesion than MS. In the animal study, PPX-coated IGS result in similar local tissue responses at 3, 7 and 28 days (short-term) and 84 days (long-term) after subcutaneous implantation the abdominal wall of rodents compared with respective responses to MS. These results suggest that PPX-coated industrial-grade silicone is one alternative to high cost medical-grade silicone.

  9. Molecularly imprinted polymeric stir bar: Preparation and application for the determination of naftopidil in plasma and urine samples.

    Science.gov (United States)

    Peng, Jun; Xiao, Deli; He, Hua; Zhao, Hongyan; Wang, Cuixia; Shi, Tian; Shi, Kexin

    2016-01-01

    In this study, molecularly imprinting technology and stir bar absorption technology were combined to develop a microextraction approach based on a molecularly imprinted polymeric stir bar. The molecularly imprinted polymer stir bar has a high performance, is specific, economical, and simple to prepare. The obtained naftopidil-imprinted polymer-coated bars could simultaneously agitate and adsorb naftopidil in the sample solution. The ratio of template/monomer/cross-linker and conditions of template removal were optimized to prepare a stir bar with highly efficient adsorption. Fourier transform infrared spectroscopy, scanning electron microscopy, selectivity, and extraction capacity experiments showed that the molecularly imprinted polymer stir bar was prepared successfully. To utilize the molecularly imprinted polymer stir bar for the determination of naftopidil in complex body fluid matrices, the extraction time, stirring speed, eluent, and elution time were optimized. The limits of detection of naftopidil in plasma and urine sample were 7.5 and 4.0 ng/mL, respectively, and the recoveries were in the range of 90-112%. The within-run precision and between-run precision were acceptable (relative standard deviation bar based microextraction with high-performance liquid chromatography was a convenient, rapid, efficient, and specific method for the precise determination of trace naftopidil in clinical analysis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. In vitro cell culture, platelet adhesion tests and in vivo implant tests of plasma-polymerized para-xylene films

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Chia-Man [Department of Surgery, Taichung Veterans General Hospital, Taiwan, ROC (China); National Yang-Ming University, Taipei, Taiwan, ROC (China); Yeh, Chou-Ming, E-mail: cmchou4301@gmail.com [Taichung Hospital, Department of Health, Executive Yuan, Taiwan, ROC (China); Chung, Chi-Jen [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taiwan, ROC (China); He, Ju-Liang [Department of Materials Science and Engineering, Feng Chia University, Taiwan, ROC (China)

    2013-09-01

    Plasma-polymerized para-xylene (PPX) was developed in a previous study by adjusting the process parameters: pulse frequency of the power supply (ω{sub p}) and para-xylene monomer flow rate (f{sub p}). All the obtained PPX films exhibit an amorphous structure and present hydrophobicity (water contact angle ranging from 98.5° to 121.1°), higher film growth rate and good fibroblast cell proliferation. In this study, in vitro tests (fibroblast cell compatibility and platelet adhesion) and an in vivo animal study were performed by using PPX deposited industrial-grade silicone sheets (IGS) and compared with medical-grade silicone ones (MS), which were commonly manufactured into catheters or drainage tubes in clinical use. The results reveal that PPX deposited at high ω{sub p} or high f{sub p}, in comparison with MS, exhibit better cell proliferation and clearly shows less cell adhesion regardless of ω{sub p} and f{sub p}. PPX also exhibit a comparatively lower level of platelet adhesion than MS. In the animal study, PPX-coated IGS result in similar local tissue responses at 3, 7 and 28 days (short-term) and 84 days (long-term) after subcutaneous implantation the abdominal wall of rodents compared with respective responses to MS. These results suggest that PPX-coated industrial-grade silicone is one alternative to high cost medical-grade silicone.

  11. A hybrid heterojunction with reverse rectifying characteristics fabricated by magnetron sputtered TiOx and plasma polymerized aniline structure

    International Nuclear Information System (INIS)

    Sarma, Bimal K; Pal, Arup R; Bailung, Heremba; Chutia, Joyanti

    2012-01-01

    A TiO x film produced by direct current reactive magnetron sputtering without substrate heating or post-deposition annealing and a plasma polymerized aniline (PPA) structure deposited in the same reactor by a radio-frequency glow discharge without the assistance of a carrier gas are used for the fabrication of a heterojunction. The gas phase discharge is investigated by a Langmuir probe and optical emission spectroscopy. The individual layers and the heterojunction are characterized for structural and optoelectronic properties. PPA has polymer-like structure and texture and is characterized by saturated-unsaturated, branched and crosslinked networks. X-ray photoelectron spectroscopy reveals a slightly reduced TiO x surface, which exhibits near band edge luminescence. The free radicals trapped in PPA readily react with oxygen when exposed to atmosphere. The heterojunction shows reverse rectifying characteristics under dark and ultraviolet (UV) irradiation. The energy levels of TiO x and PPA might exhibit reverse band bending and electrons and holes are accumulated on both sides of the heterojunction. The charge accumulation phenomena at the interface may play a key role in the device performance of a hybrid heterojunction. The current-voltage characteristic of the heterojunction is sensitive to UV light, so the structure may be used for photo-sensing applications. (paper)

  12. Enhanced corrosion resistance and hemocompatibility of biomedical NiTi alloy by atmospheric-pressure plasma polymerized fluorine-rich coating

    Energy Technology Data Exchange (ETDEWEB)

    Li, Penghui; Li, Limin [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Wang, Wenhao [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Division of Spine Surgery, Department of Orthopaedics and Traumatology, Pokfulam, Hong Kong (China); Jin, Weihong [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Liu, Xiangmei [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan, Hubei 430062 (China); Yeung, Kelvin W.K. [Division of Spine Surgery, Department of Orthopaedics and Traumatology, Pokfulam, Hong Kong (China); Chu, Paul K., E-mail: paul.chu@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2014-04-01

    Highlights: • Fluoropolymer is deposited on NiTi alloy via atmospheric-pressure plasma polymerization. • The corrosion resistance of NiTi alloy in SBF and DMEM is evidently improved. • The adsorption ratio of albumin to fibrinogen is increased on the coated surface. • The reduced platelet adhesion number indicates better in vitro hemocompatibility. - Abstract: To improve the corrosion resistance and hemocompatibility of biomedical NiTi alloy, hydrophobic polymer coatings are deposited by plasma polymerization in the presence of a fluorine-containing precursor using an atmospheric-pressure plasma jet. This process takes place at a low temperature in air and can be used to deposit fluoropolymer films using organic compounds that cannot be achieved by conventional polymerization techniques. The composition and chemical states of the polymer coatings are characterized by fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The corrosion behavior of the coated and bare NiTi samples is assessed and compared by polarization tests and electrochemical impedance spectroscopy (EIS) in physiological solutions including simulated body fluids (SBF) and Dulbecco's Modified Eagle's medium (DMEM). The corrosion resistance of the coated NiTi alloy is evidently improved. Protein adsorption and platelet adhesion tests reveal that the adsorption ratio of albumin to fibrinogen is increased and the number of adherent platelets on the coating is greatly reduced. The plasma polymerized coating renders NiTi better in vitro hemocompatibility and is promising as a protective and hemocompatible coating on cardiovascular implants.

  13. Toxicokinetics of diethylene glycol (DEG) in the rat.

    Science.gov (United States)

    Heilmair, R; Lenk, W; Löhr, D

    1993-01-01

    Oral doses of 1 and 5 ml/kg 14C-diethylene glycol (DEG) given to rats were rapidly and almost completely absorbed, the invasion constants being 2.95 h-1 and 4.24 h-1. The kinetics of invasion were determined with the method of residuals (Rowland and Tozer 1989) and by reconstruction of the invasion curves according to Kübler (1970). 14C-DEG was rapidly distributed from the blood into the organs and tissues in the order kidneys > brain > spleen > liver > muscle > fat, i.e. the same order as the blood flow. The relative volume of distribution, app. VD, was determined at 298 ml, indicating distribution over the whole body. After oral doses of 1, 5, and 10 ml 14C-DEG/kg 64, 87, and 91% of 14C activity in rat blood disappeared in 12-16 h with a half-life of 3.4 h and the remaining 9, 5, and 4% with half-lives of 39 h, 45 h, and 49 h. A total of 73-96% of 14C activity in blood was excreted with the urine and 0.7-2.2% with the faeces. From the cumulative urinary excretion kinetics half-lives of 6 h were determined for doses of 1 and 5 ml/kg and 10 h for the dose of 10 ml/kg. After doses of 5 ml/kg and 10 ml/kg 14C-DEG semi-logarithmic plots of elimination rate versus time were constant for 5 and 9 h, respectively, indicating that DEG accelerated its renal elimination by inducing osmotic diuresis. Thereafter urinary excretion followed first order kinetics with elimination half-lives of 3.6 h. After oral doses of 5 ml/kg 14C-DEG given to rats of 336 g body weight with an app. VD of 297 ml, the total clearance of 14C activity was determined at 63 ml/h, and the renal clearance of unmetabolized DEG was 66 ml/h. The ratio of ClDEG to Cl(inulin) = 0.64 indicated that DEG and its metabolite 2-hydroxyethoxyacetate (2-HEAA) were reabsorbed from the tubuli into the blood capillaries. DEG produced metabolic acidosis, which was completely balanced after doses of 1 and 5 ml/kg, but doses greater than 10 ml/kg produced non-compensated metabolic acidosis, hydropic degeneration of the

  14. Visible photoluminescence from plasma-polymerized-organosilicone thin films deposited from HMDSO/O2 induced remote plasma: effect of oxygen fraction

    Science.gov (United States)

    Naddaf, M.; Saloum, S.

    2008-09-01

    Visible photoluminescence (PL) from thin films deposited on silicon wafers by remote plasma polymerization of the hexamethyledisiloxane (HMDSO)/O2 mixture in a radio-frequency hollow cathode discharge reactor has been investigated as a function of different oxygen fractions ( \\chi _{O_2 } =0 , 0.38, 0.61, 0.76 and 0.9). At room temperature, the film deposited at \\chi _{O_2 } =0 exhibits a strong, broad PL band peak centred at around 537.6 nm. A blue shift and a considerable decrease (~one order) in the intensity of the PL peak are observed after the addition of oxygen. Furthermore, in contrast to the film deposited from pure HMDSO, the low temperature (15 K) PL spectra of the film deposited from different HMDSO/O2 mixtures exhibit two separated 'green-blue' and 'yellow-green' PL peaks. The PL behaviour of the deposited films is correlated with their structural and morphological properties, investigated by using Fourier transform infrared, atomic force microscope and contact angle techniques. In addition, it is found from spectrophotometry measurements that the deposited films have relatively low absorption coefficients (in the range 100-500 cm-1) in the spectral range of their PL emission, attractive for possible integrated optics devices.

  15. Visible photoluminescence from plasma-polymerized-organosilicone thin films deposited from HMDSO/O2 induced remote plasma: effect of oxygen fraction

    International Nuclear Information System (INIS)

    Naddaf, M.; Saloum, S.

    2009-01-01

    Visible photoluminescence (PL) from thin films deposited on silicon wafers by remote plasma polymerization of the hexamethyldisiloxane (HMDSO)/O 2 mixture in a radio-frequency hollow cathode discharge reactor has been investigated as a function of different oxygen fractions (χ0 2 0.38, 0.61, 0.76 and 0.9). At room temperature, the film deposited at exhibits a strong, broad PL band peak centred at around 537.6 nm. A blue shift and a considerable decrease (∼one order) in the intensity of the PL peak are observed after the addition of oxygen. Furthermore, in contrast to the film deposited from pure HMDSO, the low temperature (15 K) PL spectra of the film deposited from different HMDSO/O 2 mixtures exhibit two separated green-blue and yellow-green PL peaks. The PL behaviour of the deposited films is correlated with their structural and morphological properties, investigated by using Fourier transform infrared, atomic force microscope and contact angle techniques. In addition, it is found from spectrophotometry measurements that the deposited films have relatively low absorption coefficients (in the range 100-500 cm -1 ) in the spectral range of their PL emission, attractive for possible integrated optics devices. (authors)

  16. Visible photoluminescence from plasma-polymerized-organosilicone thin films deposited from HMDSO/O{sub 2} induced remote plasma: effect of oxygen fraction

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, M; Saloum, S [Department of Physics, Atomic Energy Commission of Syria (AECS), PO Box 6091 Damascus (Syrian Arab Republic)], E-mail: scientific6@aec.org.sy

    2008-09-07

    Visible photoluminescence (PL) from thin films deposited on silicon wafers by remote plasma polymerization of the hexamethyledisiloxane (HMDSO)/O{sub 2} mixture in a radio-frequency hollow cathode discharge reactor has been investigated as a function of different oxygen fractions ({chi}{sub O{sub 2}}=0, 0.38, 0.61, 0.76 and 0.9). At room temperature, the film deposited at ({chi}{sub O{sub 2}}=0 exhibits a strong, broad PL band peak centred at around 537.6 nm. A blue shift and a considerable decrease ({approx}one order) in the intensity of the PL peak are observed after the addition of oxygen. Furthermore, in contrast to the film deposited from pure HMDSO, the low temperature (15 K) PL spectra of the film deposited from different HMDSO/O{sub 2} mixtures exhibit two separated 'green-blue' and 'yellow-green' PL peaks. The PL behaviour of the deposited films is correlated with their structural and morphological properties, investigated by using Fourier transform infrared, atomic force microscope and contact angle techniques. In addition, it is found from spectrophotometry measurements that the deposited films have relatively low absorption coefficients (in the range 100-500 cm{sup -1}) in the spectral range of their PL emission, attractive for possible integrated optics devices.

  17. Visible photoluminescence from plasma-polymerized-organosilicone thin films deposited from HMDSO/O2 induced remote plasma: effect of oxygen fraction

    International Nuclear Information System (INIS)

    Naddaf, M; Saloum, S

    2008-01-01

    Visible photoluminescence (PL) from thin films deposited on silicon wafers by remote plasma polymerization of the hexamethyledisiloxane (HMDSO)/O 2 mixture in a radio-frequency hollow cathode discharge reactor has been investigated as a function of different oxygen fractions (χ O 2 =0, 0.38, 0.61, 0.76 and 0.9). At room temperature, the film deposited at (χ O 2 =0 exhibits a strong, broad PL band peak centred at around 537.6 nm. A blue shift and a considerable decrease (∼one order) in the intensity of the PL peak are observed after the addition of oxygen. Furthermore, in contrast to the film deposited from pure HMDSO, the low temperature (15 K) PL spectra of the film deposited from different HMDSO/O 2 mixtures exhibit two separated 'green-blue' and 'yellow-green' PL peaks. The PL behaviour of the deposited films is correlated with their structural and morphological properties, investigated by using Fourier transform infrared, atomic force microscope and contact angle techniques. In addition, it is found from spectrophotometry measurements that the deposited films have relatively low absorption coefficients (in the range 100-500 cm -1 ) in the spectral range of their PL emission, attractive for possible integrated optics devices

  18. Study of detonation nanodiamond - plasma polymerized hexamethildisiloxan composites for medical application

    International Nuclear Information System (INIS)

    Pramatarova, L D; Krasteva, N A; Radeva, E I; Pecheva, E V; Dimitrova, R P; Hikov, T A; Mitev, D P; Hristova, K T; Altankov, G

    2010-01-01

    The present study reports on how detonation nanodiamond (DND) - plasma poly(hexamethyldisiloxane) composites (PPHMDS) affect osteoblast cell behavior. It has been established that various modified DND nanoparticles (Ag-DND and Si-DND) can be readily integrated into virtually all polymer matrices. In particular, PPHDMS composites have been developed over the past few years because of the variety of their application as medical devices and implants. By incubation of MG-63 osteoblast-like cells on the surface of DND (Ag-DND and Si-DND) - PPHMDS composite, we tested the hypothesis that DND-based polymer composites can influence the adhesion behavior of MG-63 osteoblast-like cells. Morphological and structural characterization of DND, Ag-DND and Si-DND powders was carried out by XRD, HRTEM and EDS. For the study of the composite layers, deposited on cover glass (CG), FTIR spectroscopy has been performed in order to determine if the DND nanofiller can potentially modify the structural and chemical dynamics of the polymer matrix. The kinetic of static water contact angle of composite surfaces as a function of the as-used nanofiller DND's in polymer matrix was measured The results with MG-63 osteoblast-like cells suggest the potential of using DND-based polymer composites for application in engineering implantable scaffolds and devices.

  19. Study of detonation nanodiamond - plasma polymerized hexamethildisiloxan composites for medical application

    Energy Technology Data Exchange (ETDEWEB)

    Pramatarova, L D; Krasteva, N A; Radeva, E I; Pecheva, E V; Dimitrova, R P; Hikov, T A; Mitev, D P; Hristova, K T; Altankov, G, E-mail: lpramat@issp.bas.b

    2010-11-01

    The present study reports on how detonation nanodiamond (DND) - plasma poly(hexamethyldisiloxane) composites (PPHMDS) affect osteoblast cell behavior. It has been established that various modified DND nanoparticles (Ag-DND and Si-DND) can be readily integrated into virtually all polymer matrices. In particular, PPHDMS composites have been developed over the past few years because of the variety of their application as medical devices and implants. By incubation of MG-63 osteoblast-like cells on the surface of DND (Ag-DND and Si-DND) - PPHMDS composite, we tested the hypothesis that DND-based polymer composites can influence the adhesion behavior of MG-63 osteoblast-like cells. Morphological and structural characterization of DND, Ag-DND and Si-DND powders was carried out by XRD, HRTEM and EDS. For the study of the composite layers, deposited on cover glass (CG), FTIR spectroscopy has been performed in order to determine if the DND nanofiller can potentially modify the structural and chemical dynamics of the polymer matrix. The kinetic of static water contact angle of composite surfaces as a function of the as-used nanofiller DND's in polymer matrix was measured The results with MG-63 osteoblast-like cells suggest the potential of using DND-based polymer composites for application in engineering implantable scaffolds and devices.

  20. Fine structures and magnetic properties of FeCo granular thin films with plasma polymerized (C4F8) n matrix

    International Nuclear Information System (INIS)

    Kakizaki, K.; Yasoshima, S.; Choi, K.-K.; Kamishima, K.; Hiratsuka, N.

    2007-01-01

    In this paper a method for polymerization of fluorocarbon gas in argon plasma to obtain a novel granular structure was reported. We prepared granular films where FeCo fine particles were distributed in plasma-polymerized fluorocarbon matrix by a facing-targets RF magnetron sputtering method, and investigated the correlation between their structures and magnetic properties. The magnetization of the films prepared with the partial pressure of fluorocarbon gas between 0 and 1.0 mTorr decreased linearly, because the FeCo content in a unit volume of a film decreased when a polymerized material was used as the matrix. However, the coercivity of the films decreased drastically with increasing the partial pressure of fluorocarbon gas above 0.4 mTorr. This is because the magnetic anisotropy of FeCo particles is decreased by the decrease of grain size. It was confirmed by a TEM observation that the FeCo-(C 4 F 8 ) n films had the granular structure which was constituted by the very fine FeCo particles and the plasma-polymerized fluorocarbon matrix. For the film deposited at the partial pressure of fluorocarbon gas of 0.4 mTorr, the size of FeCo magnetic particles is about 20 nm. On the other hand, the size of FeCo particles is decreased to about 8 nm when the film deposited at the partial pressure of fluorocarbon gas of 0.8 mTorr and its distribution is small

  1. Poly(mono/diethylene glycol n-tetradecyl ether vinyl ethers with Various Molecular Weights as Phase Change Materials

    Directory of Open Access Journals (Sweden)

    Dongfang Pei

    2018-02-01

    Full Text Available At present, research on the relationship of comb-like polymer phase change material structures and their heat storage performance is scarce. Therefore, this relationship from both micro and macro perspectives will be studied in this paper. In order to achieve a high phase change enthalpy, ethylene glycol segments were introduced between the vinyl and the alkyl side chains. A series of poly(mono/diethylene glycol n-tetradecyl ether vinyl ethers (PC14EnVEs (n = 1, 2 with various molecular weights were polymerized by living cationic polymerization. The results of PC14E1VE and PC14E2VE showed that the minimum number of carbon atoms required for side-chain crystallization were 7.7 and 7.2, which were lower than that reported in the literature. The phase change enthalpy 89 J/g (for poly(mono ethylene glycol n-tetradecyl ether vinyl ethers and 86 J/g (for poly(hexadecyl acrylate were approximately equal. With the increase of molecular weight, the melting temperature, the melting enthalpy, and the initial thermal decomposition temperature of PC14E1VE changed from 27.0 to 28.0 °C, from 95 to 89 J/g, and from 264 to 287 °C, respectively. When the number average molar mass of PC14EnVEs exceeded 20,000, the enthalpy values remained basically unchanged. The introduction of the ethylene glycol chain was conducive to the crystallization of alkyl side chains.

  2. [Carcinogenic activity of ethylene oxide and its reaction products 2-chloroethanol, 2-bromoethanol, ethylene glycol and diethylene glycol. III. Research on ethylene glycol and diethylene glycol for carcinogenic effects].

    Science.gov (United States)

    Dunkelberg, H

    1987-03-01

    Ethylene glycol and diethylene glycol were each administered once weekly subcutaneously to groups of 100 female NMRI mice at 3 dosages (30; 10 und 3 mg single dose per mouse). Tricaprylin was used as solvent. The mean total dosage per mouse was 2110.5; 707.0 and 196.2 mg for ethylene glycol and 2029.8; 671.7 and 213.3 mg for diethylene glycol. Neither ethylene glycol nor diethylene glycol induced tumors at the injection site or away from the point of administration.

  3. Plasma-polymerized perfluoro(methylcyclohexane) coating on ethylene propylene diene elastomer surface: Effect of plasma processing condition on the deposition kinetics, morphology and surface energy of the film

    International Nuclear Information System (INIS)

    Tran, N.D.; Dutta, N.K.; Choudhury, N. Roy

    2005-01-01

    Plasma polymerization of perfluoro (methylcyclohexane) was carried out under cold plasma process operated at 13.56 MHz to deposit pore-free, uniform, ultra-thin film on an ethylene propylene diene terpolymer (EPDM) substrate in a view to modify the surface characteristics. The plasma fluoropolymeric films were formed at different plasma treatment times (from 20 s to 16 min), applied powers (20 to 100 W) and precursor flow rates to produce high quality films in a controllable yet tunable fashion. Scanning electron microscopy was employed successfully to characterize the evolution of the morphological feature in the film and also to determine the thickness of the coating. The surface energy of the film was determined by sessile drop method using different solvents as probe liquids. It is observed that a pore-free homogeneous plasma polymer thin film is formed within 20 s of treatment time, however, the morphology of the film depends on the plasma processing conditions, such as plasma power, precursor flow rate and deposition time. With increased time and power at a constant flow rate, the morphology of the film progressively changes from flat smooth to globular and rough. The kinetics and activation energy of the plasma polymer film deposition process were also estimated. The surface energy of the EPDM substrate decreased dramatically with plasma coating, however, it appears to be independent of the treatment time

  4. Characterization of plasma-polymerized 4-vinyl pyridine with silver nanoparticies on poly(ethylene terephthalate) film for anti-microbial properties

    DEFF Research Database (Denmark)

    Jiang, J.; Winther-Jensen, Bjørn; Kjær, Erik Michael

    2006-01-01

    scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Different thicknesses Of poly(4-vinyl pyridine) coating under different plasma polymerization conditions were studied. Silver nanoparticles with diameter around 50nm deposit were precipitated...... on the poly(4-vinyl pyridine) coating by UV irradiation in Silver nitride water solution, in order to enhance the anti-microbial properties. Different kinds of modified PET films were tested for anti-microbial properties against yeast (Debaryomyces hansenii) by using microbiological analyser mu-4200...

  5. Concentration of gadolinium-diethylene triamine pentaacetic acid in human kidney

    International Nuclear Information System (INIS)

    Takeda, Masayuki; Katayama, Yasushi; Tsutsui, Toshiki; Komeyama, Takeshi; Mizusawa, Takaki; Tanikawa, Toshiki; Sato, Shotaro

    1993-01-01

    Although gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) has been used as a contrast material in magnetic resonance imaging, it is known that contrast enhancement effect disappears if the concentration of Gd-DTPA increases beyond some levels. In this study, to evaluate the proper pulse sequences for dynamic magnetic resonance imaging (MRI) in the human kidney, the concentration of Gd-DTPA was quantitatively measured by inductively coupled plasma (ICP) emission spectrometry in human biological samples after administration of Gd-DTPA, and the signal intensity of MRI is the solution of several concentrations of Gd-DTPA was measured. In using a low magnetic field apparatus, signal intensity linearly correlated with the concentration of Gd-DTPA between 0 and 2.0 μmol/g under saturation recovery sequences (flip angle was 60deg or 90deg). Using a high magnetic field apparatus, signal intensity linearly correlated with the concentration of Gd-DTPA between 0 and 2.0 or 3.0 μmol/g under spin echo or gradient-echo sequences. Gd-DTPA concentration of the renal cortex ranged from 0.132 to 0.152 μmol/g tissue at 5 min after intravenous injection of Gd-DTPA 0.05 mmol/kg body weight in 7 patients with adrenal tumor or renal cell cancer, and 1 patient with both urinary bladder cancer and prostatic cancer. Seven of them showed normal renal function and the other had renal insufficiency (GFR 25 ml/min/1.48 m 2 ). Gd-DTPA concentrations of renal medulla and renal cell cancer tissue were 0.123 and 0.108 μmol/g tissue, respectively, at 5 min after intravenous injection of Gd-DTPA 0.05 mmol/kg body weight. These results suggest that the signal intensity of renal cortex, renal medulla, and renal cell cancer tissue may linearly correlate with Gd-DTPA concentration of tissues at 5 min after intravenous injection of Gd-DTPA 0.5 mmol/kg body weight. (author)

  6. Delayed autonomic neuropathy in a patient with diethylene glycol poisoning: a case report.

    Science.gov (United States)

    Kamada, Hiroki; Suzuki, Hideaki; Yamamoto, Saori; Nomura, Ryosuke; Kushimoto, Shigeki

    2017-07-01

    A 72-year-old man presented to our hospital after ingesting insecticide containing approximately 2 mL/kg diethylene glycol, which exceeded the lethal dose of 1 mL/kg. The patient recovered from critical symptoms on acute phase until day 3, but received artificial ventilation for muscle weakness secondary to sensorimotor neuropathy on days 11-54. Even after marked improvement from sensorimotor neuropathy, the patient continued to complain of orthostatic hypotension. Autonomic neuropathy was identified by positive result of a head-up tilt test, and reduction in coefficient of variation of R-R intervals and cardiac iodine-123-metaiodobenzylguanidine uptake for the assessment of cardiac sympathetic activity. The patient's symptoms fully recovered 2 years after the exposure to diethylene glycol. This case shows the first report of delayed autonomic neuropathy after recovery from severe sensorimotor neuropathy, and suggests the importance of continuous monitoring for late-onset neurological complications.

  7. Interomolecular interactions in diluted solutions of potassium iodocuprates (1) in dimethyl ether of diethylene glycol

    International Nuclear Information System (INIS)

    Gorodinskaya, Eh.Ya.; Mel'nikova, N.B.; Yurin, K.V.

    1991-01-01

    The role of donor solvent in the formation of potassium mononuclear iodocuprates (1) in the system CuI-KI-dimethyl ether of diethylene glycol has been considerd. The calculated values of enthalpy, free energy and entropy of viscous flow activation in the range of temperatures 298-318 K for the solutions testify to decomposition of the solvent structure. Negative deviations of mole volumes from the additivity rule characterized strong molecular interaction

  8. Delayed autonomic neuropathy in a patient with diethylene glycol poisoning: a case report

    OpenAIRE

    Kamada, Hiroki; Suzuki, Hideaki; Yamamoto, Saori; Nomura, Ryosuke; Kushimoto, Shigeki

    2017-01-01

    Case A 72‐year‐old man presented to our hospital after ingesting insecticide containing approximately 2 mL/kg diethylene glycol, which exceeded the lethal dose of 1 mL/kg. The patient recovered from critical symptoms on acute phase until day 3, but received artificial ventilation for muscle weakness secondary to sensorimotor neuropathy on days 11–54. Outcome Even after marked improvement from sensorimotor neuropathy, the patient continued to complain of orthostatic hypotension. Autonomic neur...

  9. Surface modification of thermoplastic poly(vinyl alcohol)/saponite nanocomposites via surface-initiated atom transfer radical polymerization enhanced by air dielectric discharges barrier plasma treatment

    International Nuclear Information System (INIS)

    Zhen Weijun; Lu Canhui

    2012-01-01

    To improve the water resistance of thermoplastic poly(vinyl alcohol)/saponite nanocomposites (TPVA), a simple two-step method was developed for the covalent immobilization of atom transfer radical polymerization (ATRP) initiators on the TPVA surfaces enhanced by air dielectric barrier discharges (DBD) plasma treatment, and hydrophobic poly(methyl methacrylate) (PMMA) brushes were then grafted onto the surface of TPVA via surface-initiated atom transfer radical polymerization (SI-ATRP). The chemical composition, morphology and hydrophobicity of the modified TPVA surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), respectively. The water resistance of the surface-functionalized PMMA was evaluated by the contact angle and water adsorption method. It was shown that air DBD plasma treatment activated the TPVA surface and accelerated the immobilization of ATRP initiator on the TPVA surface. Compared with TPVA control, TPVA modified by SI-ATRP can be grafted well-defined and covalently tethered network PMMA brushes onto the surface and the hydrophobicity of TPVA were significantly enhanced.

  10. Correlation between native bonds in a polymeric material and molecular emissions from the laser-induced plasma observed with space and time resolved imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, S. [CRITT Materiaux Alsace, 19 rue de St Junien, 67300 Schiltigheim (France); Laboratoire de Recherche des Monuments Historiques, 29 rue de Paris, 77420 Champs-sur-Marne (France); Institut Charles Sadron, CNRS and University of Strasbourg, 23 rue de Loess, 67034 Strasbourg Cedex (France); Motto-Ros, V.; Ma, Q.L.; Lei, W.Q.; Wang, X.C. [Universite de Lyon, F-69622, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM (France); Pelascini, F.; Surma, F. [CRITT Materiaux Alsace, 19 rue de St Junien, 67300 Schiltigheim (France); Detalle, V., E-mail: vincent.detalle@culture.gouv.fr [Laboratoire de Recherche des Monuments Historiques, 29 rue de Paris, 77420 Champs-sur-Marne (France); Yu, J. [Universite de Lyon, F-69622, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM (France)

    2012-08-15

    Emissions from C{sub 2} molecules and CN radicals in laser-induced plasmas on polymeric materials were observed with time-resolved spectroscopic imaging. More precisely, differential imaging with a pair of narrowband filters (one centered on the emission line and another out of the line) was used to extract emission images of interested molecules or radicals. The correlation between the molecular emission image of the plasma and the molecular structure of the polymer to be analyzed was studied for four different types of materials: polyamide (PA) with native CN bonds, polyethylene (PE) with simple CC bonds, polystyrene (PS) with delocalized double CC bonds, and polyoxymethylene (POM) which neither contains CC nor CN bonds. A clear correlation is demonstrated between emission and molecular structure of the material, allowing the identification of several organic compounds by differential spectroscopic imaging. - Highlights: Black-Right-Pointing-Pointer Plasma imaging method to discriminate different type of polymers. Black-Right-Pointing-Pointer Molecular emissions (CN and C{sub 2}) are spatially and temporally correlated to native bonds. Black-Right-Pointing-Pointer Several formation processes of molecular fragments are observed.

  11. Mechanism of the immobilization of surfactants on polymeric surfaces by means of an argon plasma treatment: Influence of UV radiation

    NARCIS (Netherlands)

    Lens, J.P.; Spaay, B.; Terlingen, J.G.A.; Engbers, G.H.M.; Feijen, Jan

    1999-01-01

    The mechanism of the immobilization of the surfactant sodium 10-undecenoate (C11(:)) on poly(ethylene) (PE) by means of an argon plasma treatment has been investigated. In particular, the influence of the vacuum ultraviolet (UV) radiation emitted by the argon plasma on the immobilization was

  12. Synthesis, recognition and evaluation of molecularly imprinted polymer nanoparticle using miniemulsion polymerization for controlled release and analysis of risperidone in human plasma samples

    International Nuclear Information System (INIS)

    Asadi, Ebadullah; Azodi-Deilami, Saman; Abdouss, Majid; Kordestani, Davood; Rahimi, Alireza; Asadi, Somayeh

    2014-01-01

    We prepared high selective imprinted nanoparticle polymers by a miniemulsion polymerization technique, using risperidone as the template, MAA as the functional monomers, and TRIM as the cross-linker in acetonitrile as solvent. The morphology of the nanoparticles determined by scanning electron microscopy (SEM) images and drug release, binding properties and dynamic light scattering (DLS) of molecularly imprinted polymers (MIPs) were studied. Controlled release of risperidone from nanoparticles was investigated through in 1% wt sodium dodecyl sulfate aqueous solution and by measuring the absorbance by HPLC-UV. The results showed that the imprinted nanoparticles exhibited a higher binding level and slower release rate than non-imprinted nanoparticles, which contributed to interaction of risperidone with imprinted cavities within nanoparticles. Furthermore, the results from HPLC showed good precision (5% for 50.0 µg L -1 ) and recoveries (between 86-91) using MIP from human plasma samples

  13. Diethylene-triamine-penta-acetate administration protocol for radiological emergency medicine in nuclear fuel reprocessing plants.

    Science.gov (United States)

    Jin, Yutaka

    2008-01-01

    Inhalation therapy of diethylene-triamine-penta-acetate (DTPA) should be initiated immediately to workers who have significant incorporation of plutonium, americium or curium in the nuclear fuel reprocessing plant. A newly designed electric mesh nebulizer is a small battery-operated passive vibrating mesh device, in which vibrations in an ultrasonic horn are used to force drug solution through a mesh of micron-sized holes. This nebulizer enables DTPA administration at an early stage in the event of a radiation emergency from contamination from the above radioactive metals.

  14. Effects of plasma polymerized para-xylene intermediate layers on characteristics of flexible organic light emitting diodes fabricated on polyethylene terephthalate substrates

    International Nuclear Information System (INIS)

    Sohn, Sunyoung; Kim, Kyuhyung; Kho, Samil; Jung, Donggeun; Boo, Jin-hyo

    2008-01-01

    Characteristics of flexible organic light emitting diodes (FOLEDs) with the plasma polymerized para-xylene (PPpX) intermediate layer were investigated. For the purpose of reducing moisture permeation through plastic substrates, a PPpX intermediate layer was inserted between FOLEDs and the plastic substrates. As the concentration of C-H bonding in the PPpX film deposited at 25 deg. C was increased, PPpX films showed increased transmittance. Surface morphologies of polyethylene terephthalate (PET) covered with the PPpX intermediate layer were improved compared to PET without PPpX on it. Due to the highly cross-linked network structure in the plasma polymer film, water vapor permeability of PET substrates with the PPpX intermediate layer of 75 nm was decreased compared to PET substrates without PPpX on it. FOLEDs with the PPpX intermediate layer showed improved optical and electrical characteristics as well as lifetimes than FOLEDs without the PPpX intermediate layer

  15. Physicochemical properties and enhanced cellullar responses of biocompatible polymeric scaffolds treated with atmospheric pressure plasma using O{sub 2} gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun-Uk; Park, So-Young; Kang, Yoon-Hee [Department of Nano Fusion Technology, Pusan National University, Busan 609735 (Korea, Republic of); Jeong, Se-Young [Division of Cogni-mechatronics Engineering, Pusan National University, Miryang 627706 (Korea, Republic of); Choi, Sae-Hae; Jahng, Yoon-Young; Chung, Gook-Hyun [Division of Biological Sciences, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Kim, Moon-Bum [Department of Dermatology, School of Medicine, Pusan National University, Busan (Korea, Republic of); Cho, Chae-Ryong, E-mail: crcho@pusan.ac.kr [Department of Nano Fusion Technology, Pusan National University, Busan 609735 (Korea, Republic of)

    2011-04-08

    Biocompatible polymeric scaffolds were fabricated by mixing 5 wt.% poly({epsilon}-caprolactone) (P) with 4 wt.% gelatin (G) and 1.6 wt.% Dulbecco's modified Eagle's medium containing 10% fetal bovine serum (D). These PGD scaffolds were also treated with atmospheric pressure (AP) plasma using O{sub 2} reactive gas (to create O-PGD scaffolds). The physicochemical and mechanical properties of the PGD scaffolds were characterized by in vitro biodegradability tests, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, contact angle measurements, and tensile strength measurements. The wettability and hydrophilic properties of the scaffold surface were improved remarkably by adding G and D to P, and by subsequent oxygen-assisted AP plasma treatment. An MTT assay, a cell attachment efficiency assay, scanning electron microscopy, and confocal microscopy revealed that Chinese Hamster Ovary (CHO)-K1 cells exhibited higher cell attachment and viability on the PGD and O-PGD scaffolds than on the P and PG scaffolds. Furthermore, the long-term viability of the CHO cells on the PGD and O-PGD scaffolds without exchanging the cell culture media was significantly improved compared to their viability on the P and PG scaffolds. Overall, the PGD and O-PGD scaffolds are expected to be useful as cell growth supporting biomaterials in tissue engineering.

  16. Study of the adhesive properties versus stability/aging of hernia repair meshes after deposition of RF activated plasma polymerized acrylic acid coating

    International Nuclear Information System (INIS)

    Rivolo, Paola; Nisticò, Roberto; Barone, Fabrizio; Faga, Maria Giulia; Duraccio, Donatella; Martorana, Selanna; Ricciardi, Serena; Magnacca, Giuliana

    2016-01-01

    In order to confer adhesive properties to commercial polypropylene (PP) meshes, a surface plasma-induced deposition of poly-(acrylic acid) (PPAA) is performed. Once biomaterials were functionalized, different post-deposition treatments (i.e. water washing and/or thermal treatments) were investigated with the aim of monitoring the coating degradation (and therefore the loss of adhesion) after 3 months of aging in both humid/oxidant (air) and inert (nitrogen) atmospheres. A wide physicochemical characterization was carried out in order to evaluate the functionalization effectiveness and the adhesive coating homogeneity by means of static water drop shape analysis and several spectroscopies (namely, FTIR, UV–Visible and X-ray Photoemission Spectroscopy). The modification of the adhesion properties after post-deposition treatments as well as aging under different storage atmospheres were investigated by means of Atomic Force Microscopy (AFM) used in Force/Distance (F/D) mode. This technique confirms itself as a powerful tool for unveiling the surface adhesion capacity as well as the homogeneity of the functional coatings along the fibers. Results obtained evidenced that post-deposition treatments are mandatory in order to remove all oligomers produced during the plasma-treatment, whereas aging tests evidenced that these devices can be simply stored in presence of air for at least three months without a meaningful degradation of the original properties. - Highlights: • Plasma polymerized surface functionalization of hernia-repair meshes was used to confer adhesive properties. • The stability of the adhesive coating was verified under different post-deposition conditions. • The use of AFM in F/D mode was selected to monitor the coating degradation.

  17. Study of the adhesive properties versus stability/aging of hernia repair meshes after deposition of RF activated plasma polymerized acrylic acid coating

    Energy Technology Data Exchange (ETDEWEB)

    Rivolo, Paola [Politecnico di Torino, Department of Applied Science and Technology, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Nisticò, Roberto, E-mail: roberto.nistico@unito.it [University of Torino, Department of Chemistry and NIS Centre, Via P. Giuria 7, 10125 Torino (Italy); Barone, Fabrizio [University of Torino, Department of Chemistry and NIS Centre, Via P. Giuria 7, 10125 Torino (Italy); Faga, Maria Giulia; Duraccio, Donatella [CNR-IMAMOTER, Strada delle Cacce 73, 10135 Torino (Italy); Martorana, Selanna [Herniamesh S.r.l., Via F.lli Meliga 1/C, 10034 Chivasso (Italy); Ricciardi, Serena [Politecnico di Torino, Department of Applied Science and Technology, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Magnacca, Giuliana [University of Torino, Department of Chemistry and NIS Centre, Via P. Giuria 7, 10125 Torino (Italy)

    2016-08-01

    In order to confer adhesive properties to commercial polypropylene (PP) meshes, a surface plasma-induced deposition of poly-(acrylic acid) (PPAA) is performed. Once biomaterials were functionalized, different post-deposition treatments (i.e. water washing and/or thermal treatments) were investigated with the aim of monitoring the coating degradation (and therefore the loss of adhesion) after 3 months of aging in both humid/oxidant (air) and inert (nitrogen) atmospheres. A wide physicochemical characterization was carried out in order to evaluate the functionalization effectiveness and the adhesive coating homogeneity by means of static water drop shape analysis and several spectroscopies (namely, FTIR, UV–Visible and X-ray Photoemission Spectroscopy). The modification of the adhesion properties after post-deposition treatments as well as aging under different storage atmospheres were investigated by means of Atomic Force Microscopy (AFM) used in Force/Distance (F/D) mode. This technique confirms itself as a powerful tool for unveiling the surface adhesion capacity as well as the homogeneity of the functional coatings along the fibers. Results obtained evidenced that post-deposition treatments are mandatory in order to remove all oligomers produced during the plasma-treatment, whereas aging tests evidenced that these devices can be simply stored in presence of air for at least three months without a meaningful degradation of the original properties. - Highlights: • Plasma polymerized surface functionalization of hernia-repair meshes was used to confer adhesive properties. • The stability of the adhesive coating was verified under different post-deposition conditions. • The use of AFM in F/D mode was selected to monitor the coating degradation.

  18. 3D Plasma Nanotextured® Polymeric Surfaces for Protein or Antibody Arrays, and Biomolecule and Cell Patterning.

    Science.gov (United States)

    Tsougeni, Katerina; Ellinas, Kosmas; Koukouvinos, George; Petrou, Panagiota S; Tserepi, Angeliki; Kakabakos, Sotirios E; Gogolides, Evangelos

    2018-01-01

    Plasma micro-nanotexturing is a generic technology for topographical and chemical modification of surfaces and their implementation in microfluidics and microarrays. Nanotextured surfaces with desirable chemical functionality (and wetting behavior) have shown excellent biomolecule immobilization and cell adhesion. Specifically, nanotextured hydrophilic areas show (a) strong binding of biomolecules and (b) strong adhesion of cells, while nanotextured superhydrophobic areas show null adsorption of (a) proteins and (b) cells. Here we describe the protocols for (a) biomolecule adsorption control on nanotextured surfaces for microarray fabrication and (b) cell adhesion on such surfaces. 3D plasma nanotextured® substrates are commercialized through Nanoplasmas private company, a spin-off of the National Centre for Scientific Research Demokritos.

  19. Spectroscopic study of monitoring the kinetics of radical copolymerization of di(ethylene glycol) bis(allylcarbonate) and 2-naphthylmethacrylate

    Science.gov (United States)

    Barashkov, N. N.; Novikova, T. S.; Sakhno, T. V.; Bulgakova, L. M.

    1996-03-01

    The results of fluorescence monitoring in the radical copolymerization of di(ethylene glycol) bis(allylcarbonate) and 2-naphthylmethacrylate are discussed. Our studies suggest that data based on measurement of the intensity of the fluorescence band at 345 nm during copolymerization are in good agreement with the data obtained by the traditional dilatometric method.

  20. Characterization of Plasma-Polymerized 4-vinyl pyridine on Poly(Ethylene Terephthalate) film for anti-microbial properties

    DEFF Research Database (Denmark)

    Jiang, Juan; Winther-Jensen, Bjørn; Kjær, Erik Michael

    2005-01-01

    As an efficient way to create an anti-bacterial function on polymer surfaces, we have used plasma polymerisation to create a poly-4-vinyl-pyridine coating on the surface of a common polymer, PET, a polymerisation process that we have shown also works well on several other polymers. We have found....... The mechanical strength of the bond between the substrate and the surface layer has been tested by several methods, and the antibacterial effect of the surface layer with and without silver nano particles has been estimated by measuring electrical resistance as a function of time. The bacteria investigated were...

  1. The mechanism of electrodeposition of bismuth sulfide and cadmium sulfide from dimethylsulfoxide and diethylene glycol solution

    International Nuclear Information System (INIS)

    Gilbert, C.M.; Baranski, A.S.; Fawcett, W.R.

    1985-01-01

    The kinetics of the electrodeposition of Bi 2 S 3 on an electrode covered with a coherent layer of Bi 2 S 3 was examined by analysis of the Tafel plots for different solution compositions and at different temperatures in two nonaqueous solvents, dimethylsulfoxide (DMSO) and diethylene glycol (DEG). The results were compared with those obtained for the electrodeposition of CdS on CdS under similar conditions. In both cases, it was found that the rate-determining step was an irreversible electron transfer. The rate of the reaction was independent of the metal ion concentration, but electrochemical orders with respect to S 8 of 0.7 in DMSO and 1.0 in DEG were found. Several mechanisms explaining these results are proposed and discussed

  2. Performance of diethylene glycol-based particle counters in the sub-3 nm size range

    CERN Document Server

    Wimmer, D; Franchin, A; Kangasluoma, J; Kreissl, F; Kürten, A; Kupc, A; Metzger, A; Mikkilä, J; Petäjä, J; Riccobono, F; Vanhanen, J; Kulmala, M; Curtius, J

    2013-01-01

    When studying new particle formation, the uncertainty in determining the "true" nucleation rate is considerably reduced when using condensation particle counters (CPCs) capable of measuring concentrations of aerosol particles at sizes close to or even at the critical cluster size (1–2 nm). Recently, CPCs able to reliably detect particles below 2 nm in size and even close to 1 nm became available. Using these instruments, the corrections needed for calculating nucleation rates are substantially reduced compared to scaling the observed formation rate to the nucleation rate at the critical cluster size. However, this improved instrumentation requires a careful characterization of their cut-off size and the shape of the detection efficiency curve because relatively small shifts in the cut-off size can translate into larger relative errors when measuring particles close to the cut-off size. Here we describe the development of two continuous-flow CPCs using diethylene glycol (DEG) as the working fluid. The desig...

  3. Immobilization of Gibberella fujikuroi cells with carriers modified by radiation polymerization

    International Nuclear Information System (INIS)

    Lu Zhaoxin; Xie Zhongchuan; Wei Qijiang

    1994-01-01

    Gibberella fujikuroi cells were immobilized on modified carriers (gauze) by using the radiation polymerization technique. The mycelium was firmly adhered to the surface of fibril covered with hydrophobic polymer, poly (diethylene glycol dimethyl acrylate) and hydrophobic-hydrophilic copolymer poly (diethylene glycol dimethyl acrylate-sodium acrylate), but it was not immobilized onto the polyethylene net, which has a similar network structure to that of the modified carrier. The weight of immobilized cells was affected by covered polymer. Gibberellic acid productivity in immobilized cells was similar to that of free cells, and the immobilized cells was of good stability. A optimum culture condition for gibberellic acid production was at pH 5.5 and under 20 ∼ 30 degree C

  4. Immobilization of enzymes by radiation-induced polymerization of glass-forming monomers

    International Nuclear Information System (INIS)

    Yoshida, M.; Kumakura, M.; Kaetsu, I.

    1979-01-01

    The effect of cooling rate of a monomeric system on the porosity and activity of an immobilized enzyme prepared by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperatures has been studied. Slow cooling gave the same effect on porosity of the polymer as decreasing the monomer concentration. A glass-forming solvent such as diethylene glycol was added to water to study the effect of the supercooling tendency of the solvent. Addition of diethylene glycol decreased porosity and also enzymic activity. Water was replaced by the miscible solvent p-dioxane and the immiscible solvent n-decane in order to clarify the effect of solvent. p-Dioxane had a similar effect to water on the relation between the monomer concentration, porosity and activity. On the other hand, polymer prepared from the system containing n-decane showed different immobilization properties owing to the presence of independent pores in the matrix. (author)

  5. Equilibrium and kinetics study on hexavalent chromium adsorption onto diethylene triamine grafted glycidyl methacrylate based copolymers

    International Nuclear Information System (INIS)

    Maksin, Danijela D.; Nastasović, Aleksandra B.; Milutinović-Nikolić, Aleksandra D.; Suručić, Ljiljana T.; Sandić, Zvjezdana P.; Hercigonja, Radmila V.; Onjia, Antonije E.

    2012-01-01

    Highlights: ► Methacrylate based copolymers grafted with diethylene triamine as Cr(VI) sorbents. ► Chemisorption and pore diffusion are characteristics of this sorption system. ► Langmuir isotherm provided best fit and maximum adsorption capacity was 143 mg g −1 . ► Cr(VI) sorption onto amino-functionalized copolymer was endothermic and spontaneous. ► A simple, efficient and cost-effective hexavalent chromium removal method. - Abstract: Two porous and one non-porous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) [abbreviated PGME] were prepared by suspension copolymerization and functionalized with diethylene triamine [abbreviated PGME-deta]. Samples were characterized by elemental analysis, mercury porosimetry, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and transmission electron microscopy. Kinetics of Cr(VI) sorption by PGME-deta were investigated in batch static experiments, in the temperature range 25–70 °C. Sorption was rapid, with the uptake capacity higher than 80% after 30 min. Sorption behavior and rate-controlling mechanisms were analyzed using five kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion and Bangham model). Kinetic studies showed that Cr(VI) adsorption adhered to the pseudo-second-order model, with definite influence of pore diffusion. Equilibrium data was tested with Langmuir, Freundlich and Tempkin adsorption isotherm models. Langmuir model was the most suitable indicating homogeneous distribution of active sites on PGME-deta and monolayer sorption. The maximum adsorption capacity from the Langmuir model, Q max , at pH 1.8 and 25 °C was 143 mg g −1 for PGME2-deta (sample with the highest amino group concentration) while at 70 °C Q max reached the high value of 198 mg g −1 . Thermodynamic parameters revealed spontaneous and endothermic nature of Cr(VI) adsorption onto PGME-deta.

  6. Elektroaktive polymerer

    DEFF Research Database (Denmark)

    West, K.

    Traditionelt tænker vi på polymerer (plastik) som elektrisk isolerende materialer - det som er udenpå ledningerne. I dag kender vi imidlertid også polymerer med intrinsisk elektrisk ledningsevne, og plast er på vej ind i anvendelser, der tidligereudelukkende var baseret på metaller og uorganiske...... halvledere. Hertil kommer, at en del af de ledende polymerer kan stimuleres til at skifte mellem en ledende og en halvledende tilstand, hvorved de ændret både form og farve. I foredraget gives der enrække eksempler på anvendelse af polymerer som elektriske komponenter - rækkende fra polymer elektronik over...

  7. From superamphiphobic to amphiphilic polymeric surfaces with ordered hierarchical roughness fabricated with colloidal lithography and plasma nanotexturing.

    Science.gov (United States)

    Ellinas, K; Tserepi, A; Gogolides, E

    2011-04-05

    Ordered, hierarchical (triple-scale), superhydrophobic, oleophobic, superoleophobic, and amphiphilic surfaces on poly(methyl methacrylate) PMMA polymer substrates are fabricated using polystyrene (PS) microparticle colloidal lithography, followed by oxygen plasma etching-nanotexturing (for amphiphilic surfaces) and optional subsequent fluorocarbon plasma deposition (for amphiphobic surfaces). The PS colloidal microparticles were assembled by spin-coating. After etching/nanotexturing, the PMMA plates are amphiphilic and exhibit hierarchical (triple-scale) roughness with microscale ordered columns, and dual-scale (hundred nano/ten nano meter) nanoscale texture on the particles (top of the column) and on the etched PMMA surface. The spacing, diameter, height, and reentrant profile of the microcolumns are controlled with the etching process. Following the design requirements for superamphiphobic surfaces, we demonstrate enhancement of both hydrophobicity and oleophobicity as a result of hierarchical (triple-scale) and re-entrant topography. After fluorocarbon film deposition, we demonstrate superhydrophobic surfaces (contact angle for water 168°, compared to 110° for a flat surface), as well as superoleophobic surfaces (153° for diiodomethane, compared to 80° for a flat surface).

  8. Enhanced mechanical properties of low-surface energy thin films by simultaneous plasma polymerization of fluorine and epoxy containing polymers

    Energy Technology Data Exchange (ETDEWEB)

    Karaman, Mustafa, E-mail: karamanm@selcuk.edu.tr [Department of Chemical Engineering, Selçuk University, Konya, 42075 (Turkey); Advanced Technology Research & Application Center, Selçuk University, Konya, 42075 (Turkey); Uçar, Tuba [Department of Chemical Engineering, Selçuk University, Konya, 42075 (Turkey)

    2016-01-30

    Graphical abstract: - Highlights: • Thin films of poly(hexafluorobutyl acrylate-glycidyl methacrylate) can be deposited by PECVD. • The coated surfaces are hydrophobic due to the long fluorinated side chains. • The hydrophobicity of the coating is observed to be stable under harsh conditions. • Film durability is attributed to the mechanical strength of the films due to their epoxide functionality. - Abstract: Thin films of poly(2,2,3,4,4,4 hexafluorobutyl acrylate-glycidyl methacrylate) (P(HFBA-GMA) were deposited on different surfaces using an inductively coupled RF plasma reactor. Fluorinated polymer was used to impart hydrophobicity, whereas epoxy polymer was used for improved durability. The deposition at a low plasma power and temperature was suitable for the functionalization of fragile surfaces such as textile fabrics. The coated rough textile surfaces were found to be superhydrophobic with water contact angles greater than 150° due to the high retention of long fluorinated side chains. The hydrophobicity of the surfaces was observed to be stable after many exposures to ultrasonification tests, which is attributed to the mechanical durability of the films due to their epoxide functionality. FTIR and XPS analyses of the deposited films confirmed that the epoxide functionality of the polymers increased with increasing glycidyl methacrylate fraction in the reactor inlet. The modulus and hardness values of the films also increase with increasing epoxide functionality.

  9. Hydrophobicity attainment and wear resistance enhancement on glass substrates by atmospheric plasma-polymerization of mixtures of an aminosilane and a fluorocarbon

    Energy Technology Data Exchange (ETDEWEB)

    Múgica-Vidal, Rodolfo, E-mail: rodolfo.mugica@alum.unirioja.es [Department of Mechanical Engineering, University of La Rioja, c/ Luis de Ulloa 20, 26004, Logroño, La Rioja (Spain); Alba-Elías, Fernando, E-mail: fernando.alba@unirioja.es [Department of Mechanical Engineering, University of La Rioja, c/ Luis de Ulloa 20, 26004, Logroño, La Rioja (Spain); Sainz-García, Elisa, E-mail: elisa.sainzg@unirioja.es [Department of Mechanical Engineering, University of La Rioja, c/ Luis de Ulloa 20, 26004, Logroño, La Rioja (Spain); Pantoja-Ruiz, Mariola, E-mail: mpruiz@ing.uc3m.es [Materials Science and Engineering Department, IAAB, Materials Performance Group, University Carlos III of Madrid, Av. Universidad 30, 28911, Leganés, Madrid (Spain)

    2015-08-30

    Graphical abstract: - Highlights: • APTES and PFH were used to coat glass by non-thermal atmospheric jet plasma. • A mixture of 75% of APTES and 25% PFH produced the best sample of this work. • Hydrophobicity was achieved by changes in surface morphology and chemistry. • Wear resistance was enhanced by the formation of siloxane groups. - Abstract: Mixtures of different proportions of two liquid precursors were subjected to plasma-polymerization by a non-thermal atmospheric jet plasma system in a search for a coating that achieves a hydrophobic character on a glass substrate and enhances its wear resistance. 1-Perfluorohexene (PFH) was chosen as a low-surface-energy precursor to promote a hydrophobic character. Aminopropyltriethoxysilane (APTES) was chosen for its contribution to the improvement of wear resistance by the formation of siloxane bonds. The objective of this work was to determine which of the precursors’ mixtures that were tested provides the coating with the most balanced enhancement of both hydrophobicity and wear resistance, given that coatings deposited with fluorocarbon-based precursors such as PFH are usually low in resistance to wear and coatings deposited with APTES are generally hydrophilic. The coatings obtained were analyzed by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infra-Red (FTIR) spectroscopy, X-ray Photoelectron Spectroscopy (XPS), static Water Contact Angle (WCA) measurements, tribological ball-on-disc tests and contact profilometry. A relationship between the achievement of a hydrophobic character and the modifications to roughness and surface morphology and the incorporation of fluorocarbon groups in the surface chemistry was observed. Also, it was seen that the wear resistance was influenced by the SiOSi content of the coatings. In turn, the SiOSi content appears to be directly related to the percentage of APTES used in the mixture of precursors. The best conjunction of

  10. Promotion of tribological and hydrophobic properties of a coating on TPE substrates by atmospheric plasma-polymerization

    Science.gov (United States)

    Sainz-García, Elisa; Alba-Elías, Fernando; Múgica-Vidal, Rodolfo; Pantoja-Ruiz, Mariola

    2016-05-01

    Thermoplastic elastomers (TPE) are used in the automotive sealing industry with the objective of producing anti-friction and hydrophobic components. At present, the anti-friction property is achieved by the electrostatic flocking, which sometimes produces an irregular coating. Therefore, this paper's objective is the promotion of adhesion of an anti-friction (based on the silane aminopropyltriethoxysilane-APTES-) and hydrophobic (based on the fluorinated precursor 1-perfluorohexene-PFH-) coating by the adhesion promoter, APTES. Different mixtures of APTES and PFH have been applied to a TPE substrate by an Atmospheric Pressure Plasma Jet (APPJ) system with Dielectric Barrier Discharge (DBD) in order to determine the optimal mixture of precursors. The main difficulty in this work lies in the hydrophilic character of APTES and the low adhesion of the fluorinated coatings. The sample coated with a mixture of 50% APTES and 50% PFH (A50P50) was found to be the best one to satisfy both properties at the same time, despite not having the highest dynamic water contact angle (WCA) or the lowest friction coefficient.

  11. Composite film fabricated on biomedical material with corona streamer plasma processing to mitigate bacterial adhesion

    Science.gov (United States)

    Alhamarneh, Ibrahim; Pedrow, Patrick; Eskhan, Asma; Abu-Lail, Nehal

    2011-10-01

    Composite films might control bacterial adhesion and concomitant biofouling that afflicts biomedical materials. Different size molecules of polyethylene glycol (PEG) with nominal molecular weights 600, 2000, and 20000 g/mol were used to synthesize composite films with plasma processing and dip-coating procedures on surgical-grade 316L stainless steel. Before dip-coating, the substrate was pre-coated with plasma-polymerized di(ethylene glycol) vinyl ether (pp-EO2V) in an atmospheric pressure corona streamer plasma reactor. The PEG dip-coating step followed immediately in the same chamber due to the finite lifetime of radicals associated with freshly deposited pp-EO2V. Morphology of the composite film was investigated with an ESEM. FTIR confirmed incorporation of pp-EO2V and PEG species into the composite film. More investigations on the composite film were conducted by XPS measurements. Adhesion of the composite film was evaluated with a standard peel-off test. Stability of the composite film in buffer solution was evaluated by AFM. AFM was also used to measure the film roughness and thickness. Polar and non-polar contact angle measurements were included.

  12. In situ synthesis of silver nanoparticles on the cotton fabrics modified by plasma induced vapor phase graft polymerization of acrylic acid for durable multifunction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C.X., E-mail: cxwang@mail.dhu.edu.cn [College of Textiles and Clothing, Yancheng Institute of Technology, Jiangsu, 224003 (China); Collaborative Innovation Center for Ecological Building, Materials and Environmental Protection Equipments, Jiangsu, 224051 (China); Laboratory for Advanced Technology in Environmental Protection, Jiangsu, 224051 (China); School of Textile and Clothing, Nantong University, Jiangsu, 226019 (China); Ren, Y. [School of Textile and Clothing, Nantong University, Jiangsu, 226019 (China); Lv, J.C.; Zhou, Q.Q.; Ma, Z.P.; Qi, Z.M.; Chen, J.Y.; Liu, G.L.; Gao, D.W. [College of Textiles and Clothing, Yancheng Institute of Technology, Jiangsu, 224003 (China); Lu, Z.Q. [College of Textiles and Clothing, Yancheng Institute of Technology, Jiangsu, 224003 (China); Collaborative Innovation Center for Ecological Building, Materials and Environmental Protection Equipments, Jiangsu, 224051 (China); Laboratory for Advanced Technology in Environmental Protection, Jiangsu, 224051 (China); Zhang, W. [College of Textiles and Clothing, Yancheng Institute of Technology, Jiangsu, 224003 (China); Jin, L.M. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201204 (China)

    2017-02-28

    Highlights: • A new means for multifunctional cotton fabrics by PIVPGP of AA and AgNPs synthesis. • Surface modification by PIVPGP of AA had a positive effect on AgNPs loading. • Antibacterial, self-cleaning and thermal stability were greatly improved. • AgNP loaded cotton fabric exhibited excellent laundering durability. • Mechanism of AgNPs in situ synthesis on cotton fabrics by PIVPGP of AA was proposed. - Abstract: A practical and ecological method for preparing the multifunctional cotton fabrics with excellent laundering durability was explored. Cotton fabrics were modified by plasma induced vapor phase graft polymerization (PIVPGP) of acrylic acid (AA) and subsequently silver nanoparticles (AgNPs) were in situ synthesized on the treated cotton fabrics. The AgNP loaded cotton fabrics were characterized by scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), antibacterial activity, self-cleaning activity, thermal stability and laundering durability, respectively. SEM observation and EDX, XPS and XRD analysis demonstrated the much more AgNPs deposition on the cotton fabrics modified by PIVPGP of AA. The AgNP loaded cotton fabrics also exhibited better antibacterial activity, self-cleaning activity, thermal stability and laundering durability. It was concluded that the surface modification of the cotton fabrics by PIVPGP of AA could increase the loading efficiency and binding fastness of AgNPs on the treated cotton fabrics, which could fabricate the cotton fabrics with durable multifunction. In addition, the mechanism of in situ synthesis of AgNPs on the cotton fabrics modified by PIVPGP of AA was proposed.

  13. Thermo-responsive wound dressings by grafting chitosan and poly(N-isopropylacrylamide) to plasma-induced graft polymerization modified non-woven fabrics

    International Nuclear Information System (INIS)

    Chen, Jyh-Ping; Kuo, Chang-Yi; Lee, Wen-Li

    2012-01-01

    Highlights: ► Poly(N-isopropylacrylamide) and chitosan were grafted to polypropylene non-wovens. ► An easily stripped off thermo-responsive wound dressing was developed. ► The wound dressing is biocompatible, has antibacterial and wound healing abilities. ► The bigraft non-woven will be a potential wound dressing for biomedical use. - Abstract: To obtain a chitosan wound dressings with temperature-responsive characteristics, polypropylene (PP) non-woven fabric (NWF) was modified by direct current pulsed oxygen plasma-induced grafting polymerization of acrylic acid (AAc) to improve hydrophilicity and to introduce carboxylic acid groups. Conjugation of chitosan and poly(N-isopropylacrylamide) (PNIPAAm) followed by using water-soluble carbodiimide as a coupling agent to form a novel bigraft PP-g-chitosan-g-PNIPAAm wound dressing. The amount of chitosan and PNIPAAm grafted to PP-g-chitosan-g-PNIPAAm were 83.0 ± 4.6 μg/cm 2 and 189.5 ± 8.2 μg/cm 2 , respectively. The surface chemical composition and microstructure of the NWF were studied by electron spectroscopy for chemical analysis (ESCA) and scanning electron microscopy (SEM). The linkages between AAc, chitosan, and PNIPAAm were confirmed with the formation of amide bonds. Physical properties of the NWF were characterized and potentials of these NWFs as wound dressings were evaluated using SD rat as the animal model. NWFs contained PNIPAAm were better than those contained only chitosan in wound healing rates and the wound areas covered by PP-g-chitosan-g-PNIPAAm wound dressings healed completely in 17 days.

  14. Redução da hidrofilicidade de filmes biodegradáveis à base de amido por meio de polimerização por plasma Reduction of hydrophilicity of biodegradable starch-based films by plasma polymerization

    Directory of Open Access Journals (Sweden)

    Rossana M. S. M. Thiré

    2004-03-01

    Full Text Available Devido ao baixo custo de produção e excelente biodegradabilidade, o amido constitui-se em matéria-prima promissora para a produção de plásticos biodegradáveis. No entanto, a grande hidrofilicidade dos filmes à base de amido representa uma séria limitação tecnológica à sua comercialização, uma vez que as propriedades dos filmes são afetadas pela variação da umidade relativa do ar durante a sua estocagem ou o seu uso. Neste trabalho, filmes de amido termoplástico foram recobertos com uma fina camada protetora polimérica gerada por intermédio da tecnologia de plasma frio. 1-Buteno e 1,3-butadieno foram utilizados como monômeros para a polimerização por plasma. Os filmes recobertos apresentaram uma redução de até 80% na absorção de água e aumento do ângulo de contato em relação à água. Estes resultados indicaram uma redução significativa na natureza hidrofílica do material à base de amido após o recobrimento.Due to low cost and excellent biodegradability, the use of starch as a raw material for bioplastic production is growing in interest. However, the properties of starch-based materials are affected by relative humidity during their use and storage due to their hydrophilic character. In this work, thermoplastic cornstarch films were coated by cold plasma technology with a protective thin layer in order to reduce water sensitivity. 1-Butene and 1,3-butadiene were used as monomers for plasma polymerization. Coated films presented a reduction of water absorption up to 80% an increase in contact angle related to water. These results indicated that the coating process reduced significantly the hydrophilic nature of the starch-based materials.

  15. Preparation and characterization of diethylene glycol bis(2-aminophenyl) ether-modified glassy carbon electrode

    International Nuclear Information System (INIS)

    Isbir, Aybueke A.; Solak, Ali Osman; Ustuendag, Zafer; Bilge, Selen; Kilic, Zeynel

    2006-01-01

    Diethylene glycol bis(2-aminophenyl) ether (DGAE) diazonium salt was covalently electrografted on a glassy carbon (GC) surface and behavior of this novel surface was investigated. Synthesis of DGAE diazonium salt (DGAE-DAS) and in situ modification of GC electrode were performed in aqueous media containing NaNO 2 , keeping the temperature below +4 deg. C. For the characterization of the modified electrode surface by cyclic voltammetry, dopamine (DA) was used to prove the attachment of the DGAE-DAS on the GC surface. Raman spectroscopy and electrochemical impedance spectroscopy (EIS) were used to observe the molecular bound properties of the adsorbates at the DGAE-modified GC surface (GC-DGAE). The EIS results were analyzed using the Randles equivalent circuit. The charge transfer resistance on bare GC and the modified surface were calculated using the model equivalent circuit for the ferrocene redox system. Surface coverage was found as 0.4 showing the presence of high pinhole and defects in the modified electrode. The rate constant of electron transfer through the monolayer was calculated for ferrocene. Working potential range and the stability of the DGAE-modified GC electrode was also determined

  16. Preparation and characterization of diethylene glycol bis(2-aminophenyl) ether-modified glassy carbon electrode

    Energy Technology Data Exchange (ETDEWEB)

    Isbir, Aybueke A. [Ankara University, Faculty of Science, Department of Chemistry, 06100 Tandogan, Ankara (Turkey); Solak, Ali Osman [Ankara University, Faculty of Science, Department of Chemistry, 06100 Tandogan, Ankara (Turkey)]. E-mail: osolak@science.ankara.edu.tr; Ustuendag, Zafer [Ankara University, Faculty of Science, Department of Chemistry, 06100 Tandogan, Ankara (Turkey); Bilge, Selen [Ankara University, Faculty of Science, Department of Chemistry, 06100 Tandogan, Ankara (Turkey); Kilic, Zeynel [Ankara University, Faculty of Science, Department of Chemistry, 06100 Tandogan, Ankara (Turkey)

    2006-07-28

    Diethylene glycol bis(2-aminophenyl) ether (DGAE) diazonium salt was covalently electrografted on a glassy carbon (GC) surface and behavior of this novel surface was investigated. Synthesis of DGAE diazonium salt (DGAE-DAS) and in situ modification of GC electrode were performed in aqueous media containing NaNO{sub 2}, keeping the temperature below +4 deg. C. For the characterization of the modified electrode surface by cyclic voltammetry, dopamine (DA) was used to prove the attachment of the DGAE-DAS on the GC surface. Raman spectroscopy and electrochemical impedance spectroscopy (EIS) were used to observe the molecular bound properties of the adsorbates at the DGAE-modified GC surface (GC-DGAE). The EIS results were analyzed using the Randles equivalent circuit. The charge transfer resistance on bare GC and the modified surface were calculated using the model equivalent circuit for the ferrocene redox system. Surface coverage was found as 0.4 showing the presence of high pinhole and defects in the modified electrode. The rate constant of electron transfer through the monolayer was calculated for ferrocene. Working potential range and the stability of the DGAE-modified GC electrode was also determined.

  17. Food and pharmaceuticals. Lessons learned from global contaminations with melamine/cyanuric acid and diethylene glycol.

    Science.gov (United States)

    Brown, C A; Brown, S A

    2010-01-01

    Recently, contamination of pharmaceuticals with diethylene glycol (DEG) and food with melamine and cyanuric acid has demonstrated the impact of globalization on drug and food safety. By examining the details of these outbreaks, some important lessons can be learned. Toxicoses from contaminated food and drugs are often identified only when large numbers of people or animals are affected and numerous deaths result. Populations most at risk are those repeatedly exposed to a single product. Toxicoses may be complex, involving synergism among relatively nontoxic co-contaminants. Although some contamination may occur inadvertently, practices of deliberate contamination of food and drug ingredients may be widespread but escape detection in poorly regulated markets. If this deliberate contamination is motivated by personal financial gain, it is likely to recur and be concealed. The contaminated raw material produced in a poorly regulated market may cross national boundaries and be used in manufacturing processes for numerous products, sometimes in more well-regulated markets. Once in the production chain, contaminated raw materials may be widely disseminated. It is not clear that regulatory organizations have the capacity to identify significant contaminations despite their best efforts. The veterinary and medical communities, in cooperation with regulatory agencies, should develop cooperative programs designed to detect and limit these global outbreaks. Although addressing regional or national outbreaks remains an important role for regulatory agencies, the veterinary and medical communities must develop proactive global approaches to this global problem.

  18. Glycidyl methacrylate macroporous copolymer grafted with diethylene triamine as sorbent for Reactive Black 5

    Directory of Open Access Journals (Sweden)

    Sandić Zvjezdana P.

    2014-01-01

    Full Text Available In this paper, macroporous glycidyl methacrylate and ethylene glycol dimethacrylate copolymer functionalized with diethylene triamine [PGME-deta], was evaluated as Reactive Black 5 (RB5 sorbent. Batch RB5 removal from aqueous solution by PGME-deta was investigated by varying pH, contact time, sorbent dosage, initial dye concentration and temperature. The sorption is pH sensitive having maximum at pH 2 (dye removal of 85%, decreasing with the increase of pH (dye removal of 24% at pH=11 after 60 min. Sorption kinetics was fitted to chemical-reaction and particle-diffusion models (pseudo-first-order, pseudo-second-order, intraparticle diffusion and Mckay models. The pseudo-second-order kinetic model accurately predicted the RB5 amount sorbed under all investigated operating conditions, while the intraparticle diffusion was the dominant rate-limiting mechanism. The diffusion mechanism was more prevalent with the decrease in temperature and the increase in concentration. The isotherm data was best fitted with the Langmuir model, indicating homogeneous distribution of active sites on PGME-deta and monolayer sorption, with the maximum sorption capacity of 353 mg g-1. The calculated sorption rates improved with increasing temperature and an activation energy close to 40 kJ mol-1 was determined, suggesting that chemisorption was also rate-controlling. [Projekat Ministarstva nauke Republike Srbije, br. III 43009, br. TR 37021 i br. III 45001

  19. Transient renal impairment in rats after oral exposure to diethylene glycol.

    Science.gov (United States)

    Freundt, K J; Weis, N

    1989-10-01

    Volume, specific gravity, creatinine, lactate dehydrogenase (LDH), leucine aminopeptidase (LAP), beta-galactosidase (GAL), leucocytes, erythrocytes, nitrite, protein (albumin), glucose, ketone, urobilinogen, bilirubin and pH were estimated in urine of rats after single (by gavage) or repeated (via drinking water) oral administration of diethylene glycol (DEG). Following single or repetitive doses (daily over 90 days) of 0.2 g DEG kg-1 body weight, no change in renal function was observed (no effect level). In urine of rats treated once with 0.7 g DEG kg-1 body weight, LDH activity was significantly enhanced one day after treatment. A single dose of 2.0 g DEG kg-1 body weight resulted in an additional rise in urinary GAL activity two days after treatment, a significant rise of urinary volume and a decrease in creatinine concentration and pH on the first day. One day following a single dose of 8.0 g DEG kg-1 body weight, in addition to the changes mentioned before, LAP activity was significantly elevated and the specific gravity decreased. However, in all experiments the wet weight of the kidneys remained normal as compared to controls. The results thus show dose-dependent changes in several renal parameters, indicating a slight-to-moderate and reversible renal impairment.

  20. Effects of diethylene glycol butyl ether and butoxyethoxyacetic acid on rat and human erythrocytes.

    Science.gov (United States)

    Udden, M M

    2005-03-28

    The toxicity of diethylene glycol butyl ether (DGBE), and its principal metabolite, butoxyethoxyacetic acid (BEAA), were assessed in vitro for rat and human red blood cells. Rat erythrocytes showed evidence of mild hemolysis when exposed to BEAA at concentrations of 5 or 10 mM for 4 h. BEAA treated rat red blood cells also showed evidence of sub-hemolytic damage: increased spherocytosis, a shift in distribution of cell size to larger cells, a significant increase in mean cellular volume, and a decrease in cellular deformability. However, DGBE had no effect on rat red blood cell morphology, cell size, hemolysis or deformability. There was no hemolysis when human red blood cells were exposed to DGBE or BEAA at the same concentrations. No changes in mean cellular volume, distribution of cell size, or morphologic appearance of human red blood cells were observed. No evidence for decreased deformability of human red blood cells exposed to DGBE or BEAA was found. In conclusion, BEAA has weak hemolytic activity and sub-hemolytic effects in vitro on rat erythrocytes, which is consistent with the finding of mild hemolysis when the parent compound DGBE is administered to rats by gavage. The absence of hemolysis or sub-hemolytic damage when human red blood cells were exposed to BEAA or DGBE in vitro indicates that it is unlikely that hemolysis will occur as a result of human exposure to DGBE.

  1. Diethylene glycol monoethyl ether (Transcutol) displays antiproliferative properties alone and in combination with xanthines.

    Science.gov (United States)

    Levi-Schaffer, F; Dayan, N; Touitou, E

    1996-01-01

    In the present study we have investigated the effects of diethylene glycol monoethyl ether (Transcutol) in combination with theophylline, caffeine and dyphylline and alone on 3T3 mouse fibroblast proliferation. These three xanthines (1-0.01 mM) inhibited fibroblast proliferation by themselves. Enhancement of the effect was detected by addition of 1 and 0.1 mM Transcutol. Transcutol alone also displayed a dose-dependent inhibition (2-0.01 mM) of both 3T3 and human normal and psoriatic fibroblasts, although normal human fibroblasts were the least sensitive to Transcutol antiproliferative activity. Transcutol was assessed for its antiproliferative effects on YAC lymphoma and P-815 mastocytoma human cell lines. Transcutol inhibited cell proliferation of both these cell lines, being more effective towards P-815 mastocytoma (at 2 mM it displayed 3.95-fold vs. 2.4-fold inhibition towards YAC lymphoma). In conclusion, we have shown that Transcutol has antiproliferative effects on 3T3 murine, human normal and psoriatic fibroblasts and tumour cell lines. In addition it enhances xanthine antiproliferative effects on 3T3 fibroblasts. Therefore it might be a useful topical drug alone or in combination with xanthines in the treatment of skin hyperproliferative disorders.

  2. Cellular and antitumor activity of a new diethylene glycol benzoporphyrin derivative (lemuteporfin).

    Science.gov (United States)

    Boch, Ron; Canaan, Alice J; Cho, Angela; Dolphin, David D; Hong, Lina; Jain, Ashok K; North, John R; Richter, Anna M; Smits, Claire; Sternberg, Ethan D

    2006-01-01

    A newly synthesized diethylene glycol functionalized chlorin-type photosensitizer, lemuteporfin, was characterized for use in photodynamic therapy (PDT) in a panel of in vitro and in vivo test systems. The photosensitizer was highly potent, killing cells at low nanomolar concentrations upon exposure to activating light. The cellular uptake of lemuteporfin was rapid, with maximum levels reached within 20 min. Mitogen-activated lymphoid cells accumulated more of the lemuteporfin than their quiescent equivalents, supporting selectivity. Photosensitizer fluorescence in the skin increased rapidly within the first few minutes following intravenous administration to mice, then decreased over the next 24 h. Skin photosensitivity reactions indicated rapid clearance of the photosensitizer. Intravenous doses as low as 1.4 micromol/kg combined with exposure to 50 J/cm2 red light suppressed tumor growth in a mouse model. In conclusion, this new benzoporphyrin was found to be an effective photosensitizer, showing rapid uptake and clearance both in vitro and in vivo. This rapid photosensitization of tumors could be useful in therapies requiring a potent, rapidly accumulating photosensitizer, while minimizing the potential for skin photosensitivity reactions to sunlight following treatment.

  3. Diethylene glycol-induced toxicities show marked threshold dose response in rats

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Greg M., E-mail: Landry.Greg@mayo.edu [Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Dunning, Cody L., E-mail: cdunni@lsuhsc.edu [Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Abreo, Fleurette, E-mail: fabreo@lsuhsc.edu [Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Latimer, Brian, E-mail: blatim@lsuhsc.edu [Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Orchard, Elysse, E-mail: eorcha@lsuhsc.edu [Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Division of Animal Resources, Louisiana State University Health Sciences Center, Shreveport, LA (United States); McMartin, Kenneth E., E-mail: kmcmar@lsuhsc.edu [Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States)

    2015-02-01

    Diethylene glycol (DEG) exposure poses risks to human health because of widespread industrial use and accidental exposures from contaminated products. To enhance the understanding of the mechanistic role of metabolites in DEG toxicity, this study used a dose response paradigm to determine a rat model that would best mimic DEG exposure in humans. Wistar and Fischer-344 (F-344) rats were treated by oral gavage with 0, 2, 5, or 10 g/kg DEG and blood, kidney and liver tissues were collected at 48 h. Both rat strains treated with 10 g/kg DEG had equivalent degrees of metabolic acidosis, renal toxicity (increased BUN and creatinine and cortical necrosis) and liver toxicity (increased serum enzyme levels, centrilobular necrosis and severe glycogen depletion). There was no liver or kidney toxicity at the lower DEG doses (2 and 5 g/kg) regardless of strain, demonstrating a steep threshold dose response. Kidney diglycolic acid (DGA), the presumed nephrotoxic metabolite of DEG, was markedly elevated in both rat strains administered 10 g/kg DEG, but no DGA was present at 2 or 5 g/kg, asserting its necessary role in DEG-induced toxicity. These results indicate that mechanistically in order to produce toxicity, metabolism to and significant target organ accumulation of DGA are required and that both strains would be useful for DEG risk assessments. - Highlights: • DEG produces a steep threshold dose response for kidney injury in rats. • Wistar and F-344 rats do not differ in response to DEG-induced renal injury. • The dose response for renal injury closely mirrors that for renal DGA accumulation. • Results demonstrate the importance of DGA accumulation in producing kidney injury.

  4. In vitro and in vivo genetic toxicology studies with diethylene glycol monohexyl ether.

    Science.gov (United States)

    Ballantyne, B; Vergnes, J S

    2001-01-01

    Diethylene glycol monohexyl ether (DEGHE; CAS no. 112-59-4), an industrial chemical, was investigated for the potential to produce genotoxic effects using three in vitro and two in vivo tests. No mutagenic activity occurred in either the absence or presence of metabolic activation with a Salmonella typhimurium reverse assay using strains TA98, TA100, TA1535, TA1537 and TA1538. In a Chinese hamster ovary (CHO) forward gene mutation test (HGPRT locus) there was an increase in the mutation frequencies, which were relatively small compared with the solvent control values, somewhat inconsistent between duplicate cultures and occurred particularly in the presence of metabolic activation. Linear regression analysis indicated a marginally significant trend for dosage versus mutation frequency, suggesting that DEGHE was weakly positive in this test. A sister chromatid exchange test in CHO cells showed no significant dosage-related effects in the presence or absence of metabolic activation. A peripheral blood micronucleus test in mice by dosing with an intraperitoneal injection of DEGHE did not show any potential for DEGHE to increase the incidence of micronucleated polychromatophilic erythrocytes. In a first femoral bone marrow chromosome aberration test in the rat by peroral dosing, DEGHE did not cause any increase in aberrations for 12-h and 24-h samples with males and females or with females at 48-h sampling. However, with males at 48 h the two lowest doses showed an increased number of aberrations, but not at the high doses. A repeat study in males with a larger number of doses and 24-h and 48-h samples did not replicate this finding. It is concluded that DEGHE may have limited weak mutagenic activity in vitro but is devoid of clastogenic potential. Copyright 2001 John Wiley & Sons, Ltd.

  5. Controlled release of biofunctional substances by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Yoshida, M.; Kumakura, M.; Kaetsu, I.

    1978-01-01

    The controlled release of potassium chloride from flat circular matrices made by radiation-induced polymerization of a glass-forming monomer at low temperatures has been studied. The water-particle phase content formed in a poly(diethylene glycol dimethacrylate) matrix was controlled by the addition of polyethylene glycol 600. The dispersed water-particle phase content in the matrix was estimated directly and by scanning electron microscopic observations. The release of potassium chloride from the matrix increased linearly with the square root of time. The water content of the matrix had an important effect on the release rate which increases roughly in proportion to water content. This effect can be attributed to the apparent increase of the rate of drug diffusion. (author)

  6. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor; Villalobos Vazquez de la Parra, Luis Francisco; Hilke, Roland

    2015-01-01

    microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  7. Density, viscosity, surface tension, and spectroscopic properties for binary system of 1,2-ethanediamine + diethylene glycol

    International Nuclear Information System (INIS)

    Li, Lihua; Zhang, Jianbin; Li, Qiang; Guo, Bo; Zhao, Tianxiang; Sha, Feng

    2014-01-01

    Graphical abstract: Excess property of the binary system 1,2-ethanediamine (EDA) + diethylene glycol (DEG). - Highlights: • Densities and viscosities of EDA + DEG at 298.15–318.150 K were listed. • Thermodynamics data of EDA + DEG at 298.15–318.15 K were calculated. • Surface tension of EDA + DEG at 298.15 K was measured. • Intermolecular interaction of EDA with DEG was discussed. - Abstract: This paper reports density and viscosity data at T = 298.15, 303.15, 308.15, 313.15, and 318.15 K and surface tension data at 298.15 K for the binary system 1,2-ethanediamine (EDA) + diethylene glycol (DEG) as a function of composition under atmospheric pressure. From the experimental density and viscosity data, the excess molar volume and viscosity deviation were calculated, and the results were fitted to a Redlich–Kister equation to obtain the coefficients and to estimate the standard deviations between the experimental and calculated quantities. Based on the kinematic viscosity data, enthalpy of activation for viscous flow, entropy of activation for the viscous flow, and Gibbs energies of activation of viscous flow were calculated. In addition, based on Fourier transform infrared spectra, UV–vis spectra, and electrical conductivity for the system EDA + DEG with various concentrations, intermolecular interaction of EDA with DEG was discussed

  8. Binary and ternary solid-liquid phase equilibrium for the systems formed by succinic acid, urea and diethylene glycol: Determination and modelling

    International Nuclear Information System (INIS)

    Li, Yanxun; Li, Congcong; Han, Shuo; Zhao, Hongkun

    2017-01-01

    Highlights: • Solubility of succinic acid in diethylene glycol was determined. • Solubility of succinic acid + urea + diethylene glycol was determined. • Three ternary phase diagrams were constructed for the ternary system. • The ternary phase diagrams were correlated using NRTL model. - Abstract: In this work, the solid-liquid phase equilibrium for binary system of succinic acid + diethylene glycol at the temperatures ranging from (298.15 to 333.15) K and ternary system of (succinic acid + urea + diethylene glycol) at 298.15 K, 313.15 K and 333.15 K was built by using the isothermal saturation method under atmospheric pressure (101.2 kPa), and the solubilities were determined by a high-performance liquid chromatography. The solid-phases formed in the ternary system of ((succinic acid + urea + diethylene glycol)) were confirmed by Schreinemaker’s method of wet residue, which corresponded to urea, succinic acid, and adduct 2:1 urea-succinic acid (mole ratio). Three isothermal phase diagrams for the ternary system were constructed based on the measured mutual solubility. Each isothermal phase diagram included six crystallization fields, three invariant curves, two invariant points and two co-saturated points. The crystalline region of adduct 2:1 urea-succinic acid is larger than those of the other two solids. The solubility of succinic acid in diethylene glycol was correlated with the modified Apelblat equation, λh equation and NRTL model; and the mutual solubility of the ternary ((succinic acid + urea + diethylene glycol)) system was correlated and calculated by the NRTL model. The interaction parameters’ values of succinic acid-urea were acquired. The value of RMSD was 7.11 × 10 −3 for the ternary system. The calculation results had good agreement with the experiment values. Furthermore, the densities of equilibrium liquid phase were acquired. The phase diagrams and the thermodynamic model of the ternary system could provide the basis for design of

  9. Scintiscanning of the breast with 99Tcsup(m)-diethylene triamine penta-acetic acid - a prospective blind evaluation

    International Nuclear Information System (INIS)

    Cuschieri, A.; Hutchinson, F.; Neill, G.D.S.; Wisbey, M.L.; Wood, R.A.B.; Preece, P.; Clark, J.

    1981-01-01

    In this blind prospective study of breast scintiscanning with 99 Tcsup(m)-diethylene triamine penta-acetic acid (DTPA) in 67 female patients presenting at a primary breast referral clinic, it was observed that this investigation has a high diagnostic accuracy in distinguishing benign from malignant lesions of the breast. The predictive value of the test when positive in establishing the presence of cancer is 94 per cent with a false negative rate of 6 per cent. The predictive value of the test when negative in excluding cancer is 97 per cent with a false positive rate of 3 per cent. Initial studies also indicate the potential value of DTPA breast scintiscanning in delineating the activity of painful benign lesions of the breast. (author)

  10. "Click" i polymerer 2

    DEFF Research Database (Denmark)

    Hvilsted, Søren

    2012-01-01

    "Click"-reaktioner til fremstilling af ledende polymerer med funktionelle håndtag og bipolymermaterialer......"Click"-reaktioner til fremstilling af ledende polymerer med funktionelle håndtag og bipolymermaterialer...

  11. Conducting Polymeric Materials

    DEFF Research Database (Denmark)

    Hvilsted, Søren

    2016-01-01

    The overall objective of this collection is to provide the most recent developments within the various areas of conducting polymeric materials. The conductivity of polymeric materials is caused by electrically charged particles, ions, protons and electrons. Materials in which electrons...

  12. Exploring the polymerization of bioactive nano-cones on the inner surface of an organic tube by an atmospheric pressure pulsed micro-plasma jet

    Science.gov (United States)

    Xu, H. M.; Yu, J. S.; Chen, G. L.; Qiu, X. P.; Hu, W.; Chen, W. X.; Bai, H. Y.

    2015-12-01

    In this paper, the successful deposition of acrylic acid polymer (PAA) nano-cones on the inner surface of a polyvinyl chloride (PVC) tube using an atmospheric pressure pulsed plasma jet (APPJ) with acrylic acid (AA) monomer is presented. Optical emission spectroscopy (OES) measurements indicated that various reactive radicals, such as rad OH and rad O, existed in the plasma jet. Moreover, the pulsed current proportionally increased with the increase in the applied voltage. The strengthened stretching vibration of the carbonyl group (Cdbnd O) at 1700 cm-1, shown in the ATR-FTIR spectra, clearly indicated that the PAA was deposited on the PVC surface. The maximum height of the PAA nano-cones deposited by this method ranged from 150 to 200 nm. FTIR and XPS results confirmed the enhanced exposure of the carboxyl groups on the modified PVC surface, which was considered highly beneficial for successfully immobilizing a high density of biomolecules. The XPS data showed that the carbon ratios of the Csbnd OH/R and COOH/R groups increased from 7.03% and 2.6% to 18.69% and 6.81%, respectively (more than doubled) when an Ar/O2 plasma with AA monomer was applied to treat the inner surface of the PVC tube. Moreover, the enhanced attachment density of MC3T3-E1 bone cells was observed on the PVC inner surface coated with PAA nano-cones.

  13. An optimized two-step derivatization method for analyzing diethylene glycol ozonation products using gas chromatography and mass spectrometry.

    Science.gov (United States)

    Yu, Ran; Duan, Lei; Jiang, Jingkun; Hao, Jiming

    2017-03-01

    The ozonation of hydroxyl compounds (e.g., sugars and alcohols) gives a broad range of products such as alcohols, aldehydes, ketones, and carboxylic acids. This study developed and optimized a two-step derivatization procedure for analyzing polar products of aldehydes and carboxylic acids from the ozonation of diethylene glycol (DEG) in a non-aqueous environment using gas chromatography-mass spectrometry. Experiments based on Central Composite Design with response surface methodology were carried out to evaluate the effects of derivatization variables and their interactions on the analysis. The most desirable derivatization conditions were reported, i.e., oximation was performed at room temperature overnight with the o-(2,3,4,5,6-pentafluorobenzyl) hydroxyl amine to analyte molar ratio of 6, silylation reaction temperature of 70°C, reaction duration of 70min, and N,O-bis(trimethylsilyl)-trifluoroacetamide volume of 12.5μL. The applicability of this optimized procedure was verified by analyzing DEG ozonation products in an ultrafine condensation particle counter simulation system. Copyright © 2016. Published by Elsevier B.V.

  14. Bioaugmentation for treatment of full-scale diethylene glycol monobutyl ether (DGBE) wastewater by Serratia sp. BDG-2.

    Science.gov (United States)

    Chen, Maoxia; Fan, Rong; Zou, Wenhui; Zhou, Houzhen; Tan, Zhouliang; Li, Xudong

    2016-05-15

    A novel bacterial strain BDG-2 was isolated and used to augment the treatment of silicon plate manufacturing wastewater that primarily contains diethylene glycol monobutyl ether (DGBE). BDG-2 was identified as a Serratia sp. Under the optimal conditions of 30 °C, pH 9 and DGBE concentration of 2000 mg L(-1), the bioaugmented system achieved 96.92% COD removal after 39.9h. Laboratory-scale technological matching results indicated that, in a biofilm process with the addition of 100 mg L(-1) ammonia and 5 mg L(-1) total phosphorus (TP), 70.61% COD removal efficiency could be obtained in 46 h. Addition of polyaluminium chloride (PAC) to the reactors during the suspension process enhanced the settleability of the BDG-2 culture. Subsequently, successful start-up and stable operation of a full-scale bioaugmented treatment facilities were accomplished, and the volumetric organic load in the plug-flow aeration tank was 2.17 ± 0.81 kg m(-3) d(-1). The effluent COD of the facilities was stable and always below 100 mg L(-1). Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Activity coefficients at infinite dilution of organic solutes in diethylene glycol and triethylene glycol from gas–liquid chromatography

    International Nuclear Information System (INIS)

    Williams-Wynn, Mark D.; Letcher, Trevor M.; Naidoo, Paramespri; Ramjugernath, Deresh

    2013-01-01

    Highlights: • γ 13 ∞ values reported for 25 organic solutes in the solvents DEG and TEG. • Measurements undertaken using the glc technique at T = (333.2, 348.2, and 363.2) K. • Measurements at elevated temperature possible by pre-saturation of carrier gas. • Comparison of DEG and TEG performance with a number of solvents. -- Abstract: The infinite dilution activity coefficients for 25 hydrocarbon solutes in diethylene glycol (DEG) and triethylene glycol (TEG) were measured using the gas–liquid chromatography technique with pre-saturation of the carrier gas. The hydrocarbon solutes included n-alkanes, alk-1-enes, alk-1-ynes, cycloalkanes, alkylbenzenes and alkanols. At the temperatures at which measurements were conducted, the solvents were volatile, and pre-saturation was considered necessary. The measurements were made at T = (333.2, 348.2 and 363.2) K. Values of the selectivity and capacity relating to DEG and TEG, for two sets of mixtures, which are usually difficult to separate by distillation or solvent extraction, were calculated from the experimental results. The two sets of mixtures were: cyclohexane and benzene; and benzene and methanol. The results obtained in this work were then compared to values for other solvents, at similar temperatures, which were obtained or calculated from literature data

  16. Fixation of radioactive elements on diethylene-glycol-succinate and its use for the determination of gross activity in urine

    International Nuclear Information System (INIS)

    Hafez, M.B.; Nazmy, A.F.; Eldesoky, M.M.

    1977-01-01

    Studies are given to illustrate surface adsorption of 144 Ce, 90 Sr, 232 Th, 235 U, 239 Pu and 241 Am on diethylene-glycol-succinate, DGS. Adsorption of these elements was studied from aqueous and phosphate solutions. A procedure for the determination of gross activity in urine, based on surface adsorption on DGS is described. Groups of nine solutions, in 30 ml 1N HNO 3 , were spiked with the investigated radioactive elements (approximately 5 pCi). The pH of the solutions was adjusted to a range of 0.5 to 10 using ammonia. Each solution was passed through the column and the fixed activity was removed from the column with 50 ml of 4N HCl, followed by two washes with 10 ml of distilled water. The acid solution was evaporated to dryness for alpha- or beta-counting. The percentage fixation was determined by comparison with a standard source of the same spiked element. Adsorption was found to depend on pH, age of the tracer solution, hydrolysis state of the radioelement and the ionic strength of the solution. The adsorption phenomenon which was particularly well observed could be used as a separation stage in a method for the determination of gross activity in urine. Recoveries of about 85% were obtained. (T.G.)

  17. Sync-measurement experimental study of (fluoroethane + dimethylether tetraethylene glycol), (fluoroethane + dimethylether triethylene glycol) and (fluoroethane + dimethylether diethylene glycol) systems

    International Nuclear Information System (INIS)

    Feng, Lejun; Zheng, Danxing; Huang, Weijia

    2016-01-01

    Highlights: • Three new working pairs are proposed for absorption power cycle. • Sync-measured the solubility and absorption enthalpy data at 303.15 K. • Thermokinetic experiment is consistent with the previous thermodynamics study. - Abstract: In this work, three new working pairs, {fluoroethane (HFC161) + dimethylether tetraethylene glycol (DMETEG)}, {HFC161 + dimethylether triethylene glycol (DMETrEG)} and {HFC161 + dimethylether diethylene glycol (DMEDEG)}, are proposed for absorption power cycle. The working pairs are assessed from both thermodynamics and thermokinetic perspective. By combining the microcalorimetry and isothermal synthesis methods, an experimental apparatus was developed to simultaneously obtain the microcalorimetry and vapour–liquid equilibrium data. Then, the solubility and absorption enthalpy data of the three new working pairs were sync-measured at 303.15 K by this sync-measurement experimental apparatus. The thermodynamics data indicated that the affinities of the three working pairs increased from strong to weak in the following order: HFC161 + DMETEG > HFC161 + DMETrEG > HFC161 + DMEDEG. Then the thermokinetic parameters of the absorption rate constant and activation energy were analysed based on the thermokinetic experiment at (303.15, 313.15, 323.15, and 333.15) K. As a result, the affinities of the three working pairs are consistent with the previous thermodynamics study. In addition, the intermolecular interactions within the three systems were analysed according to the intermolecular hydrogen bonds; overall, the (HFC161 + DMETEG) system is considered to be the potential option for applications.

  18. A subchronic dermal exposure study of diethylene glycol monomethyl ether and ethylene glycol monomethyl ether in the male guinea pig.

    Science.gov (United States)

    Hobson, D W; D'Addario, A P; Bruner, R H; Uddin, D E

    1986-02-01

    Diethylene glycol monomethyl ether (DEGME) has been selected as a replacement anti-icing additive for ethylene glycol monomethyl ether (EGME) in Navy jet aircraft fuel. This experiment was performed to determine whether DEGME produced similar toxicity to EGME following dermal exposure. Male guinea pigs were dermally exposed to 1.00, 0.20, 0.04, or 0 (control) g/kg/day DEGME for 13 weeks, 5 days/week, 6 hr/day. Another group of animals was similarly exposed to 1.00 g/kg/day EGME. Body weights as well as testicular and splenic weights were reduced as a result of exposure to EGME, DEGME-exposed animals exhibited decreased splenic weight in the high- and medium-dose (1.00 and 0.20 g/kg/day) exposure groups only. Hematologic changes in EGME-exposed animals included mild anemia with increased erythrocytic mean corpuscular volumes and a lymphopenia with increased neutrophils. Similar hematological changes were not observed in any animals exposed to DEGME. Serum creatine kinase activity was increased in animals exposed to EGME, and serum lactate dehydrogenase activity was increased in EGME and 1.00 g/kg/day DEGME-exposed animals. In general, DEGME produced minimal toxicological changes following dermal exposure, whereas the toxicological changes observed following similar exposure to EGME were much more profound.

  19. Polymerization Using Phosphazene Bases

    KAUST Repository

    Zhao, Junpeng

    2015-09-01

    In the recent rise of metal-free polymerization techniques, organic phosphazene superbases have shown their remarkable strength as promoter/catalyst for the anionic polymerization of various types of monomers. Generally, the complexation of phosphazene base with the counterion (proton or lithium cation) significantly improves the nucleophilicity of the initiator/chain end resulting in highly enhanced polymerization rates, as compared with conventional metalbased initiating systems. In this chapter, the general features of phosphazenepromoted/catalyzed polymerizations and the applications in macromolecular engineering (synthesis of functionalized polymers, block copolymers, and macromolecular architectures) are discussed with challenges and perspectives being pointed out.

  20. Controlled release of potassium chloride from radiation-polymerized copolymer matrices

    International Nuclear Information System (INIS)

    Yoshida, Masaru; Kumakura, Minoru; Kaetsu, Isao

    1979-01-01

    Release behavior of potassium chloride (KCl) from the flat circular copolymer composites, obtained by radiation-induced polymerization at low temperatures, was studied. The release rate agreed with the first-order kinetics based on the Noyes-Whitney equation in relation to the swelling of the composites. Release profiles of KCl from copolymer composites was affected by monomer composition between hydroxyethyl acrylate (HEA) and polyfunctional glass-forming monomers such as 2-hydroxyethyl methacrylate (HEMA), diethylene glycol dimethacrylate (DGDA), and trimethylolpropane trimethacrylate (TMPT) owing to change of swelling property of copolymers. The release rate decreased at HEA-poor composition in any system. In the case of hydrophobic comonomer system such as glycidyl methacrylate (GMA) and DGDA, release profile of KCl showed a minimum at 50% GMA-50% DGDA monomer composition. (author)

  1. Applied bioactive polymeric materials

    CERN Document Server

    Carraher, Charles; Foster, Van

    1988-01-01

    The biological and biomedical applications of polymeric materials have increased greatly in the past few years. This book will detail some, but not all, of these recent developments. There would not be enough space in this book to cover, even lightly, all of the major advances that have occurred. Some earlier books and summaries are available by two of this book's Editors (Gebelein & Carraher) and these should be consul ted for additional information. The books are: "Bioactive Polymeric Systems" (Plenum, 1985); "Polymeric Materials In Medication" (Plenum, 1985); "Biological Acti vi ties of Polymers" (American Chemical Society, 1982). Of these three, "Bioacti ve Polymeric Systems" should be the most useful to a person who is new to this field because it only contains review articles written at an introductory level. The present book primarily consists of recent research results and applications, with only a few review or summary articles. Bioactive polymeric materials have existed from the creation of life...

  2. Bioaugmentation for treatment of full-scale diethylene glycol monobutyl ether (DGBE) wastewater by Serratia sp. BDG-2

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Maoxia; Fan, Rong; Zou, Wenhui; Zhou, Houzhen [Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Tan, Zhouliang, E-mail: tanzhl@cib.ac.cn [Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Li, Xudong [Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China)

    2016-05-15

    Highlights: • BDG-2 grew well at 30 °C, pH 9 and 2000 mg L{sup −1} of initial DGBE concentration. • It could obtain 96.92% of COD (generated by DGBE) removal efficiency in 39.9 h. • The technological matching was made based on the characteristics of DGBE wastewater and BDG-2. • Stable operation of bio-augmentation treatment facilities was finally accomplished. - Abstract: A novel bacterial strain BDG-2 was isolated and used to augment the treatment of silicon plate manufacturing wastewater that primarily contains diethylene glycol monobutyl ether (DGBE). BDG-2 was identified as a Serratia sp. Under the optimal conditions of 30 °C, pH 9 and DGBE concentration of 2000 mg L{sup −1}, the bioaugmented system achieved 96.92% COD removal after 39.9 h. Laboratory-scale technological matching results indicated that, in a biofilm process with the addition of 100 mg L{sup −1} ammonia and 5 mg L{sup −1} total phosphorus (TP), 70.61% COD removal efficiency could be obtained in 46 h. Addition of polyaluminium chloride (PAC) to the reactors during the suspension process enhanced the settleability of the BDG-2 culture. Subsequently, successful start-up and stable operation of a full-scale bioaugmented treatment facilities were accomplished, and the volumetric organic load in the plug-flow aeration tank was 2.17 ± 0.81 kg m{sup −3} d{sup −1}. The effluent COD of the facilities was stable and always below 100 mg L{sup −1}.

  3. Bioaugmentation for treatment of full-scale diethylene glycol monobutyl ether (DGBE) wastewater by Serratia sp. BDG-2

    International Nuclear Information System (INIS)

    Chen, Maoxia; Fan, Rong; Zou, Wenhui; Zhou, Houzhen; Tan, Zhouliang; Li, Xudong

    2016-01-01

    Highlights: • BDG-2 grew well at 30 °C, pH 9 and 2000 mg L"−"1 of initial DGBE concentration. • It could obtain 96.92% of COD (generated by DGBE) removal efficiency in 39.9 h. • The technological matching was made based on the characteristics of DGBE wastewater and BDG-2. • Stable operation of bio-augmentation treatment facilities was finally accomplished. - Abstract: A novel bacterial strain BDG-2 was isolated and used to augment the treatment of silicon plate manufacturing wastewater that primarily contains diethylene glycol monobutyl ether (DGBE). BDG-2 was identified as a Serratia sp. Under the optimal conditions of 30 °C, pH 9 and DGBE concentration of 2000 mg L"−"1, the bioaugmented system achieved 96.92% COD removal after 39.9 h. Laboratory-scale technological matching results indicated that, in a biofilm process with the addition of 100 mg L"−"1 ammonia and 5 mg L"−"1 total phosphorus (TP), 70.61% COD removal efficiency could be obtained in 46 h. Addition of polyaluminium chloride (PAC) to the reactors during the suspension process enhanced the settleability of the BDG-2 culture. Subsequently, successful start-up and stable operation of a full-scale bioaugmented treatment facilities were accomplished, and the volumetric organic load in the plug-flow aeration tank was 2.17 ± 0.81 kg m"−"3 d"−"1. The effluent COD of the facilities was stable and always below 100 mg L"−"1.

  4. Diglycolic acid is the nephrotoxic metabolite in diethylene glycol poisoning inducing necrosis in human proximal tubule cells in vitro.

    Science.gov (United States)

    Landry, Greg M; Martin, Sarah; McMartin, Kenneth E

    2011-11-01

    Diethylene glycol (DEG), a solvent and chemical intermediate, can produce an acute toxic syndrome, the hallmark of which is acute renal failure due to cortical tubular degeneration and proximal tubular necrosis. DEG is metabolized to two primary metabolites, 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA), which are believed to be the proximate toxicants. The precise mechanism of toxicity has yet to be elucidated, so these studies were designed to determine which metabolite was responsible for the proximal tubule cell death. Human proximal tubule (HPT) cells in culture, obtained from normal cortical tissue and passaged 3-6 times, were incubated with increasing concentrations of DEG, 2-HEAA, or DGA separately and in combination for 48 h at pH 6 or 7.4, and various parameters of necrotic and apoptotic cell death were measured. DEG and 2-HEAA did not produce any cell death. DGA produced dose-dependent necrosis at concentrations above 25 mmol/l. DGA did not affect caspase-3 activity and increased annexin V staining only in propidium iodide-stained cells. Hence, DGA induced necrosis, not apoptosis, as corroborated by severe depletion of cellular adenosine triphosphate levels. DGA is structurally similar to citric acid cycle intermediates that are taken up by specific transporters in kidney cells. HPT cells, incubated with N-(p-amylcinnamoyl)anthranilic acid, a sodium dicarboxylate-1 transporter inhibitor showed significantly decreased cell death compared with DGA alone. These studies demonstrate that DGA is the toxic metabolite responsible for DEG-induced proximal tubular necrosis and suggest a possible transporter-mediated uptake of DGA leading to toxic accumulation and cellular dysfunction.

  5. Diglycolic acid, the toxic metabolite of diethylene glycol, chelates calcium and produces renal mitochondrial dysfunction in vitro.

    Science.gov (United States)

    Conrad, Taylor; Landry, Greg M; Aw, Tak Yee; Nichols, Royce; McMartin, Kenneth E

    2016-07-01

    Diethylene glycol (DEG) has caused many cases of acute kidney injury and deaths worldwide. Diglycolic acid (DGA) is the metabolite responsible for the renal toxicity, but its toxic mechanism remains unclear. To characterize the mitochondrial dysfunction produced from DGA by examining several mitochondrial processes potentially contributing to renal cell toxicity. The effect of DGA on mitochondrial membrane potential was examined in normal human proximal tubule (HPT) cells. Isolated rat kidney mitochondria were used to assess the effects of DGA on mitochondrial function, including respiratory parameters (States 3 and 4), electron transport chain complex activities and calcium-induced opening of the mitochondrial permeability transition pore. DGA was compared with ethylene glycol tetraacetic acid (EGTA) to determine calcium chelating ability. DGA cytotoxicity was assessed using lactate dehydrogenase leakage from cultured proximal tubule cells. DGA decreased the mitochondrial membrane potential in HPT cells. In rat kidney mitochondria, DGA decreased State 3 respiration, but did not affect State 4 respiration or the ADP/O ratio. DGA reduced glutamate/malate respiration at lower DGA concentrations (0.5 mmol/L) than succinate respiration (100 mmol/L). DGA inhibited Complex II activity without altering Complex I, III or IV activities. DGA blocked calcium-induced mitochondrial swelling, indicating inhibition of the calcium-dependent mitochondrial permeability transition. DGA and EGTA reduced the free calcium concentration in solution in an equimolar manner. DGA toxicity and mitochondrial dysfunction occurred as similar concentrations. DGA inhibited mitochondrial respiration, but without uncoupling oxidative phosphorylation. The more potent effect of DGA on glutamate/malate respiration and the inhibition of mitochondrial swelling was likely due to its chelation of calcium. These results indicate that DGA produces mitochondrial dysfunction by chelating calcium to

  6. The effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic gamma-glutamyl transpeptidase.

    Science.gov (United States)

    Kawamoto, T; Matsuno, K; Kayama, F; Arashidani, K; Yoshikawa, M; Kodama, Y

    1992-11-22

    In this paper, we determined whether ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (diEGME) induce hepatic gamma-glutamyl transpeptidase activity. Male adult Wistar rats weighing 220 g were used as experimental animals. EGME (100, 300 mg/kg per day) and diEGME (500, 1000, 2000 mg/kg per day) were administered by gavage for 1, 2 or 5 days or 4 weeks. In the 4-week study, experimental animals were administered EGME or diEGME once a day orally, 5 days/week. EGME treatment increased the serum gamma-glutamyl transpeptidase (GGT) level significantly, however, diEGME did not. The activities of three other enzymes (SGOT, SGPT and ALP) in serum were not altered by EGME or diEGME treatment and thus there was no biochemical indices of hepatic damage by EGME or diEGME. EGME treatment increased the GGT activities in the liver and lungs. Of the organs examined, the induction of GGT was the greatest in the liver. The inducibility in the liver was 216% for the 5-day treatment and 460% for the 4-week treatment. A dose-dependent increase of hepatic microsomal GGT activity by EGME was observed. On the other hand, renal GGT activities were declined to 72% and 60% of control by the 5-day and 4-week EGME treatments, respectively. DiEGME did not affect the GGT activities in any of the tissues except those of the brain. In the histochemical study, most hepatocytes at the periportal zones were stained with GGT staining after the 4-week treatment. However, the hepatocytes at the central zones were negative.

  7. A label-free multi-functionalized electrochemical aptasensor based on a Fe_3O_4@3D-rGO@plasma-polymerized (4-vinyl pyridine) nanocomposite for the sensitive detection of proteins in whole blood

    International Nuclear Information System (INIS)

    Fang, Shaoming; Dong, Xiaodong; Liu, Shunli; Penng, Donglai; He, Linghao; Wang, Minghua; Fu, Guodong; Feng, Xiaozhong; Zhang, Zhihong

    2016-01-01

    In this paper, we report a novel label-free electrochemical aptasensor for detecting proteins in whole blood based on a three-component nanocomposite, in which ferriferrous oxide and three-dimensional graphene nanocomposite were modified with the plasma-polymerized 4-vinyl pyridine (Fe_3O_4@3D-rGO@PP4VP). In this novel sensing strategy, large amounts of amino groups in PP4VP facilitated the immobilization of aptamer strands via the strong electrostatic interaction between positively charged ammonium groups of the nanocomposites and negatively charged phosphate groups of aptamers. In the presence of thrombin, LYS (LYS), and platelet-derived growth factor-BB (PDGF-BB), the adsorbed aptamer strands on the developed nanocomposite surface caught the targeted proteins at the electrode interface. The aptamer preferred to be a barrier for electrons and inhibited electron transfer, leading to the decreased peak current of cyclic voltammetry measurements and the increased electron transfer resistance of electrochemical impedance spectroscopy. The determination of the thrombin, PDGF-BB, and LYS concentrations with this novel strategy showed low detection limits of 4.5, 29.4, and 14 pg·mL"−"1, and the analytical ranges extend from 0.01 to 50, 0.1 to 100, and 0.1 to 200 ng·mL"−"1, respectively. The resultant aptasensor exhibited high selectivity, acceptable reproducibility, and stability toward thrombin. The aptasensor could be used to detect thrombin in whole blood samples, thereby suggesting its possible application in clinical settings.

  8. Polymeric bicontinuous microemulsions

    DEFF Research Database (Denmark)

    Bates, F.S.; Maurer, W.W.; Lipic, P.M.

    1997-01-01

    High molecular weight block copolymers can be viewed as macromolecular surfactants when blended with thermodynamically incompatible homopolymers. This Letter describes the formation of polymeric bicontinuous microemulsions in nurtures containing a model diblock copolymer and two homopolymers. Alt...

  9. Polymerization Using Phosphazene Bases

    KAUST Repository

    Zhao, Junpeng; Hadjichristidis, Nikolaos; Schlaad, Helmut

    2015-01-01

    . In this chapter, the general features of phosphazenepromoted/catalyzed polymerizations and the applications in macromolecular engineering (synthesis of functionalized polymers, block copolymers, and macromolecular architectures) are discussed with challenges

  10. Radical-Mediated Enzymatic Polymerizations

    Science.gov (United States)

    Zavada, Scott R.; Battsengel, Tsatsral; Scott, Timothy F.

    2016-01-01

    Polymerization reactions are commonly effected by exposing monomer formulations to some initiation stimulus such as elevated temperature, light, or a chemical reactant. Increasingly, these polymerization reactions are mediated by enzymes―catalytic proteins―owing to their reaction efficiency under mild conditions as well as their environmental friendliness. The utilization of enzymes, particularly oxidases and peroxidases, for generating radicals via reduction-oxidation mechanisms is especially common for initiating radical-mediated polymerization reactions, including vinyl chain-growth polymerization, atom transfer radical polymerization, thiol–ene step-growth polymerization, and polymerization via oxidative coupling. While enzyme-mediated polymerization is useful for the production of materials intended for subsequent use, it is especially well-suited for in situ polymerizations, where the polymer is formed in the place where it will be utilized. Such polymerizations are especially useful for biomedical adhesives and for sensing applications. PMID:26848652

  11. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor

    2015-01-22

    The present application offers a solution to the current problems associated with recovery and recycling of precious metals from scrap material, discard articles, and other items comprising one or more precious metals. The solution is premised on a microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  12. A new cell for temperature-dependent X-ray absorption spectroscopy of liquid solutions: application to PbBr2 solutions in diethylene glycol.

    Science.gov (United States)

    Lützenkirchen-Hecht, D; Oldag, T; Keil, P; Keller, H L; Frahm, R

    2005-03-01

    An in situ cell has been constructed for temperature-dependent X-ray absorption experiments (EXAFS and XANES) of lead bromine (PbBr2) solutions in diethylene glycol in the temperature range from room temperature up to about 433 K. The solution is kept in a thermostated container made of carbon-reinforced teflon between two thin chemically inert quartz glass windows with a high transmission for hard X-rays. The construction of the cell ensures that these X-ray windows are thermalized so that any possible precipitation of solid products from the solution is inhibited. The cell consists mainly of two hermetically sealed teflon containers for the thermostating fluid (silicon oil) that were fitted together in such a way that a small and variable volume (approximately 2-4 cm3) for the liquid under investigation was achieved. A small thermocouple in a glass enclosure was placed in the solution to maintain temperature control and feedback to the thermostat. The cell design and its performance for temperature-dependent in situ investigations with X-rays are reported. Some preliminary results obtained for PbBr2 solutions in diethylene glycol are given.

  13. Validation of an analytical methodology for the determination of diethylene glycol and ethylene glycol as impurities in glycerin and propylene glycol

    International Nuclear Information System (INIS)

    Rosabal Cordovi, Ursula M; Fonseca Gola, Antonio; Cordovi Velazquez, Juan M; Morales Torres, Galina

    2014-01-01

    A methodology for the quantification of diethylene glycol (DEG) and the ethylene glycol (EG) impurities by gas Chromatography with flame ionization detector in glycerol and propylene glycol samples was developed and validated. It was selected dimethyl sulphoxide as internal standard. It was used hydrogen as carrier and auxiliary gas. The temperature program was 100°C holding one minute, then ramp to rate of 7.5°C/ min up to 200 °C. A Restek 624 column was used, with a flow in column of 4.20 ml/ min. Temperatures of the injector and detector were set at 220°C and 250 °C, respectively. The linearity was determined at 25-75 ?μg/ml as interval of concentrations for both impurities with correlation coefficients larger than 0.999. Detection Limits were settled down in 0.0350 μ?g/ml to the diethylene glycol, and 0.0572 μg/ml to ethylene glycol, while the quantitation limits were 0.1160 μ?g/ml to DEG and 0.1897 μg/ml to the EG. The recoveries were 99.98 % and 100.00 %, respectively; with RSD % 1.18 % to DEG, and 0.60 % to the EG. The obtained results demonstrated that the methodology was linear, accurate, robustness, sensitive and selective to be used in the determination of both impurities in the quality control of the glycerol and propylene glycol as raw materials

  14. Mechanistic studies of plasma polymerization of allylamine

    Czech Academy of Sciences Publication Activity Database

    Chourkov, A.; Biederman, H.; Slavinská, D.; Hanley, L.; Macková, Anna; Grinevich, A.; Boldryeva, H.

    2005-01-01

    Roč. 109, č. 48 (2005), s. 23086-23095 ISSN 1520-6106 Institutional research plan: CEZ:AV0Z10480505 Keywords : quartz-crystal microbalance * atomic-force microscopy * guide mode spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.033, year: 2005

  15. Radiation induced emulsion polymerization

    International Nuclear Information System (INIS)

    Stannett, V.T.; Stahel, E.P.

    1990-01-01

    High energy radiation is particularly favored for the initiation of emulsion polymerization. The yield of free radicals, for example, from the radiolysis of the aqueous phase, is high; G(radical) values of 5-7. In addition, the rather special kinetics associated with emulsion polymerization lead, in general, to very large kinetic chain lengths, even with 'non-ideal' monomers such as vinyl acetate. Together, high polymerization rates at low doses become possible. There are some important advantages of radiation polymerization compared with chemical initiators, such as potassium persulfate. Perhaps the most important among them is the temperature independence of the initiation step. This makes low temperature polymerization very accessible. With monomers such as vinyl acetate, where chain termination to monomer is predominant, low temperatures lead to often highly desirable higher molecular weights. With styrene, the classical ideally behaved monomer, there are the advantages such as, for example, the feasibility of using cationic monomers. These and some attendant disadvantages are discussed in detail, including pilot plant studies

  16. Inflation of a Polymeric Menbrane

    DEFF Research Database (Denmark)

    Kristensen, Susanne B.; Larsen, Johannes R.; Hassager, Ole

    1998-01-01

    We consider an axisymmetric polymeric membrane inflated by a uniform pressure difference acting across the membrane.......We consider an axisymmetric polymeric membrane inflated by a uniform pressure difference acting across the membrane....

  17. Polymerized and functionalized triglycerides

    Science.gov (United States)

    Plant oils are useful sustainable raw materials for the development of new chemical products. As part of our research emphasis in sustainability and green polymer chemistry, we have explored a new method for polymerizing epoxidized triglycerides with the use of fluorosulfonic acid. Depending on the ...

  18. Polymerization by radiation. Application

    International Nuclear Information System (INIS)

    Romero, M.; Fernandez Miranda, J.

    1997-01-01

    Achieved results of the research work done in the field of radiation polymerization are summarized. Developing new chromatographic matrices, the radiation grafting of Glycidyl methacrylate on the surface of Low Density Polyethylene beads was studied. The dependence of both, the grafted degree and width of the grafted layer, with the radiation dose applied, is presented

  19. Polymeric micelles as a drug carrier for tumor targeting

    Directory of Open Access Journals (Sweden)

    Neha M Dand

    2013-01-01

    Full Text Available Polymeric micelle can be targeted to tumor site by passive and active mechanism. Some inherent properties of polymeric micelle such as size in nanorange, stability in plasma, longevity in vivo, and pathological characteristics of tumor make polymeric micelles to be targeted at the tumor site by passive mechanism called enhanced permeability and retention effect. Polymeric micelle formed from the amphiphilic block copolymer is suitable for encapsulation of poorly water soluble, hydrophobic anticancer drugs. Other characteristics of polymeric micelles such as separated functionality at the outer shell are useful for targeting the anticancer drug to tumor by active mechanisms. Polymeric micelles can be conjugated with many ligands such as antibodies fragments, epidermal growth factors, α2 -glycoprotein, transferrine, and folate to target micelles to cancer cells. Application of heat and ultrasound are the alternative methods to enhance drug accumulation in tumoral cells. Targeting using micelles can also be done to tumor angiogenesis which is the potentially promising target for anticancer drugs. This review summarizes about recently available information regarding targeting the anticancer drug to the tumor site using polymeric micelles.

  20. RAFT polymerization mediated bioconjugation strategies

    OpenAIRE

    Bulmuş, Volga

    2011-01-01

    This review aims to highlight the use of RAFT polymerization in the synthesis of polymer bioconjugates. It covers two main bioconjugation strategies using the RAFT process: (i) post-polymerization bioconjugations using pre-synthesized reactive polymers, and (ii) bioconjugations via in situ polymerization using biomolecule-modified monomers or chain transfer agents. © 2011 The Royal Society of Chemistry.

  1. Densities, Ultrasonic Speeds, and Excess Properties of Binary Mixtures of Diethylene Glycol with 1-Butanol, 2-Butanol, and 1,4-Butanediol at Different Temperatures

    Science.gov (United States)

    Ali, Anwar; Ansari, Sana; Uzair, Sahar; Tasneem, Shadma; Nabi, Firdosa

    2015-11-01

    Densities ρ and ultrasonic speeds u for pure diethylene glycol, 1-butanol, 2-butanol, and 1,4-butanediol and for their binary mixtures over the entire composition range were measured at 298.15 K, 303.15 K, 308.15 K, and 313.15 K. Using these data, the excess molar volumes, VE_m, deviations in isentropic compressibilities, {\\varDelta }ks, apparent molar volumes, V_{φi} , partial molar volumes, overline{V}_{m,i} , and excess partial molar volumes, overline{V}_{m,i}^E , have been calculated over the entire composition range, and also the excess partial molar volumes of the components at infinite dilution, overline{V}_{m,i}^{E,infty } have been calculated. The excess functions have been correlated using the Redlich-Kister equation at different temperatures. The variations of these derived parameters with composition and temperature are presented graphically.

  2. Biological effects of diethylene glycol (DEG) and produced waters (PWs) released from offshore activities: a multi-biomarker approach with the sea bass Dicentrarchus labrax.

    Science.gov (United States)

    Stefania, Gorbi; Maura, Benedetti; Claudia, Virno Lamberti; Barbara, Pisanelli; Ginevra, Moltedo; Francesco, Regoli

    2009-11-01

    Diethylene glycol (DEG) is largely used during oil and gas exploitation by offshore platforms. The aim of this work was to investigate if this compound induces direct molecular/cellular effects in marine organisms, or indirectly modulate those of produced waters (PWs). Sea bass (Dicentrarchus labrax) were exposed to DEG dosed alone or in combination with PWs from an Adriatic platform. A wide array of analysed biomarkers included cytochrome P450-dependent enzymatic activity, bile metabolites, glutathione S-transferases, acetylcholinesterase, peroxisomal proliferation, antioxidant defences (catalase, glutathione reductase, glutathione peroxidases, glutathione), total oxyradical scavenging capacity, malondialdehyde and DNA integrity (single strand breaks and frequency of micronuclei). Results did not reveal marked effects of DEG, while PWs influenced the biotransformation system, the oxidative status and the onset of genotoxic damages. Co-exposures caused only limited differences of biomarker responses at some experimental conditions, overall suggesting a limited biological impact of DEG at levels normally deriving from offshore activities.

  3. Solvothermal synthesis of Zn{sub 2}GeO{sub 4}:Mn{sup 2+} nanophosphor in water/diethylene glycol system

    Energy Technology Data Exchange (ETDEWEB)

    Takeshita, Satoru; Honda, Joji [Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Isobe, Tetsuhiko, E-mail: isobe@applc.keio.ac.jp [Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Sawayama, Tomohiro; Niikura, Seiji [SINLOIHI Company, Limited, 2-19-12 Dai, Kamakura 247-8550 (Japan)

    2012-05-15

    The influence of aging of the suspension containing the amorphous precusors on structural, compositional and photoluminescent properties is studied to understand the mechanism on the formation of Zn{sub 2}GeO{sub 4}:Mn{sup 2+} nanoparticles during the solvothermal reaction in the water/diethylene glycol mixed solvent. Aging at 200 Degree-Sign C for 20 min forms the crystalline Zn{sub 2}GeO{sub 4} nanorods and then they grow up to {approx} 50 nm in mean length after aging for 240 min. Their interplanar spacing of (410) increases with increasing the aging time. The photoluminescence intensity corresponding to the d-d transition of Mn{sup 2+} increases with increasing the aging time up to 120 min, and then decreases after aging for 240 min. The photoluminescence lifetime decreases with increasing the aging time, indicating the locally concentrated Mn{sup 2+} ions. These results reveal that Mn{sup 2+} ions gradually replace Zn{sup 2+} ions near surface through repeating dissolusion and precipitation processes during prolonged aging after the complete crystallization of Zn{sub 2}GeO{sub 4}. - Graphical abstract: TEM images of Zn{sub 2}GeO{sub 4}:Mn{sup 2+} nanoparticles aged at 200 Degree-Sign C for different aging times in the mixed solvent of water and diethylene glycol. Highlights: Black-Right-Pointing-Pointer Mechanism on formation of Zn{sub 2}GeO{sub 4}:Mn{sup 2+} nanophosphor under solvothermal condition. Black-Right-Pointing-Pointer Zn{sub 2}GeO{sub 4} nanorods crystallize via amorphous precursors. Black-Right-Pointing-Pointer Gradual substitution of Mn{sup 2+} during prolonged aging. Black-Right-Pointing-Pointer Such an inhomogeneous Mn{sup 2+} doping process results in concentration quenching.

  4. Radiation polymerization of tetrafluoroethylene

    International Nuclear Information System (INIS)

    Kadoi, H.; Lugao, A.B.; Oikawa, H.

    1984-01-01

    Tetrafluoroethylene (TFE) monomer was obtained by means of the pyrolysis of chlorodifluoromethane (R-22). The experiments were carried out in quartz tube with temperature between 700 0 and 800 0 C. The principal reaction of the pyrolysis is considered to be: 2CHClF2 ----> C 2 F 4 +2HCl. However, by-products such as HF, C 3 F 6 , C 2 HClF 4 , C 4 F 8 etc are also produced in the pyrolysis process. The conversions of R-22 varied from 30 to 50%, depending upon the temperature, pressure and flow rate of R-22 in the furnace. Finally the TFE monomer of purity higher than 99.98% was obtained by fractional distillation in low temperatures ranging from -10 0 to -30 0 C. The bulk polymerization of this monomer induced by γ-rays from 3000Ci cobalt-60 source was studied at various temperatures (room temperature, 0 0 , -23 0 and -78 0 C). The monomers were introduced into stainless steel vessels of 15 and 60 ml volume under vacuum. The control of polymerization reaction was rather hard at temperatures higher than -23 0 C due to the difficulty of removing the heat of reaction. However, the polymerization at -78 0 C was very easy to control. The white polymer particles were obtained in agglomerated state. The IR spectra of the polymers were consistent with those of commercial products. The melting points of samples were between 326 0 and 331 0 C. (Author) [pt

  5. Radiation chemistry of polymeric system

    International Nuclear Information System (INIS)

    Machi, Sueo; Ishigaki, Isao

    1978-01-01

    Among wide application of radiation in the field of polymer chemistry, practices of polymerization, graft polymerization, bridging, etc. are introduced hereinafter. As for the radiation sources of radiation polymerization, in addition to the 60 Co-γ ray with long permeation distance which has been usually applied, electron beam accelerators with high energy, large current and high reliability have come to be produced, and the liquid phase polymerization by electron beam has attracted attention industrially. Concerning polymerizing reactions, explanations were given to electron beam polymerization under high dose rate, the polymerization in supercooling state or under high pressure, and emulsifying polymerization. As for radiation bridging, radiation is applied for the bridging of hydrogel, acceleration of bridging and improvement of radiation resistance. It is also utilized for reforming membranes by graft polymerization, and synthesis of polymers for medical use. Application of fixed enzymes in the medical field has been investigated by fixing various enzymes by low temperature γ-ray polymerization with glassy monomers such as HEMA. (Kobatake, H.)

  6. A New Role for CO2: Controlling Agent of the Anionic Ring-Opening Polymerization of Cyclic Esters

    KAUST Repository

    Varghese, Jobi K.; Goncalves, Theo; Huang, Kuo-Wei; Hadjichristidis, Nikolaos; Gnanou, Yves; Feng, Xiaoshuang

    2017-01-01

    Conventional anionic ring-opening of polymerization (AROP) of cyclic esters suffers from the nonselective and concomitant attack of the monomer and of the polymer chains by the growing active species, which results in polyester samples with uncontrolled molar masses and broad polydispersity due to the competition between propagation and transesterification reactions. In this report, we describe a new AROP system mediated by a controlled amount of CO2 which prevents transesterification reactions from occurring. Using lithium monomethyl diethylene glycoxide (MEEOLi) as initiator and 1.5 equiv of CO2, ε-caprolactone could be polymerized under truly “living” conditions in dichloromethane (DCM) at 70 °C, as evidenced by the control of molar masses, the narrow polydispersity indexes (Mn up to ∼40 kg/mol, Đ < 1.16), and also successful chain extension experiments. Lithium carbonate used as initiator in the presence of 0.5 equiv of CO2 afforded similar polymerization results. Experiments carried out with other alkoxide salts and solvents demonstrate that CO2 is indispensable as well as lithium and noncoordinating solvents for the suppression of transesterifications. A similar strategy was applied for the AROP of l-lactide (LLA). At −20 °C, LLA could be polymerized under living conditions with undetectable level of transesterification as demonstrated by MALDI-ToF analysis. To account for the polymerization mechanism occurring in the presence of a slight excess of CO2, we resorted to computational studies. It appears that a fast equilibrium takes place between two tetrameric aggregates, one dormant comprising four carbonates (RCO3Li)4, and an active one involving three carbonates and one alkoxide (RCO3Li)3(ROLi). The latter is shown to selectively ring-open cyclic ester without indulging in transesterifications like (ROLi)4 precursors.

  7. A New Role for CO2: Controlling Agent of the Anionic Ring-Opening Polymerization of Cyclic Esters

    KAUST Repository

    Varghese, Jobi K.

    2017-08-15

    Conventional anionic ring-opening of polymerization (AROP) of cyclic esters suffers from the nonselective and concomitant attack of the monomer and of the polymer chains by the growing active species, which results in polyester samples with uncontrolled molar masses and broad polydispersity due to the competition between propagation and transesterification reactions. In this report, we describe a new AROP system mediated by a controlled amount of CO2 which prevents transesterification reactions from occurring. Using lithium monomethyl diethylene glycoxide (MEEOLi) as initiator and 1.5 equiv of CO2, ε-caprolactone could be polymerized under truly “living” conditions in dichloromethane (DCM) at 70 °C, as evidenced by the control of molar masses, the narrow polydispersity indexes (Mn up to ∼40 kg/mol, Đ < 1.16), and also successful chain extension experiments. Lithium carbonate used as initiator in the presence of 0.5 equiv of CO2 afforded similar polymerization results. Experiments carried out with other alkoxide salts and solvents demonstrate that CO2 is indispensable as well as lithium and noncoordinating solvents for the suppression of transesterifications. A similar strategy was applied for the AROP of l-lactide (LLA). At −20 °C, LLA could be polymerized under living conditions with undetectable level of transesterification as demonstrated by MALDI-ToF analysis. To account for the polymerization mechanism occurring in the presence of a slight excess of CO2, we resorted to computational studies. It appears that a fast equilibrium takes place between two tetrameric aggregates, one dormant comprising four carbonates (RCO3Li)4, and an active one involving three carbonates and one alkoxide (RCO3Li)3(ROLi). The latter is shown to selectively ring-open cyclic ester without indulging in transesterifications like (ROLi)4 precursors.

  8. Apparatus and method for oxidation and stabilization of polymeric materials

    Science.gov (United States)

    Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Sherman, Daniel M [Knoxville, TN

    2009-05-19

    An apparatus for treating polymeric materials comprises a treatment chamber adapted to maintain a selected atmosphere; a means for supporting the polymeric material within the chamber; and, a source of plasma-derived gas containing at least one reactive oxidative species whereby the polymer is stabilized and cross linked through exposure to the oxidative species in the chamber at a selected temperature. The polymer may be directly exposed to the plasma, or alternatively, the plasma may be established in a separate volume from which the reactive species may be extracted and introduced into the vicinity of the polymer. The apparatus may be configured for either batch-type or continuous-type processing. The apparatus and method are especially useful for preparing polymer fibers, particularly PAN fibers, for later carbonization treatments.

  9. Packaging based on polymeric materials

    Directory of Open Access Journals (Sweden)

    Jovanović Slobodan M.

    2005-01-01

    Full Text Available In the past two years the consumption of common in the developed countries world wide (high tonnage polymers for packaging has approached a value of 50 wt.%. In the same period more than 50% of the packaging units on the world market were made of polymeric materials despite the fact that polymeric materials present 17 wt.% of all packaging materials. The basic properties of polymeric materials and their environmental and economical advantages, providing them such a position among packaging materials, are presented in this article. Recycling methods, as well as the development trends of polymeric packaging materials are also presented.

  10. Phosphazene-promoted anionic polymerization

    KAUST Repository

    Zhao, Junpeng

    2014-01-01

    In the recent surge of metal-free polymerization techniques, phosphazene bases have shown their remarkable potential as organic promoters/catalysts for the anionic polymerization of various types of monomers. By complexation with the counterion (e.g. proton or lithium cation), phosphazene base significantly improve the nucleophilicity of the initiator/chain-end resulting in rapid and usually controlled anionic/quasi-anionic polymerization. In this review, we will introduce the general mechanism, i.e. in situ activation (of initiating sites) and polymerization, and summarize the applications of such a mechanism on macromolecular engineering toward functionalized polymers, block copolymers and complex macromolecular architectures.

  11. Synthesis of magnetic polymeric microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Gervald, A Yu; Gritskova, Inessa A; Prokopov, Nikolai I [M.V. Lomonosov Moscow State Academy of Fine Chemical Technology, Moscow (Russian Federation)

    2010-05-13

    The key types of magnetic polymeric microspheres are considered. Methods of synthesis of different types of magnetic nanoparticles and of preparation of stable magnetic fluids on their basis are outlined. The overview of the methods for the manufacture of magnetic polymeric microspheres is presented. The effect of the synthesis conditions on the characteristics of magnetic polymeric microspheres such as the diameter and the particle size distribution and the content of magnetic material is discussed by particular examples. The application fields of magnetic polymeric microspheres are briefly surveyed.

  12. Synthesis of magnetic polymeric microspheres

    International Nuclear Information System (INIS)

    Gervald, A Yu; Gritskova, Inessa A; Prokopov, Nikolai I

    2010-01-01

    The key types of magnetic polymeric microspheres are considered. Methods of synthesis of different types of magnetic nanoparticles and of preparation of stable magnetic fluids on their basis are outlined. The overview of the methods for the manufacture of magnetic polymeric microspheres is presented. The effect of the synthesis conditions on the characteristics of magnetic polymeric microspheres such as the diameter and the particle size distribution and the content of magnetic material is discussed by particular examples. The application fields of magnetic polymeric microspheres are briefly surveyed.

  13. Plasma processing: Technologies and applications

    International Nuclear Information System (INIS)

    Naddaf, M.; Saloum, S.

    2005-01-01

    This study aims to present the fundamentals of physics of plasmas, methods of generation, diagnostics, and applications for processing of materials. The first chapter defines plasma in general as well as its main parameters, the most important differential equations in plasma physics, and classifies the types of plasmas. the various methods and techniques to create and sustain plasma are presented in the second chapter. Chapter 3 focuses on plasma diagnostic methods and tools. While chapter 4 deals with applications of plasma processing such as; surface modification of materials, plasma ashing and etching, plasma cutting, and the environmental applications of plasma. Plasma polymerization and its various applications have been presented in more details in the last chapter. (Author)

  14. Mechanocatalytic polymerization and cross-linking in a polymeric matrix

    NARCIS (Netherlands)

    Jakobs, R.T.M.; Ma, Shuang; Sijbesma, R.P.

    2013-01-01

    A latent olefin metathesis catalyst, bearing two polymeric NHC ligands, was embedded in a semicrystalline polymer matrix containing cyclic olefins. The catalyst was activated by straining the solid material under compression, resulting in polymerization and cross-linking reactions of the monomers in

  15. Biological effects of diethylene glycol (DEG) and produced waters (PWs) released from offshore activities: A multi-biomarker approach with the sea bass Dicentrarchus labrax

    Energy Technology Data Exchange (ETDEWEB)

    Stefania, Gorbi; Maura, Benedetti [Dipartimento di Biochimica, Biologia e Genetica, Universita Politecnica delle Marche, Via Ranieri, Monte d' Ago, 60121 Ancona (Italy); Claudia, Virno Lamberti [Istituto Superiore per la Ricerca e la Protezione Ambientale (ISPRA), Via di Casalotti 300 Roma (Italy); Barbara, Pisanelli [Dipartimento di Biochimica, Biologia e Genetica, Universita Politecnica delle Marche, Via Ranieri, Monte d' Ago, 60121 Ancona (Italy); Ginevra, Moltedo [Istituto Superiore per la Ricerca e la Protezione Ambientale (ISPRA), Via di Casalotti 300 Roma (Italy); Francesco, Regoli, E-mail: f.regoli@univpm.i [Dipartimento di Biochimica, Biologia e Genetica, Universita Politecnica delle Marche, Via Ranieri, Monte d' Ago, 60121 Ancona (Italy)

    2009-11-15

    Diethylene glycol (DEG) is largely used during oil and gas exploitation by offshore platforms. The aim of this work was to investigate if this compound induces direct molecular/cellular effects in marine organisms, or indirectly modulate those of produced waters (PWs). Sea bass (Dicentrarchus labrax) were exposed to DEG dosed alone or in combination with PWs from an Adriatic platform. A wide array of analysed biomarkers included cytochrome P450-dependent enzymatic activity, bile metabolites, glutathione S-transferases, acetylcholinesterase, peroxisomal proliferation, antioxidant defences (catalase, glutathione reductase, glutathione peroxidases, glutathione), total oxyradical scavenging capacity, malondialdehyde and DNA integrity (single strand breaks and frequency of micronuclei). Results did not reveal marked effects of DEG, while PWs influenced the biotransformation system, the oxidative status and the onset of genotoxic damages. Co-exposures caused only limited differences of biomarker responses at some experimental conditions, overall suggesting a limited biological impact of DEG at levels normally deriving from offshore activities. - A biological risk for marine organisms can be excluded for DEG concentrations as those normally associated to produced waters discharged in the Adriatic Sea.

  16. Biological effects of diethylene glycol (DEG) and produced waters (PWs) released from offshore activities: A multi-biomarker approach with the sea bass Dicentrarchus labrax

    International Nuclear Information System (INIS)

    Stefania, Gorbi; Maura, Benedetti; Claudia, Virno Lamberti; Barbara, Pisanelli; Ginevra, Moltedo; Francesco, Regoli

    2009-01-01

    Diethylene glycol (DEG) is largely used during oil and gas exploitation by offshore platforms. The aim of this work was to investigate if this compound induces direct molecular/cellular effects in marine organisms, or indirectly modulate those of produced waters (PWs). Sea bass (Dicentrarchus labrax) were exposed to DEG dosed alone or in combination with PWs from an Adriatic platform. A wide array of analysed biomarkers included cytochrome P450-dependent enzymatic activity, bile metabolites, glutathione S-transferases, acetylcholinesterase, peroxisomal proliferation, antioxidant defences (catalase, glutathione reductase, glutathione peroxidases, glutathione), total oxyradical scavenging capacity, malondialdehyde and DNA integrity (single strand breaks and frequency of micronuclei). Results did not reveal marked effects of DEG, while PWs influenced the biotransformation system, the oxidative status and the onset of genotoxic damages. Co-exposures caused only limited differences of biomarker responses at some experimental conditions, overall suggesting a limited biological impact of DEG at levels normally deriving from offshore activities. - A biological risk for marine organisms can be excluded for DEG concentrations as those normally associated to produced waters discharged in the Adriatic Sea.

  17. Pre-existing liver cirrhosis reduced the toxic effect of diethylene glycol in a rat model due to the impaired hepatic alcohol dehydrogenase.

    Science.gov (United States)

    Ming Xing Huang; Xiao Mou Peng; Lin Gu; Gui Hua Chen

    2011-09-01

    Hepatic metabolizing enzymes of diethylene glycol (DEG) are impaired in liver diseases. Thus, the purpose of this study was to increase our understandings in metabolism and toxicology of DEG by clarifying the influences of pre-existing liver disease. Forty Sprague-Dawley rats with carbon tetrachloride-induced liver cirrhosis and 20 control rats were intraperitoneally administered a single dose of DEG, and randomly killed 1, 2, 5 or 8 days following exposure. Compared with control rats, the model rats had significantly higher blood CO(2)-combining power, lower blood urine nitrogen, serum creatinine and alanine aminotransferase levels on the second day and a lower mortality rate on the eighth day following DEG exposure. Enlargements of liver and kidneys and degeneration and necrosis of hepatocytes and renal tubules in the model rats was also less serious than in the control rats. Urine DEG levels were significantly higher on the first day in the model rats than the control rats (46.65 ± 8.79 mg vs 18.88 ± 6.18 mg, p activity in the model rats was significantly lower than that in the control rats, which was positively related to renal damage. The toxic effects of DEG in rats with pre-existing liver cirrhosis are significantly reduced, which may be due to the decreased hepatic ADH activity. It suggests that the metabolite of ADH is responsible for DEG poisoning, and this toxic metabolite may mainly originate in the liver.

  18. Glow discharge polymerization of α-aminopropyl triethoxy silane and the structure and properties of its polymers

    International Nuclear Information System (INIS)

    Wang Shicai; Zhou Maotang; Chen Jie

    1992-01-01

    In a capacitively coupled discharge apparatus with external electrodes, α-amonopropyltriethoxysilane (APTEOS) were polymerized and the effects of system pressure, discharge power and plasma gas on the polymerization rate were investigated. The polymer structure was studied by means of X ray diffraction, IR spectroscopy and element analysis. Some polymer properties such as thermostability, hydrophobicity and surface energy were also studied

  19. Antireflection coatings on plastics deposited by plasma ...

    Indian Academy of Sciences (India)

    In the ophthalmic industry, plastic lenses are rapidly displacing glass lenses ... Moreover, the plasma polymerization process allows deposition of optical films at room temperature, essential for plastics. ... Bulletin of Materials Science | News.

  20. Collaborative Research: Polymeric Multiferroics

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Shenqiang [Temple Univ., Philadelphia, PA (United States). College of Engineering

    2017-04-20

    The goal of this project is to investigate room temperature magnetism and magnetoelectric coupling of polymeric multiferroics. A new family of molecular charge-transfer crystals has been emerged as a fascinating opportunity for the development of all-organic electrics and spintronics due to its weak hyperfine interaction and low spin-orbit coupling; nevertheless, direct observations of room temperature magnetic spin ordering have yet to be accomplished in organic charge-transfer solids. Furthermore, room temperature magnetoelectric coupling effect hitherto known multiferroics, is anticipated in organic donor-acceptor complexes because of magnetic field effects on charge-transfer dipoles, yet this is also unexplored. The PI seeks to fundamental understanding of the control of organic crystals to demonstrate and explore room temperature multiferroicity. The experimental results have been verified through the theoretical modeling.

  1. Polymerization with freezing

    International Nuclear Information System (INIS)

    Ben-Naim, E; Krapivsky, P L

    2005-01-01

    Irreversible aggregation processes involving reactive and frozen clusters are investigated using the rate equation approach. In aggregation events, two clusters join irreversibly to form a larger cluster; additionally, reactive clusters may spontaneously freeze. Frozen clusters do not participate in merger events. Generally, freezing controls the nature of the aggregation process, as demonstrated by the final distribution of frozen clusters. The cluster mass distribution has a power-law tail, F k ∼k -γ , when the freezing process is sufficiently slow. Different exponents, γ = 1 and 3, are found for the constant and the product aggregation rates, respectively. For the latter case, the standard polymerization model, either no gels, or a single gel, or even multiple gels, may be produced

  2. Synthesis by plasma of halogenated poly anilines

    International Nuclear Information System (INIS)

    Enriquez, M.A.; Olayo, M.G.; Cruz, G.J.

    2002-01-01

    In this work polymerization by plasma of aniline with iodine and chlorine bonded chemically to the aniline ring were realized. The results of the synthesis and characterizations are compared with those ones obtained starting from the poly aniline synthesis (P An) doped with iodine, where the dopant was aggregated in the moment of the polymerization. The objective is to study the dopant behavior in the synthesis by plasma in function of the properties of these polymers. (Author)

  3. Polymeric micelles for drug targeting.

    Science.gov (United States)

    Mahmud, Abdullah; Xiong, Xiao-Bing; Aliabadi, Hamidreza Montazeri; Lavasanifar, Afsaneh

    2007-11-01

    Polymeric micelles are nano-delivery systems formed through self-assembly of amphiphilic block copolymers in an aqueous environment. The nanoscopic dimension, stealth properties induced by the hydrophilic polymeric brush on the micellar surface, capacity for stabilized encapsulation of hydrophobic drugs offered by the hydrophobic and rigid micellar core, and finally a possibility for the chemical manipulation of the core/shell structure have made polymeric micelles one of the most promising carriers for drug targeting. To date, three generations of polymeric micellar delivery systems, i.e. polymeric micelles for passive, active and multifunctional drug targeting, have arisen from research efforts, with each subsequent generation displaying greater specificity for the diseased tissue and/or targeting efficiency. The present manuscript aims to review the research efforts made for the development of each generation and provide an assessment on the overall success of polymeric micellar delivery system in drug targeting. The emphasis is placed on the design and development of ligand modified, stimuli responsive and multifunctional polymeric micelles for drug targeting.

  4. Pyrolysis of methane in flowing microwave plasma. Pt. 1, 2

    International Nuclear Information System (INIS)

    Carmi, U.; Inor, A.A.; Avni, R.; Nickel, H.

    1978-04-01

    The flowing microwave (2.45 G Hz) plasmas of methane and methane-argon mixtures were analyzed by the electrical double floating probe system (DFPS), along the flow stream. The measured electric variables of the microwave plasma were: current, current density, electric field strength, electron temperature, positive ion and electron concentrations. They indicate an irreversible process, of the polymerization of CH 4 and CH 4 +Ar mixtures, taking place in the plasma. The polymerization process reaches its maximum 'down stream'. after the position of the microwave cavity. The polymerization was correlated to the concentration of ions and electrons in the plasma. (orig.) [de

  5. Scintigraphic evaluation of the pharmacokinetics of a soluble polymeric drug carrier

    International Nuclear Information System (INIS)

    Pimm, M.V.; Perkins, A.C.; Hudecz, F.

    1992-01-01

    There is a growing interest in the use of macromolecular carriers for therapeutic agents. If these carriers can be labelled with an appropriate gamma-emitter, their biodistribution could be followed by scintigraphy. We have imaged the biodistribution of a synthetic branched polypeptide, based on a poly-L-lysine backbone (average molecular mass 45 kDa). The polymer was conjugated to diethylene triamine penta-acetic acid and labelled by chelation with indium-111. Mice were injected i.v. with labelled material and imaged with a gamma-camera with a pin-hole collimator. Images showed the majority of tracer remaining in the blood pool, but about 35% appeared in the urinary bladder within 1.5 h. When the 111 In-polymer was fractionated by gel filtration chromatography on S-300, the imaging showed that the early eluting material was retained, the intermediate showed some renal clearance, and the late was rapidly excreted. These findings show the value of gamma-scintigraphy for biodistribution studies with such polymeric drug carriers and its potential for clinical pharmacokinetic studies. (orig.)

  6. Organometallic Polymeric Conductors

    Science.gov (United States)

    Youngs, Wiley J.

    1997-01-01

    For aerospace applications, the use of polymers can result in tremendous weight savings over metals. Suitable polymeric materials for some applications like EMI shielding, spacecraft grounding, and charge dissipation must combine high electrical conductivity with long-term environmental stability, good processability, and good mechanical properties. Recently, other investigators have reported hybrid films made from an electrically conductive polymer combined with insulating polymers. In all of these instances, the films were prepared by infiltrating an insulating polymer with a precursor for a conductive polymer (either polypyrrole or polythiophene), and oxidatively polymerizing the precursor in situ. The resulting composite films have good electrical conductivity, while overcoming the brittleness inherent in most conductive polymers. Many aerospace applications require a combination of properties. Thus, hybrid films made from polyimides or other engineering resins are of primary interest, but only if conductivities on the same order as those obtained with a polystyrene base could be obtained. Hence, a series of experiments was performed to optimize the conductivity of polyimide-based composite films. The polyimide base chosen for this study was Kapton. 3-MethylThiophene (3MT) was used for the conductive phase. Three processing variables were identified for producing these composite films, namely time, temperature, and oxidant concentration for the in situ oxidation. Statistically designed experiments were used to examine the effects of these variables and synergistic/interactive effects among variables on the electrical conductivity and mechanical strength of the films. Multiple linear regression analysis of the tensile data revealed that temperature and time have the greatest effect on maximum stress. The response surface of maximum stress vs. temperature and time (for oxidant concentration at 1.2 M) is shown. Conductivity of the composite films was measured for

  7. De fysica van polymere materialen

    NARCIS (Netherlands)

    Struik, L.C.E.

    1987-01-01

    Rede, uitgesproken ter gelegenheid van de aanvaarding van het ambt van buitengewoon hoogleraar in de fysica van polymere materialen aan de Universitelt Twente op donderdag 22 januarì 1987 door Dr.lr. L.C.E. Struik.

  8. Phosphazene-promoted anionic polymerization

    KAUST Repository

    Zhao, Junpeng; Hadjichristidis, Nikolaos; Gnanou, Yves

    2014-01-01

    .e. in situ activation (of initiating sites) and polymerization, and summarize the applications of such a mechanism on macromolecular engineering toward functionalized polymers, block copolymers and complex macromolecular architectures.

  9. Schlenk Techniques for Anionic Polymerization

    KAUST Repository

    Ratkanthwar, Kedar; Zhao, Junpeng; Zhang, Hefeng; Hadjichristidis, Nikolaos; Mays, Jimmy

    2015-01-01

    Anionic polymerization-high vacuum techniques (HVTs) are doubtlessly the most prominent and reliable experimental tools to prepare polymer samples with well-defined and, in many cases, complex macromolecular architectures. Due to the high demands

  10. Pulsed-laser polymerization in compartmentalized liquids. 1. Polymerization in vesicles

    NARCIS (Netherlands)

    Jung, M.; Casteren, van I.A.; Monteiro, M.J.; Herk, van A.M.; German, A.L.

    2000-01-01

    Polymerization in vesicles is a novel type of polymerization in heterogeneous media, leading to parachute-like vesicle-polymer hybrid morphologies. To explore the kinetics of vesicle polymerizations and to learn more about the actual locus of polymerization we applied the pulsed-laser polymerization

  11. The value of dynamic renal 99Tcm-diethylene triamine penta acetic acid imaging in rabbits with acute upper urinary tract obstruction

    International Nuclear Information System (INIS)

    Yan Jun; Li Xianfeng; Wang Jin; Li Sijin; Liu Jianzhong; Cheng Yan; Wu Zhifeng

    2008-01-01

    Objective: To research the degression of renal function of 99 Tc m -diethylene triamine pentaaceticacid ( 99 Tc m -DTPA) renal imaging in rabbits with acute upper urinary tract obstruction and its early recovery after relief. Methods: Twenty-four health rabbit models with left acute upper urinary tract obstruction were built up. 99 Tc m -DTPA renal imaging was performed before making model and after obstruction 1, 3, 5-7 and more than 8 weeks respectively and 4 weeks after relief of obstruction. Results: After obstnrction 1 and 3 weeks, 99 Tc m -DTPA imaging showed development in left renal. Values of glomemlar filtration rate (GFR) and uptake ratio decreased, while time to reach the peak increased. These are obviously different compared with those before obstruction (t=2.916, t=7.034, P 99 Tc m -DTPA imagingshowed cortex developert. Values of GFR and uptake ratio decreased obvious, while time to reach the peak increased obviously. These are obviously different compared with those before obstruction (t=6.722, t=7.470, t=3.678, P 99 Tc m -DTPA imaging showed no obvious development. In those rabbits with durations of 1-3 weeks obstructions, the renal function could almost recover within 4 weeks after relief of obstruction. GRF is 31.23 ± 14.4 (t=2.627, P 0.05). With obstruction of 5-7 weeks, the GRF and uptake ratio, could recover partly to some extent. But with obstruction for more than 8 weeks, the renal function could not recover. Conclusions: For the acute upper urinary tract obstruction, the renal function is most remarkable decreased in the early time, and can be restored after lelief. For long time obstruction, even if relieved, the renal function is not easily to restore. The dynamic renal imaging can reflect the extent of the renal damage and its recovery, and could be used as a reliable indicator. (authors)

  12. Deposition of aqueous aerosol of technetium-99m diethylene triamine penta-acetic acid generated and delivered by a novel system (AERx) in healthy subjects

    International Nuclear Information System (INIS)

    Chan, H.K.; Eberl, S.; Bautovich, G.

    1999-01-01

    Deposition of technetium-99m diethylene triamine penta-acetic acid aqueous radioaerosols generated by a novel aerosol delivery system (AER x ) was studied in six healthy subjects using both planar and single-photon emission tomography (SPET) imaging. AER x is a microprocessor-controlled, bolus inhalation device that is actuated at pre-programmed values of inspiratory flow rate and volume. The aims of the study were to determine the effects of posture and inhaled volume upon deposition of the aerosol in the lungs. Each subject inhaled the radioaerosol in two positions (supine vs sitting) and with two inspiratory manoeuvres [vital capacity (VC) vs ''fixed volume'' of 1 l above functional residual capacity]. Simultaneous transmission-emission planar and tomographic images were acquired. The results showed diffuse deposition of the aerosol in the lung. Neither the breathing manoeuvre nor the posture was found to affect the distribution of the aerosol as measured by the ratio of the activity (counts per pixel) in the peripheral:central (penetration index, PI) or in the apex:base regions of the planar lung images (P>0.1). A small, albeit statistically significant, difference in PI (P x system showed high efficiency of delivery, with approximately 50% of the extruded dose in the device depositing in the lung. The uniformity of radioactivity distributed throughout the lung is attributed to the fine particle size (mass median aerodynamic diameter of 2 μm) of the aerosol and the electronic control of aerosol inhalation by the device. In conclusion, the AER x system can be ideal for diffuse aerosol deposition of therapeutic or diagnostic agents and is largely unaffected by inhaled volume and posture. The efficiency of the device device can limit the total radiation exposure of patients and staff administering the radioaerosols, and can make it suitable for delivery of expensive drugs. (orig.)

  13. Polyolefin nanocomposites in situ polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Galland, Griselda Barrera; Fim, Fabiana de C.; Milani, Marceo A.; Silva, Silene P. da; Forest, Tadeu; Radaelli, Gislaine, E-mail: griselda.barrera@ufrgs.br [Universidade Federal do Rio Grande de Sul - UFRGS, Porto Alegre, RS (Brazil); Basso, Nara R.S. [Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil); Quijada, Raul [Universidad de Chile, Santiago (Chile)

    2011-07-01

    Polyethylene and polypropylene nanocomposites using grapheme nanosheets and treated chrysotile have been synthesized by in situ polymerization using metallocene catalysts. The fillers have been submitted to acid, thermal and/ou ultrasound treatments before to introduce them into the polymerization reactor. A complete characterization of the fillers has been done. The nanocomposites have been characterized by SEM, TEM, DRX and AFM. The thermal, mechanic -dynamic, mechanical and electrical properties of the nanocomposites are discussed. (author)

  14. Polyolefin nanocomposites in situ polymerization

    International Nuclear Information System (INIS)

    Galland, Griselda Barrera; Fim, Fabiana de C.; Milani, Marceo A.; Silva, Silene P. da; Forest, Tadeu; Radaelli, Gislaine; Basso, Nara R.S.; Quijada, Raul

    2011-01-01

    Polyethylene and polypropylene nanocomposites using grapheme nanosheets and treated chrysotile have been synthesized by in situ polymerization using metallocene catalysts. The fillers have been submitted to acid, thermal and/ou ultrasound treatments before to introduce them into the polymerization reactor. A complete characterization of the fillers has been done. The nanocomposites have been characterized by SEM, TEM, DRX and AFM. The thermal, mechanic -dynamic, mechanical and electrical properties of the nanocomposites are discussed. (author)

  15. Electroactivity in Polymeric Materials

    CERN Document Server

    2012-01-01

    Electroactivity in Polymeric Materials provides an in-depth view of the theory of electroactivity and explores exactly how and why various electroactive phenomena occur. The book explains the theory behind electroactive bending (including ion-polymer-metal-composites –IPMCs), dielectric elastomers, electroactive contraction, and electroactive contraction-expansion cycles.  The book also balances theory with applications – how electroactivity can be used – drawing inspiration from the manmade mechanical world and the natural world around us.  This book captures: A complete introduction to electroactive materials including examples and recent developments The theory and applications of numerous topics like electroactive bending of dielectric elastomers and electroactive contraction and expansion New topics, such as biomimetic applications and energy harvesting This is a must-read within the electroactive community, particularly for professionals and graduate students who are interested in the ...

  16. Mechanical reliability of porous low-k dielectrics for advanced interconnect: Study of the instability mechanisms in porous low-k dielectrics and their mediation through inert plasma induced re-polymerization of the backbone structure

    Science.gov (United States)

    Sa, Yoonki

    Continuous scaling down of critical dimensions in interconnect structures requires the use of ultralow dielectric constant (k) films as interlayer dielectrics to reduce resistance-capacitance delays. Porous carbon-doped silicon oxide (p-SiCOH) dielectrics have been the leading approach to produce these ultralow-k materials. However, embedding of porosity into dielectric layer necessarily decreases the mechanical reliability and increases its susceptibility to adsorption of potentially deleterious chemical species during device fabrication process. Among those, exposure of porous-SiCOH low-k (PLK) dielectrics to oxidizing plasma environment causes the increase in dielectric constant and their vulnerability to mechanical instability of PLKs due to the loss of methyl species and increase in moisture uptake. These changes in PLK properties and physical stability have been persisting challenges for next-generation interconnects because they are the sources of failure in interconnect integration as well as functional and physical failures appearing later in IC device manufacturing. It is therefore essential to study the fundamentals of the interactions on p-SiCOH matrix induced by plasma exposure and find an effective and easy-to-implement way to reverse such changes by repairing damage in PLK structure. From these perspectives, the present dissertation proposes 1) a fundamental understanding of structural transformation occurring during oxidative plasma exposure in PLK matrix structure and 2) its restoration by using silylating treatment, soft x-ray and inert Ar-plasma radiation, respectively. Equally important, 3) as an alternative way of increasing the thermo-mechanical reliability, PLK dielectric film with an intrinsically robust structure by controlling pore morphology is fabricated and investigated. Based on the investigations, stability of PLK films studied by time-dependent ball indentation tester under the elevated temperature, variation in film thickness and

  17. In search of a consensus terminology in the field of platelet concentrates for surgical use: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), fibrin gel polymerization and leukocytes.

    Science.gov (United States)

    Dohan Ehrenfest, David M; Bielecki, Tomasz; Mishra, Allan; Borzini, Piero; Inchingolo, Francesco; Sammartino, Gilberto; Rasmusson, Lars; Everts, Peter A

    2012-06-01

    In the field of platelet concentrates for surgical use, most products are termed Platelet-Rich Plasma (PRP). Unfortunately, this term is very general and incomplete, leading to many confusions in the scientific database. In this article, a panel of experts discusses this issue and proposes an accurate and simple terminology system for platelet concentrates for surgical use. Four main categories of products can be easily defined, depending on their leukocyte content and fibrin architecture: Pure Platelet-Rich Plasma (P-PRP), such as cell separator PRP, Vivostat PRF or Anitua's PRGF; Leukocyteand Platelet-Rich Plasma (L-PRP), such as Curasan, Regen, Plateltex, SmartPReP, PCCS, Magellan, Angel or GPS PRP; Pure Plaletet-Rich Fibrin (P-PRF), such as Fibrinet; and Leukocyte- and Platelet-Rich Fibrin (L-PRF), such as Choukroun's PRF. P-PRP and L-PRP refer to the unactivated liquid form of these products, their activated versions being respectively named P-PRP gels and L-PRP gels. The purpose of this search for a terminology consensus is to plead for a more serious characterization of these products. Researchers have to be aware of the complex nature of these living biomaterials, in order to avoid misunderstandings and erroneous conclusions. Understanding the biomaterials or believing in the magic of growth factors ? From this choice depends the future of the field.

  18. Synthesis by plasma of halogenated poly anilines; Sintesis por plasma de polianilinas halogenadas

    Energy Technology Data Exchange (ETDEWEB)

    Enriquez, M.A.; Olayo, M.G.; Cruz, G.J. [Facultad de Quimica, UAEM, 50000 Toluca, Estado de Mexico (Mexico)

    2002-07-01

    In this work polymerization by plasma of aniline with iodine and chlorine bonded chemically to the aniline ring were realized. The results of the synthesis and characterizations are compared with those ones obtained starting from the poly aniline synthesis (P An) doped with iodine, where the dopant was aggregated in the moment of the polymerization. The objective is to study the dopant behavior in the synthesis by plasma in function of the properties of these polymers. (Author)

  19. Fast preparation of hybrid monolithic columns via photo-initiated thiol-yne polymerization for capillary liquid chromatography.

    Science.gov (United States)

    Ma, Shujuan; Zhang, Haiyang; Li, Ya; Li, Yanan; Zhang, Na; Ou, Junjie; Ye, Mingliang; Wei, Yinmao

    2018-02-23

    Although several approaches have been developed to fabricate hybrid monoliths, it would still take a few hours to finish the formation of monoliths. Herein, photo-initiated thiol-yne polymerization was first adopted to in situ fabricate hybrid monoliths within the confines of UV-transparent fused-silica capillary. A silicon-containing diyne (1,3-diethynyltetramethyl-disiloxane, DYDS) was copolymerized with three multithiols, 1,6-hexanedithiol, trimethylolpropane tris(3-mercaptopropionate) and pentaerythriol tetrakis(3-mercaptopropionate), by using a binary porogenic system of diethylene glycol diethyl ether (DEGDE)/poly(ethylene glycol) (PEG200) within 10 min. Several characterizations of three hybrid monoliths (assigned as I, II and III, respectively) were performed. The results showed that these hybrid monoliths possessed bicontinuous porous structure, which was remarkably different from that via typical free-radical polymerization. The highest column efficiency of 76,000 plates per meter for butylbenzene was obtained on the column I in reversed-phase liquid chromatography (RPLC). It was observed that the efficiencies for strong-retained butylbenzene were almost close to those of weak-retained benzene, indicating a retention-independent efficient performance of small molecules on hybrid column I. The surface area of this hybrid monolith was very small in the dry state (less than 10.0 m 2 /g), and the chromatographic behavior of hybrid monolithic columns would be possibly explained by radical-mediated step-growth process of thiol-yne polymerization. Finally, the column I was applied for separation of BSA tryptic digest by cLC-MS/MS, indicating satisfactory separation ability for complicated samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Ablation and formation by plasma of silver metallic films on poly aniline; Ablacion y formacion por plasma de peliculas metalicas de plata sobre polianilina

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, J.C.; Olayo, G.; Morales, J.; Cruz, G.J. [Posgrado en Materiales, Facultad de Quimica, UAEM, Paseo Colon esq. Tollocan, Toluca, Estado de Mexico, C.P. 50000 (Mexico)

    2000-07-01

    This work shows a study about the ablation by plasma conditions in which is possible to form silver layers over polymeric surfaces with the purpose to increase the electric conductivity of the surface. The adhesion between layers formed by polymerization and ablation by plasma respectively is high, with this it is possible to find adequate conditions for getting the polymerization and ablation simultaneously forming with this a thin polymer matrix which would have metallic elements dispersed in its structure. (Author)

  1. Polyethylene-waste tire dust composites via in situ polymerization

    International Nuclear Information System (INIS)

    Reyes A, Y. K.; Narro C, R. I.; Ramos A, M. E.; Neira V, M. G.; Diaz E, J.; Enriquez M, F.; Valencia L, L. A.; Saade C, H.; Diaz de L, R.

    2014-01-01

    Polyethylene/waste tire dust (WTD) composites were obtained by an in situ polymerization technique. The surface of the WTD was modified with deposition of polyethylene by using plasma polymerization. Ethylene polymerization was carried out using bis(cyclopentadienyl) titanium dichloride (Cp 2 TiCl 2 ) as homogeneous metallocenes catalyst, while diethylaluminum chloride (DEAC), ethyl aluminum sesquichloride (EASC) and methyl alumino xane (Mao) were used as co-catalysts at two different [Al]/[Ti] molar ratio. The main characteristics of the obtained polyethylenes were determined by size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry and wide-angle X-ray diffraction. The results showed that by using EASC and Mao the highest catalytic activities were presented at a [Al]/[Ti] molar ratio of 9.17 and 18.33 respectively. Even though it was possible to obtain polyethylene using WTD (modified or unmodified) the catalytic activity was lower than in the case in which no WTD was added in ethylene polymerization. Scanning transmission electronic microscopy images evidenced that the original morphology of the polyethylenes was not modified by the presence of WTD. (Author)

  2. Polyethylene-waste tire dust composites via in situ polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Reyes A, Y. K.; Narro C, R. I.; Ramos A, M. E. [Universidad Autonoma de Coahuila, Facultad de Ciencias Quimicas, Blvd. Venustiano Carranza s/n, 25280 Saltillo, Coahuila (Mexico); Neira V, M. G.; Diaz E, J.; Enriquez M, F.; Valencia L, L. A.; Saade C, H.; Diaz de L, R., E-mail: ramon.diazdeleon@ciqa.edu.mx [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna Hermosillo No. 40, Col. San Jose de los Cerritos, 25293 Saltillo, Coahuila (Mexico)

    2014-10-01

    Polyethylene/waste tire dust (WTD) composites were obtained by an in situ polymerization technique. The surface of the WTD was modified with deposition of polyethylene by using plasma polymerization. Ethylene polymerization was carried out using bis(cyclopentadienyl) titanium dichloride (Cp{sub 2}TiCl{sub 2}) as homogeneous metallocenes catalyst, while diethylaluminum chloride (DEAC), ethyl aluminum sesquichloride (EASC) and methyl alumino xane (Mao) were used as co-catalysts at two different [Al]/[Ti] molar ratio. The main characteristics of the obtained polyethylenes were determined by size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry and wide-angle X-ray diffraction. The results showed that by using EASC and Mao the highest catalytic activities were presented at a [Al]/[Ti] molar ratio of 9.17 and 18.33 respectively. Even though it was possible to obtain polyethylene using WTD (modified or unmodified) the catalytic activity was lower than in the case in which no WTD was added in ethylene polymerization. Scanning transmission electronic microscopy images evidenced that the original morphology of the polyethylenes was not modified by the presence of WTD. (Author)

  3. Factors predicting aggressiveness of non-hypervascular hepatic nodules detected on hepatobiliary phase of gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid magnetic resonance imaging.

    Science.gov (United States)

    Kanefuji, Tsutomu; Takano, Toru; Suda, Takeshi; Akazawa, Kouhei; Yokoo, Takeshi; Kamimura, Hiroteru; Kamimura, Kenya; Tsuchiya, Atsunori; Takamura, Masaaki; Kawai, Hirokazu; Yamagiwa, Satoshi; Aoyama, Hidefumi; Nomoto, Minoru; Terai, Shuji

    2015-04-21

    To establish a prognostic formula that distinguishes non-hypervascular hepatic nodules (NHNs) with higher aggressiveness from less hazardous one. Seventy-three NHNs were detected in gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid magnetic resonance imaging (Gd-EOB-DTPA-MRI) study and confirmed to change 2 mm or more in size and/or to gain hypervascularity. All images were interpreted independently by an experienced, board-certified abdominal radiologist and hepatologist; both knew that the patients were at risk for hepatocellular carcinoma development but were blinded to the clinical information. A formula predicting NHN destiny was developed using a generalized estimating equation model with thirteen explanatory variables: age, gender, background liver diseases, Child-Pugh class, NHN diameter, T1-weighted imaging/T2-weighted imaging detectability, fat deposition, lower signal intensity in arterial phase, lower signal intensity in equilibrium phase, α-fetoprotein, des-γ-carboxy prothrombin, α-fetoprotein-L3, and coexistence of classical hepatocellular carcinoma. The accuracy of the formula was validated in bootstrap samples that were created by resampling of 1000 iterations. During a median follow-up period of 504 d, 73 NHNs with a median diameter of 9 mm (interquartile range: 8-12 mm) grew or shrank by 68.5% (fifty nodules) or 20.5% (fifteen nodules), respectively, whereas hypervascularity developed in 38.4% (twenty eight nodules). In the fifteen shrank nodules, twelve nodules disappeared, while 11.0% (eight nodules) were stable in size but acquired vascularity. A generalized estimating equation analysis selected five explanatories from the thirteen variables as significant factors to predict NHN progression. The estimated regression coefficients were 0.36 for age, 6.51 for lower signal intensity in arterial phase, 8.70 or 6.03 for positivity of hepatitis B virus or hepatitis C virus, 9.37 for des-γ-carboxy prothrombin, and -4.05 for fat

  4. Polymeric media for tritium fixation

    International Nuclear Information System (INIS)

    Franz, J.A.; Burger, L.L.

    1975-01-01

    The synthesis and leach testing of several polymeric media for tritium fixation are presented. Tritiated bakelite, poly(acrylonitrile) and polystyrene successfully fixed tritium. Tritium leach rates at the tracer level appear to be negligible. Advantages and disadvantages of the processes are discussed, and further bench-scale investigations underway are reported. Rough cost estimates are presented for the different media and are compared with alternate approaches such as deep-well injection and long-term tank storage. Polymeric media costs are high compared to deep-well storage and are of the same order of magnitude per liter of water as for isotopic enrichment. With this limitation, polymeric media can be economically feasible only for highly concentrated tritiated wastes. It is recommended that the bakelite and polystyrene processes be examined on a larger scale to permit more accurate cost analysis and process design. (auth)

  5. Olefin metathesis and metathesis polymerization

    CERN Document Server

    Ivin, K J

    1997-01-01

    This book is a follow-up to Ivins Olefin Metathesis, (Academic Press, 1983). Bringing the standard text in the field up to date, this Second Edition is a result of rapid growth in the field, sparked by the discovery of numerous well-defined metal carbene complexes that can act as very efficient initiators of all types of olefin metathesis reaction, including ring-closing metathesis of acyclic dienes, enynes, and dienynes; ring-opening metathesis polymerizationof cycloalkenes, acyclic diene metathesis polymerization; and polymerization of alkynes, as well as simple olefin metathesis. Olefin Metathesis and Metathesis Polymerization provides a broad, up-to-date account of the subject from its beginnings in 1957 to the latest applications in organic synthesis. The book follows the same format as the original, making it useful toteachers and to researchers, and will be of particular interest to those working in the fields of organic chemistry, polymer chemistry, organometallic chemistry, catalysis, materials scien...

  6. On-demand photoinitiated polymerization

    Science.gov (United States)

    Boydston, Andrew J; Grubbs, Robert H; Daeffler, Chris; Momcilovic, Nebojsa

    2013-12-10

    Compositions and methods for adjustable lenses are provided. In some embodiments, the lenses contain a lens matrix material, a masking compound, and a prepolymer. The lens matrix material provides structure to the lens. The masking compound is capable of blocking polymerization or crosslinking of the prepolymer, until photoisomerization of the compound is triggered, and the compound is converted from a first isomer to a second isomer having a different absorption profile. The prepolymer is a composition that can undergo a polymerization or crosslinking reaction upon photoinitiation to alter one or more of the properties of the lenses.

  7. Pentafluorosulfanyl Substituents in Polymerization Catalysis.

    Science.gov (United States)

    Kenyon, Philip; Mecking, Stefan

    2017-10-04

    Highly electron-withdrawing pentafluorosulfanyl groups were probed as substituents in an organometallic catalyst. In Ni(II) salicylaldiminato complexes as an example case, these highly electron-withdrawing substituents allow for polymerization of ethylene to higher molecular weights with reduced branching due to significant reductions in β-hydrogen elimination. Combined with the excellent functional group tolerance of neutral Ni(II) complexes, this suppression of β-hydrogen elimination allows for the direct polymerization of ethylene in water to nanocrystal dispersions of disentangled, ultrahigh-molecular-weight linear polyethylene.

  8. Radiation Induced Polymerization of Pyrrole

    International Nuclear Information System (INIS)

    Sarada Idris; Ratnam, C.T.; Ahmad Ashrif Abu Bakar

    2016-01-01

    We demonstrate the polymerization of pyrrole by gamma irradiation. The pyrrole films were exposed to gamma ray from cobalt 60 source at doses ranging from 0 to 150 kGy. The films were subjected to structural and morphological analyses by using FTIR, SEM and AFM techniques. Similar studies were also made on pristine pyrrole film which serve as control. Results revealed that pyrrole has been successfully polymerized through irradiation induced reactions. The SEM images depicted the formation of cauliflower shape upon gamma irradiation. The structural changes of pyrrole also evidenced by FTIR spectra. Surface topography and roughness of pyrrole before and after gamma irradiation found to show significant differences. (author)

  9. Functionalization and Polymerization on the CNT Surfaces

    KAUST Repository

    Albuerne, Julio

    2013-07-01

    In this review we focus on the current status of using carbon nanotube (CNT) as a filler for polymer nanocomposites. Starting with the historical background of CNT, its distinct properties and the surface functionalization of the nanotube, the three different surface polymerization techniques, namely grafting "from", "to" and "through/in between" were discussed. Wider focus has been given on "grafting from" surface initiated polymerizations, including atom transfer radical polymerization (ATRP), reversible addition fragmentation chain-transfer (RAFT) Polymerization, nitroxide mediated polymerization (NMP), ring opening polymerization (ROP) and other miscellaneous polymerization methods. The grafting "to" and "through / in between" also discussed and compared with grafting from polymerization. The merits and shortcomings of all three grafting methods were discussed and the bottleneck issue in grafting from method has been highlighted. Furthermore the current and potential future industrial applications were deliberated. Finally the toxicity issue of CNTs in the final product has been reviewed with the limited available literature knowledge. © 2013 Bentham Science Publishers.

  10. High Vacuum Techniques for Anionic Polymerization

    KAUST Repository

    Ratkanthwar, Kedar; Hadjichristidis, Nikolaos; Mays, Jimmy

    2015-01-01

    Anionic polymerization high vacuum techniques (HVTs) are the most suitable for the preparation of polymer samples with well-defined complex macromolecular architectures. Though HVTs require glassblowing skill for designing and making polymerization

  11. Surface modification of polypropylene membrane by polyethylene glycol graft polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Abednejad, Atiye Sadat, E-mail: atiyeabednejad@gmail.com [Department of Biomedical Engineering, Faculty of New Sciences and Technologies, University of Tehran, P.O. Box 14395-1561, Tehran (Iran, Islamic Republic of); Amoabediny, Ghasem [Department of Life Science Engineering, Faculty of New Sciences and Technologies, University of Tehran, P.O. Box 14395-1561, Tehran (Iran, Islamic Republic of); Research Center for New Technologies in Life Science Engineering, University of Tehran, P.O. Box 63894-14179, Tehran (Iran, Islamic Republic of); Ghaee, Azadeh [Department of Biomedical Engineering, Faculty of New Sciences and Technologies, University of Tehran, P.O. Box 14395-1561, Tehran (Iran, Islamic Republic of)

    2014-09-01

    Polypropylene hollow fiber microporous membranes have been used in a wide range of applications, including blood oxygenator. The hydrophobic feature of the polypropylene surface causes membrane fouling. To minimize fouling, a modification consisting of three steps: surface activation in H{sub 2} and O{sub 2} plasma, membrane immersion in polyethylene glycol (PEG) and plasma graft polymerization was performed. The membranes were characterized by contact angle measurement, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), tensile test, scanning electron microscopy (SEM) and atomic force microscopy (AFM). Oxygen transfer of modified membranes was also tested. The stability of grafted PEG was measured in water and in phosphate buffer saline (PBS) at 37 °C. Blood compatibility of modified surfaces was evaluated by the platelet adhesion method. Water contact angel reduction from 110° to 72° demonstrates the enhanced hydrophilicity, and XPS results verify the presence of oxygenated functional groups due to the peak existence in 286 eV as a result of PEG grafting. The results clearly indicate that plasma graft-polymerization of PEG is an effective way for antifouling improvement of polypropylene membranes. Also, the results show that oxygen transfer changes in PEG grafted membranes are not significant. - Highlights: • H{sub 2} and O{sub 2} plasma graft polymerization of PEG on polypropylene membrane was carried out. • Changes in surface properties were investigated by FTIR, XPS, SEM, and AFM. • Surface wettability enhanced as a result of poly ethylene glycol grafting. • PEG grafting degree increase causes reduction of fouling and adhesion.

  12. Ablation and formation by plasma of silver metallic films on poly aniline

    International Nuclear Information System (INIS)

    Palacios, J.C.; Olayo, G.; Morales, J.; Cruz, G.J.

    1999-01-01

    This work shows a study about the ablation by plasma conditions in which is possible to form silver layers over polymeric surfaces with the purpose to increase the electric conductivity of the surface. The adhesion between layers formed by polymerization and ablation by plasma respectively is high, with this it is possible to find adequate conditions for getting the polymerization and ablation simultaneously forming with this a thin polymer matrix which would have metallic elements dispersed in its structure. (Author)

  13. Novel polymeric materials from triglycerides

    Science.gov (United States)

    Triglycerides are good platforms for new polymeric products that can substitute for petroleum-based materials. As part of our research emphasis in sustainability and green polymer chemistry, we have explored a number of reactions in efforts to produce a wide range of value-added products. In this ...

  14. Novel solid state polymeric batteries

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, A.; Glasse, M.; Latham, R.; Linford, R.

    1986-01-01

    AC conductivity measurements have been performed on a number of polymeric electrolytes containing Mg, Ca, Sr and Zn perchlorates and Mg and Ca thiocyanates. The electrolytes were characterized using DSC. Results are reported of preliminary tests of cells incorporating anodes of the above metals. 11 refs.

  15. Reactive surfactants in heterophase polymerization

    NARCIS (Netherlands)

    Guyot, A.; Tauer, K.; Asua, J.M.; Es, van J.J.G.S.; Gauthier, C.; Hellgren, A.C.; Sherrington, D.C.; Montoya-Goni, A.; Sjöberg, M.; Sindt, O.; Vidal, F.F.M.; Unzue, M.; Schoonbrood, H.A.S.; Schipper, E.T.W.M.; Lacroix-Desmazes, P.

    1999-01-01

    This paper summarizes the work carried out during 3 years in a Network of the program "Human Capital and Mobility" of the European Union CHRX 93-0159 entitled "Reactive surfactants in heterophase polymerization for high performance polymers". A series of about 25 original papers will be published in

  16. Biodegradable polymeric prodrugs of naltrexone

    NARCIS (Netherlands)

    Bennet, D.B.; Li, X.; Adams, N.W.; Kim, S.W.; Hoes, C.J.T.; Hoes, C.J.T.; Feijen, Jan

    1991-01-01

    The development of a biodegradable polymeric drug delivery system for the narcotic antagonist naltrexone may improve patient compliance in the treatment of opiate addiction. Random copolymers consisting of the ¿-amino acids N5-(3-hydroxypropyl--glutamine and -leucine were synthesized with equimolar

  17. Preparations of spherical polymeric particles from Tanzanian ...

    African Journals Online (AJOL)

    Spherical Polymeric Particles (SPP) have been prepared from Tanzanian Cashew Nut Shell Liquid (CNSL) by suspension polymerization technique involving either step-growth or chain- growth polymerization mechanisms. The sizes of the SPP, which ranged from 0.1 to 2.0 mm were strongly influenced by the amounts of ...

  18. Apparatus and method for stabilization or oxidation of polymeric materials

    Science.gov (United States)

    Paulauskas, Felix L [Knoxville, TN; Sherman, Daniel M [Knoxville, TN

    2010-01-19

    An apparatus for treating polymeric materials comprises a treatment chamber adapted to maintain a selected atmosphere at a selected temperature; a means for supporting the polymeric material within the chamber; and, a source of ozone-containing gas, which decomposes at the selected temperature yielding at least one reactive oxidative species whereby the polymer is stabilized and cross linked through exposure to the oxidative species in the chamber at the selected temperature. The ozone may be generated by a plasma discharge or by various chemical processes. The apparatus may be configured for either batch-type or continuous-type processing. The apparatus and method are especially useful for preparing polymer fibers, particularly PAN fibers, for later carbonization treatments as well as to make flame-retardant fabrics.

  19. Antimicrobial activity of silver nanoparticles encapsulated in poly-N-isopropylacrylamide-based polymeric nanoparticles.

    Science.gov (United States)

    Qasim, Muhammad; Udomluck, Nopphadol; Chang, Jihyun; Park, Hansoo; Kim, Kyobum

    2018-01-01

    In this study, we analyzed the antimicrobial activities of poly- N -isopropylacrylamide (pNIPAM)-based polymeric nanoparticles encapsulating silver nanoparticles (AgNPs). Three sizes of AgNP-encapsulating pNIPAM- and pNIPAM-NH 2 -based polymeric nanoparticles were fabricated. Highly stable and uniformly distributed AgNPs were encapsulated within polymeric nanoparticles via in situ reduction of AgNO 3 using NaBH 4 as the reducing agent. The formation and distribution of AgNPs was confirmed by UV-visible spectroscopy, transmission electron microscopy, and inductively coupled plasma optical emission spectrometry, respectively. Both polymeric nanoparticles showed significant bacteriostatic activities against Gram-negative ( Escherichia coli ) and Gram-positive ( Staphylococcus aureus ) bacteria depending on the nanoparticle size and amount of AgNO 3 used during fabrication.

  20. Dynamic bioactive stimuli-responsive polymeric surfaces

    Science.gov (United States)

    Pearson, Heather Marie

    This dissertation focuses on the design, synthesis, and development of antimicrobial and anticoagulant surfaces of polyethylene (PE), polypropylene (PP), and poly(tetrafluoroethylene) (PTFE) polymers. Aliphatic polymeric surfaces of PE and PP polymers functionalized using click chemistry reactions by the attachment of --COOH groups via microwave plasma reactions followed by functionalization with alkyne moieties. Azide containing ampicillin (AMP) was synthesized and subsequently clicked into the alkyne prepared PE and PP surfaces. Compared to non-functionalized PP and PE surfaces, the AMP clicked surfaces exhibited substantially enhanced antimicrobial activity against Staphylococcus aureus bacteria. To expand the biocompatibility of polymeric surface anticoagulant attributes, PE and PTFE surfaces were functionalized with pH-responsive poly(2-vinyl pyridine) (P2VP) and poly(acrylic acid) (PAA) polyelectrolyte tethers terminated with NH2 and COOH groups. The goal of these studies was to develop switchable stimuli-responsive polymeric surfaces that interact with biological environments and display simultaneous antimicrobial and anticoagulant properties. Antimicrobial AMP was covalently attached to --COOH terminal ends of protected PAA, while anticoagulant heparin (HEP) was attached to terminal --NH2 groups of P2VP. When pH 5.5, they collapse while the PAA segments extend. Such surfaces, when exposed to Staphylococcus aureus, inhibit bacterial growth due to the presence of AMP, as well as are effective anticoagulants due to the presence of covalently attached HEP. Comparison of these "dynamic" pH responsive surfaces with "static" surfaces terminated with AMP entities show significant enhancement of longevity and surface activity against microbial film formation. The last portion of this dissertation focuses on the covalent attachment of living T1 and Φ11 bacteriophages (phages) on PE and PTFE surface. This was accomplished by carbodiimide coupling between --COOH

  1. Glycine Polymerization on Oxide Minerals

    Science.gov (United States)

    Kitadai, Norio; Oonishi, Hiroyuki; Umemoto, Koichiro; Usui, Tomohiro; Fukushi, Keisuke; Nakashima, Satoru

    2017-06-01

    It has long been suggested that mineral surfaces played an important role in peptide bond formation on the primitive Earth. However, it remains unclear which mineral species was key to the prebiotic processes. This is because great discrepancies exist among the reported catalytic efficiencies of minerals for amino acid polymerizations, owing to mutually different experimental conditions. This study examined polymerization of glycine (Gly) on nine oxide minerals (amorphous silica, quartz, α-alumina and γ-alumina, anatase, rutile, hematite, magnetite, and forsterite) using identical preparation, heating, and analytical procedures. Results showed that a rutile surface is the most effective site for Gly polymerization in terms of both amounts and lengths of Gly polymers synthesized. The catalytic efficiency decreased as rutile > anatase > γ-alumina > forsterite > α- alumina > magnetite > hematite > quartz > amorphous silica. Based on reported molecular-level information for adsorption of Gly on these minerals, polymerization activation was inferred to have arisen from deprotonation of the NH3 + group of adsorbed Gly to the nucleophilic NH2 group, and from withdrawal of electron density from the carboxyl carbon to the surface metal ions. The orientation of adsorbed Gly on minerals is also a factor influencing the Gly reactivity. The examination of Gly-mineral interactions under identical experimental conditions has enabled the direct comparison of various minerals' catalytic efficiencies and has made discussion of polymerization mechanisms and their relative influences possible Further systematic investigations using the approach reported herein (which are expected to be fruitful) combined with future microscopic surface analyses will elucidate the role of minerals in the process of abiotic peptide bond formation.

  2. Glycine Polymerization on Oxide Minerals.

    Science.gov (United States)

    Kitadai, Norio; Oonishi, Hiroyuki; Umemoto, Koichiro; Usui, Tomohiro; Fukushi, Keisuke; Nakashima, Satoru

    2017-06-01

    It has long been suggested that mineral surfaces played an important role in peptide bond formation on the primitive Earth. However, it remains unclear which mineral species was key to the prebiotic processes. This is because great discrepancies exist among the reported catalytic efficiencies of minerals for amino acid polymerizations, owing to mutually different experimental conditions. This study examined polymerization of glycine (Gly) on nine oxide minerals (amorphous silica, quartz, α-alumina and γ-alumina, anatase, rutile, hematite, magnetite, and forsterite) using identical preparation, heating, and analytical procedures. Results showed that a rutile surface is the most effective site for Gly polymerization in terms of both amounts and lengths of Gly polymers synthesized. The catalytic efficiency decreased as rutile > anatase > γ-alumina > forsterite > α- alumina > magnetite > hematite > quartz > amorphous silica. Based on reported molecular-level information for adsorption of Gly on these minerals, polymerization activation was inferred to have arisen from deprotonation of the NH 3 + group of adsorbed Gly to the nucleophilic NH 2 group, and from withdrawal of electron density from the carboxyl carbon to the surface metal ions. The orientation of adsorbed Gly on minerals is also a factor influencing the Gly reactivity. The examination of Gly-mineral interactions under identical experimental conditions has enabled the direct comparison of various minerals' catalytic efficiencies and has made discussion of polymerization mechanisms and their relative influences possible Further systematic investigations using the approach reported herein (which are expected to be fruitful) combined with future microscopic surface analyses will elucidate the role of minerals in the process of abiotic peptide bond formation.

  3. Double plasma system with inductively coupled source plasma and quasi-quiescent target plasma

    International Nuclear Information System (INIS)

    Massi, M.; Maciel, H.S.

    1995-01-01

    Cold plasmas have successfully been used in the plasma-assisted material processing industry. An understanding of the physicochemical mechanisms involved in the plasma-surface interaction is needed for a proper description of deposition and etching processes at material surfaces. Since these mechanisms are dependent on the plasma properties, the development of diagnostic techniques is strongly desirable for determination of the plasma parameters as well as the characterization of the electromagnetic behaviour of the discharge. In this work a dual discharge chamber, was specially designed to study the deposition of thin films via plasma polymerization process. In the Pyrex chamber an inductively coupled plasma can be excited either in the diffuse low density E-mode or in the high density H-mode. This plasma diffuses into the cylindrical stainless steel chamber which is covered with permanent magnets to produce a multidipole magnetic field configuration at the surface. By that means a double plasma is established consisting of a RF source plasma coupled to a quasi-quiescent target plasma. The preliminary results presented here refer to measurements of the profiles of plasma parameters along the central axis of the double plasma apparatus. Additionally a spectrum analysis performed by means of a Rogowski coil probe immersed into the source plasma is also presented. The discharge is made in argon with pressure varying from 10 -2 to 1 torr, and the rf from 10 to 150 W

  4. pH-sensitive liposomes containing polymerized phosphatidylethanolamine and fatty acid.

    Science.gov (United States)

    Choi, M J; Han, H S; Kim, H

    1992-11-01

    With the ultimate aim of targeting cancer drugs to malignant tissues, liposomes containing polymeric phosphatidylethanolamine and a fatty acid were prepared. For this purpose diacetylenic phosphatidylethanolamine (DAPE), a phosphatidylethanolamine containing diacetylene, was synthesized. Liposomes containing DAPE, fatty acid, and either phosphatidylethanolamine (PE) or phosphatidylethanolamine-beta-oleoyl-gamma-palmitoyl (POPE) were then prepared. Polymerization of DAPE was effected by UV illumination. The polymeric liposomes so obtained were stable at physiological pH but became leaky below pH 6.5. Of various compositions studied, the greatest pH-sensitivity was found with liposomes composed of 35 mol% DAPE, 35 mol% POPE, and 30 mol% saturated fatty acid. The presence of blood plasma albumin decreased vesicle stability while apolipoprotein A-I (apo A-I) had the opposite effect and plasma as a whole had a slightly stabilizing effect.

  5. Characterizing concentrations of diethylene glycol and suspected metabolites in human serum, urine, and cerebrospinal fluid samples from the Panama DEG mass poisoning.

    Science.gov (United States)

    Schier, J G; Hunt, D R; Perala, A; McMartin, K E; Bartels, M J; Lewis, L S; McGeehin, M A; Flanders, W D

    2013-12-01

    Diethylene glycol (DEG) mass poisoning is a persistent public health problem. Unfortunately, there are no human biological data on DEG and its suspected metabolites in poisoning. If present and associated with poisoning, the evidence for use of traditional therapies such as fomepizole and/or hemodialysis would be much stronger. To characterize DEG and its metabolites in stored serum, urine, and cerebrospinal fluid (CSF) specimens obtained from human DEG poisoning victims enrolled in a 2006 case-control study. In the 2006 study, biological samples from persons enrolled in a case-control study (42 cases with new-onset, unexplained AKI and 140 age-, sex-, and admission date-matched controls without AKI) were collected and shipped to the Centers for Disease Control and Prevention (CDC) in Atlanta for various analyses and were then frozen in storage. For this study, when sufficient volume of the original specimen remained, the following analytes were quantitatively measured in serum, urine, and CSF: DEG, 2-hydroxyethoxyacetic acid (HEAA), diglycolic acid, ethylene glycol, glycolic acid, and oxalic acid. Analytes were measured using low resolution GC/MS, descriptive statistics calculated and case results compared with controls when appropriate. Specimens were de-identified so previously collected demographic, exposure, and health data were not available. The Wilcoxon Rank Sum test (with exact p-values) and bivariable exact logistic regression were used in SAS v9.2 for data analysis. The following samples were analyzed: serum, 20 case, and 20 controls; urine, 11 case and 22 controls; and CSF, 11 samples from 10 cases and no controls. Diglycolic acid was detected in all case serum samples (median, 40.7 mcg/mL; range, 22.6-75.2) and no controls, and in all case urine samples (median, 28.7 mcg/mL; range, 14-118.4) and only five (23%) controls (median, urine diglycolic acid (both OR > 999; exact p sample results were excluded and two from the same case were averaged, yielding

  6. Click polymerization for the synthesis of reduction-responsive polymeric prodrug

    Science.gov (United States)

    Zhang, Xiaojin; Wang, Hongquan; Dai, Yu

    2018-05-01

    Click polymerization is a powerful polymerization technique for the construction of new macromolecules with well-defined structures and multifaceted functionalities. Here, we synthesize reduction-responsive polymeric prodrug PEG- b-(PSS- g-MTX)- b-PEG containing disulfide bonds and pendant methotrexate (MTX) via two-step click polymerization followed by conjugating MTX to pendant hydroxyl. MTX content in polymeric prodrug is 13.5%. Polymeric prodrug is able to form polymeric micelles by self-assembly in aqueous solution. Polymeric micelles are spherical nanoparticles with tens of nanometers in size. Of note, polymeric micelles are reduction-responsive due to disulfide bonds in the backbone of PEG- b-(PSS- g-MTX)- b-PEG and could release pendant drugs in the presence of the reducing agents such as dl-dithiothreitol (DTT).

  7. SCATTERING FROM RAMIFIED POLYMERIC SYSTEMS

    Directory of Open Access Journals (Sweden)

    M.Benhamou

    2004-01-01

    Full Text Available Here, of great interest to us is a quantitative study of the scattering properties from ramified polymeric systems of arbitrary topology. We consider three types of systems, namely ramified polymers in solution, ramified polymer blends, or ternary mixtures made of two ramified polymers of different chemical nature immersed in a good solvent. To achieve the goal of the study, use is made of the Random Phase Approximation. First we determine the exact expression of the form factor of an ideal ramified polymer of any topology, from which we extract the exact expression of its gyration radius. Using the classical Zimm's formulae and the exact form factor, we determine all scattering properties of these three types of ramified polymeric systems. The main conclusion is that ramification of the chains induces drastic changes of the scattering properties.

  8. Adhesive F-actin Waves: A Novel Integrin-Mediated Adhesion Complex Coupled to Ventral Actin Polymerization

    OpenAIRE

    Case, Lindsay B.; Waterman, Clare M.

    2011-01-01

    At the leading lamellipodium of migrating cells, protrusion of an Arp2/3-nucleated actin network is coupled to formation of integrin-based adhesions, suggesting that Arp2/3-mediated actin polymerization and integrin-dependent adhesion may be mechanistically linked. Arp2/3 also mediates actin polymerization in structures distinct from the lamellipodium, in "ventral F-actin waves" that propagate as spots and wavefronts along the ventral plasma membrane. Here we show that integrins engage the ex...

  9. Polymeric nanoparticles for optical sensing.

    Science.gov (United States)

    Canfarotta, Francesco; Whitcombe, Michael J; Piletsky, Sergey A

    2013-12-01

    Nanotechnology is a powerful tool for use in diagnostic applications. For these purposes a variety of functional nanoparticles containing fluorescent labels, gold and quantum dots at their cores have been produced, with the aim of enhanced sensitivity and multiplexing capabilities. This work will review progress in the application of polymeric nanoparticles in optical diagnostics, both for in vitro and in vivo detection, together with a discussion of their biodistribution and biocompatibility. © 2013.

  10. Polymeric Coatings for Combating Biocorrosion

    Science.gov (United States)

    Guo, Jing; Yuan, Shaojun; Jiang, Wei; Lv, Li; Liang, Bin; Pehkonen, Simo O.

    2018-03-01

    Biocorrosion has been considered as big trouble in many industries and marine environments due to causing great economic loss. The main disadvantages of present approaches to prevent corrosion include being limited by environmental factors, being expensive, inapplicable to field, and sometimes inefficient. Studies show that polymer coatings with anti-corrosion and anti-microbial properties have been widely accepted as a novel and effective approach to preventbiocorrosion. The main purpose of this review is to summarize up the progressive status of polymer coatings used for combating microbially-induced corrosion. Polymers used to synthesize protective coatings are generally divided into three categories: i) traditional polymers incorporated with biocides, ii) antibacterial polymers containing quaternary ammonium compounds, and iii) conductive polymers. The strategies to synthesize polymer coatings resort mainly to grafting anti-bacterial polymers from the metal substrate surface using novel surface-functionalization approaches, such as free radical polymerization, chemically oxidative polymerization and surface-initiated atom transfer radical polymerization, as opposed to the traditional approaches of dip coating or spin coating.

  11. Non-equilibrium supramolecular polymerization.

    Science.gov (United States)

    Sorrenti, Alessandro; Leira-Iglesias, Jorge; Markvoort, Albert J; de Greef, Tom F A; Hermans, Thomas M

    2017-09-18

    Supramolecular polymerization has been traditionally focused on the thermodynamic equilibrium state, where one-dimensional assemblies reside at the global minimum of the Gibbs free energy. The pathway and rate to reach the equilibrium state are irrelevant, and the resulting assemblies remain unchanged over time. In the past decade, the focus has shifted to kinetically trapped (non-dissipative non-equilibrium) structures that heavily depend on the method of preparation (i.e., pathway complexity), and where the assembly rates are of key importance. Kinetic models have greatly improved our understanding of competing pathways, and shown how to steer supramolecular polymerization in the desired direction (i.e., pathway selection). The most recent innovation in the field relies on energy or mass input that is dissipated to keep the system away from the thermodynamic equilibrium (or from other non-dissipative states). This tutorial review aims to provide the reader with a set of tools to identify different types of self-assembled states that have been explored so far. In particular, we aim to clarify the often unclear use of the term "non-equilibrium self-assembly" by subdividing systems into dissipative, and non-dissipative non-equilibrium states. Examples are given for each of the states, with a focus on non-dissipative non-equilibrium states found in one-dimensional supramolecular polymerization.

  12. Nanoporous Polymeric Grating-Based Biosensors

    KAUST Repository

    Gao, Tieyu

    2012-05-02

    We demonstrate the utilization of an interferometrically created nanoporous polymeric gratings as a platform for biosensing applications. Aminopropyltriethoxysilane (APTES)-functionalized nanoporous polymeric gratings was fabricated by combining holographic interference patterning and APTES-functionalization of pre-polymer syrup. The successful detection of multiple biomolecules indicates that the biofunctionalized nanoporous polymeric gratings can act as biosensing platforms which are label-free, inexpensive, and applicable as high-throughput assays. Copyright © 2010 by ASME.

  13. Nanoporous Polymeric Grating-Based Biosensors

    KAUST Repository

    Gao, Tieyu; Hsiao, Vincent; Zheng, Yue Bing; Huang, Tony Jun

    2012-01-01

    We demonstrate the utilization of an interferometrically created nanoporous polymeric gratings as a platform for biosensing applications. Aminopropyltriethoxysilane (APTES)-functionalized nanoporous polymeric gratings was fabricated by combining holographic interference patterning and APTES-functionalization of pre-polymer syrup. The successful detection of multiple biomolecules indicates that the biofunctionalized nanoporous polymeric gratings can act as biosensing platforms which are label-free, inexpensive, and applicable as high-throughput assays. Copyright © 2010 by ASME.

  14. Volumetric polymerization shrinkage of contemporary composite resins

    OpenAIRE

    Nagem Filho, Halim; Nagem, Haline Drumond; Francisconi, Paulo Afonso Silveira; Franco, Eduardo Batista; Mondelli, Rafael Francisco Lia; Coutinho, Kennedy Queiroz

    2007-01-01

    The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill ...

  15. Polymeric membrane materials for artificial organs.

    Science.gov (United States)

    Kawakami, Hiroyoshi

    2008-01-01

    Many polymeric materials have already been used in the field of artificial organs. However, the materials used in artificial organs are not necessarily created with the best material selectivity and materials design; therefore, the development of synthesized polymeric membrane materials for artificial organs based on well-defined designs is required. The approaches to the development of biocompatible polymeric materials fall into three categories: (1) control of physicochemical characteristics on material surfaces, (2) modification of material surfaces using biomolecules, and (3) construction of biomimetic membrane surfaces. This review will describe current issues regarding polymeric membrane materials for use in artificial organs.

  16. High Vacuum Techniques for Anionic Polymerization

    KAUST Repository

    Ratkanthwar, Kedar

    2015-09-01

    Anionic polymerization high vacuum techniques (HVTs) are the most suitable for the preparation of polymer samples with well-defined complex macromolecular architectures. Though HVTs require glassblowing skill for designing and making polymerization reactor, it is the best way to avoid any termination of living polymers during the number of steps for the synthesis of polymers with complex structure. In this chapter, we describe the different polymerization reactors and HVTs for the purification of monomers, solvents, and other reagents for anionic polymerization as well as few model reactions for the synthesis of polymers with simple to complex structure.

  17. Functionalized Ormosil Scaffolds Processed by Direct Laser Polymerization for Application in Tissue Engineering

    DEFF Research Database (Denmark)

    Matei, A.; Schou, Jørgen; Canulescu, Stela

    The N,N’-(methacryloyloxyethyl triehtoxy silyl propyl carbamoyl-oxyhexyl)-urea hybrid methacrylate for applications in tissue engineering was synthesized and afterwards polymerized by direct laser polymerization using femtosecond laser pulses with the aim of using it for further applications...... in tissue engineering. The as-obtained scaffolds were modified either by low pressure argon plasma treatment or by using two different proteins (lysozyme, fibrinogen). For improved adhesion, the proteins were deposited by matrix assisted pulsed laser evaporation. The functionalized structures were tested...

  18. Twin screw extruders as polymerization reactors for a free radical homo polymerization

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Janssen, L.P.B.M.

    The bulk polymerization of n-butylmethacrylate was investigated in a counter-rotating twin screw extruder. It appeared that the gel effect, occurring with bulk polymerizations, affected the polymerization progress very strongly. Due to this effect the conversion of the reaction is independent of the

  19. Advances and challenges in the field of plasma polymer nanoparticles

    Directory of Open Access Journals (Sweden)

    Andrei Choukourov

    2017-09-01

    Full Text Available This contribution reviews plasma polymer nanoparticles produced by gas aggregation cluster sources either via plasma polymerization of volatile monomers or via radio frequency (RF magnetron sputtering of conventional polymers. The formation of hydrocarbon, fluorocarbon, silicon- and nitrogen-containing plasma polymer nanoparticles as well as core@shell nanoparticles based on plasma polymers is discussed with a focus on the development of novel nanostructured surfaces.

  20. Physico-chemical properties of plasma-polymerized tetravinylsilane

    Czech Academy of Sciences Publication Activity Database

    Čech, V.; Studynka, J.; Conte, N.; Peřina, Vratislav

    2007-01-01

    Roč. 201, 9-11 (2007), s. 5512-5517 ISSN 0257-8972 Institutional research plan: CEZ:AV0Z10480505 Keywords : nano -indentation Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.678, year: 2007

  1. A plasma polymerization technique to overcome cerebrospinal fluid shunt infections

    Czech Academy of Sciences Publication Activity Database

    Çökeliler, D.; Caner, H.; Zemek, Josef; Choukourov, A.; Biederman, H.; Mutlu, M.

    2007-01-01

    Roč. 2, č. 1 (2007), s. 39-47 ISSN 1748-6041 Grant - others:TUBITAK(TR) MISAG-COST 527 Institutional research plan: CEZ:AV0Z10100521 Keywords : shunt infections * cerebrospinal * PP HEMA * biomaterials Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.787, year: 2007

  2. Characterization of poly(methylphenylsilane) prepared by plasma polymerization

    Czech Academy of Sciences Publication Activity Database

    Čech, V.; Horváth, P.; Jančář, J.; Schauer, F.; Nešpůrek, Stanislav

    1999-01-01

    Roč. 148, - (1999), s. 321-332 ISSN 1022-1360. [International Conference on Polymer Characterization Polychar-7. Denton, 05.01.1999-11.01.1999] R&D Projects: GA ČR GV106/98/K013; GA ČR GA101/98/0855 Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.539, year: 1999

  3. Tailoring Silica Surface Properties by Plasma Polymerization for Elastomer Applications

    NARCIS (Netherlands)

    Tiwari, M.; Dierkes, Wilma K.; Datta, Rabin; Talma, Auke; Noordermeer, Jacobus W.M.; van Ooij, W.J.

    2009-01-01

    The surface properties of reinforcing fillers are a crucial factor for dispersion and filler–polymer interaction in rubber compounds, as they strongly influence the final vulcanized properties of the rubber article. Silica is gaining more and more importance as reinforcing filler for rubbers, as it

  4. Tailoring Silica Surface Properties by Plasma Polymerization for Elastomer Applications

    NARCIS (Netherlands)

    Tiwari, M.; Dierkes, W.K.; Datta, R.N.; Talma, A.G.; Noordermeer, J.W.M.; van Ooij, W.J.

    2011-01-01

    The surface properties of reinforcing fillers are a crucial factor for dispersion and filler–polymer interaction in rubber compounds, as they strongly influence the final vulcanized properties of the rubber article. Silica is gaining more and more importance as reinforcing filler for rubbers, as it

  5. Schlenk Techniques for Anionic Polymerization

    KAUST Repository

    Ratkanthwar, Kedar

    2015-09-01

    Anionic polymerization-high vacuum techniques (HVTs) are doubtlessly the most prominent and reliable experimental tools to prepare polymer samples with well-defined and, in many cases, complex macromolecular architectures. Due to the high demands for time and skilled technical personnel, HVTs are currently used in only a few research laboratories worldwide. Instead, most researchers in this filed are attracted to more facile Schlenk techniques. The basic principle of this technique followed in all laboratories is substantially the same, i.e. the use of alternate vacuum and inert gas atmosphere in glass apparatus for the purification/charging of monomer, solvents, additives, and for the manipulation of air-sensitive compounds such as alkyl metal initiators, organometallic or organic catalysts. However, it is executed quite differently in each research group in terms of the structure of Schlenk apparatus (manifolds, connections, purification/storage flasks, reactors, etc.), the use of small supplementary devices (soft tubing, cannulas, stopcocks, etc.) and experimental procedures. The operational methods are partly purpose-oriented while also featured by a high flexibility, which makes it impossible to describe in detail each specific one. In this chapter we will briefly exemplify the application of Schlenk techniques for anionic polymerization by describing the performance of a few experiments from our own work.

  6. Plasma chemistry in wire chambers

    International Nuclear Information System (INIS)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an 55 Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed

  7. Polymeric implant of methylprednisolone for spinal injury ...

    African Journals Online (AJOL)

    Polymeric implant of methylprednisolone for spinal injury: preparation and characterization. Bo Yin, Jian-Jun Ji, Ming Yang. Abstract. Purpose: To improve the effectiveness and reduce the systemic side effects of methylprednisolone in traumatic spinal injuries, its polymeric implants were prepared using chitosan and sodium ...

  8. Nanoparticles from a controlled polymerization process

    International Nuclear Information System (INIS)

    Tirumala, V.R.; Caneba, G.T.; Dar, Y.; Wang, H.-H.; Mancini, D.C.

    2003-01-01

    Free-radical retrograde precipitation polymerization process in the past has shown excellent control characteristics over reaction rate, molecular weight, and in the entrapment of live radicals for the generation of block copolymers. The same principle has now been extended to study the reaction confinement to a nanoscale region. Nanosized polymer particles have been reported to form from block copolymers, conventional precipitation polymerization methods, or through emulsion polymerization approaches. In this work, we present a new method of generating nanosized polymer particles by polymerizing the monomer in an environment that precipitates the polymer above the lower critical solution temperature. The nanoparticles have been characterized by both tapping-mode atomic force microscopy observations and in situ synchrotron time-resolved small-angle X-ray scattering analysis. The results from both the techniques showed the formation of nanoparticles in the size range of 15-30 nm, directly from the polymerization process.

  9. Fluid Effects in Polymers and Polymeric Composites

    CERN Document Server

    Weitsman, Y Jack

    2012-01-01

    Fluid Effects in Polymers and Polymeric Composites, written by the late Dr. Y. Jack Weitsman, addresses the wide range of parameters that affect the interaction of fluids with polymers and polymeric composites. The book aims at broadening the scope of available data, mostly limited up to this time to weight-gain recordings of fluid ingress into polymers and composites, to the practical circumstances of fluctuating exposure. Various forms of experimental data are given, in conjunction with theoretical models derived from basic scientific principles, and correlated with severity of exposure conditions and interpreted by means of rationally based theoretical models. The practical implications of the effects of fluids are discussed. The issue of fluid effects on polymers and polymeric composites is of concern to engineers and scientists active in aerospace and naval structures, as an increasing portion of these structures are made of polymeric composites and employ polymeric adhesives as a joining device. While...

  10. Cyanex based uranyl sensitive polymeric membrane electrodes.

    Science.gov (United States)

    Badr, Ibrahim H A; Zidan, W I; Akl, Z F

    2014-01-01

    Novel uranyl selective polymeric membrane electrodes were prepared using three different low-cost and commercially available Cyanex extractants namely, bis(2,4,4-trimethylpentyl) phosphinic acid [L1], bis(2,4,4-trimethylpentyl) monothiophosphinic acid [L2] and bis(2,4,4-trimethylpentyl) dithiophosphinic acid [L3]. Optimization and performance characteristics of the developed Cyanex based polymer membrane electrodes were determined. The influence of membrane composition (e.g., amount and type of ionic sites, as well as type of plasticizer) on potentiometric responses of the prepared membrane electrodes was studied. Optimized Cyanex-based membrane electrodes exhibited Nernstian responses for UO₂(2+) ion over wide concentration ranges with fast response times. The optimized membrane electrodes based on L1, L2 and L3 exhibited Nernstian responses towards uranyl ion with slopes of 29.4, 28.0 and 29.3 mV decade(-1), respectively. The optimized membrane electrodes based on L1-L3 showed detection limits of 8.3 × 10(-5), 3.0 × 10(-5) and 3.3 × 10(-6) mol L(-1), respectively. The selectivity studies showed that the optimized membrane electrodes exhibited high selectivity towards UO₂(2+) ion over large number of other cations. Membrane electrodes based on L3 exhibited superior potentiometric response characteristics compared to those based on L1 and L2 (e.g., widest linear range and lowest detection limit). The analytical utility of uranyl membrane electrodes formulated with Cyanex extractant L3 was demonstrated by the analysis of uranyl ion in different real samples for nuclear safeguards verification purposes. The results obtained using direct potentiometry and flow-injection methods were compared with those measured using the standard UV-visible and inductively coupled plasma spectroscopic methods. © 2013 Published by Elsevier B.V.

  11. Modeling liquid crystal polymeric devices

    Science.gov (United States)

    Gimenez Pinto, Vianney Karina

    The main focus of this work is the theoretical and numerical study of materials that combine liquid crystal and polymer. Liquid crystal elastomers are polymeric materials that exhibit both the ordered properties of the liquid crystals and the elastic properties of rubbers. Changing the order of the liquid crystal molecules within the polymer network can induce shape change. These materials are very valuable for applications such as actuators, sensors, artificial muscles, haptic displays, etc. In this work we apply finite element elastodynamics simulations to study the temperature induced shape deformation in nematic elastomers with complex director microstructure. In another topic, we propose a novel numerical method to model the director dynamics and microstructural evolution of three dimensional nematic and cholesteric liquid crystals. Numerical studies presented in this work are in agreement with experimental observations and provide insight into the design of application devices.

  12. Polymerization of lanthanide acrylonitrile complexes.

    Science.gov (United States)

    el-Mossalamy, El-Sayed H; Khalil, Ahmed A

    2002-01-01

    The molecular complexes of some lanthanides scandium (Sc3+), yttrium (Y3+), lanthanum (La3+), gadolinium (Gd3+), cerium (Ce3+) and ytterbium (Yb3) have been studies in dimethyl formamide (DMF) spectrophtometrically equilibrium constants (K), molar extintion coefficient (epsilon), energy of transition (E) and free energy (delta G*) were calculated. The polymerization of acrylonitrile has been studied and investigated in the presence of Sc3+, Y3+, La3+, Gd3+, Ce3+, and Yb3+ ions. The IR spectra of the formed AN-M (III) Br3 polymer complexes show the absence of the C identical to N band and the presence of two new bands corresponding to NH2 and OH groups. Magnetic moment values and the thermal stabilities of homopolymer and the polymer complexes were studied by means of thermogravimetric analysis and the activation energies for degradation were calculated.

  13. Polymeric materials from renewable resources

    Energy Technology Data Exchange (ETDEWEB)

    Frollini, Elisabete; Rodrigues, Bruno V. M.; Silva, Cristina G. da; Castro, Daniele O.; Ramires, Elaine C.; Oliveira, Fernando de; Santos, Rachel P. O. [Macromolecular Materials and Lignocellulosic Fibers Group, Center for Research on Science and Technology of BioResources, Institute of Chemistry of São Carlos, University of São Paulo, CP 780, 13560-970 São Carlos, São Paulo (Brazil)

    2016-05-18

    The goals of our studies have been the use of renewable raw materials in the preparation of polymeric materials with diversified properties. In this context, lignosulfonate, which is produced in large scale around the world, but not widely used in the production of polymeric materials, was used to replace phenol and polyols in the preparation of phenolic- (Ligno-PH) and polyurethane-type (Ligno-PU) polymers, respectively. These polymers were used to prepare composites reinforced with sisal lignocellulosic fibers. The use of lignosulfonate in the formulation of both types of polymers was beneficial, because in general composites with improved properties, specially impact strength, were obtained. Composites were also prepared from the so called “biopolyethylene” (HDPE), curaua lignocellulosic fiber, and castor oil (CO). All composites HDBPE/CO/Fiber exhibited higher impact strength, when compared to those of the corresponding HDBPE/Fiber. These results, combined with others (eg SEM images of the fractured surfaces) indicated that, in addition to acting as a plasticizer, this oil may have acted as a compatibilizer of the hydrophilic fiber with the hydrophobic polymer. The set of results indicated that (i) mats with nano (diameter ≤ 100nm) and/or ultrafine (submicron scale) fibers were produced, (ii) hybrid fibers were produced (bio-based mats composites), (iii) cellulosic pulp (CP) and/or lignin (Lig) can be combined with PET matrices to control properties such as stiffness and hydrophilicity of the respective mats. Materials with diversified properties were prepared from high content of renewable raw materials, thus fulfilling the proposed targets.

  14. Polymeric materials from renewable resources

    Science.gov (United States)

    Frollini, Elisabete; Rodrigues, Bruno V. M.; da Silva, Cristina G.; Castro, Daniele O.; Ramires, Elaine C.; de Oliveira, Fernando; Santos, Rachel P. O.

    2016-05-01

    The goals of our studies have been the use of renewable raw materials in the preparation of polymeric materials with diversified properties. In this context, lignosulfonate, which is produced in large scale around the world, but not widely used in the production of polymeric materials, was used to replace phenol and polyols in the preparation of phenolic- (Ligno-PH) and polyurethane-type (Ligno-PU) polymers, respectively. These polymers were used to prepare composites reinforced with sisal lignocellulosic fibers. The use of lignosulfonate in the formulation of both types of polymers was beneficial, because in general composites with improved properties, specially impact strength, were obtained. Composites were also prepared from the so called "biopolyethylene" (HDPE), curaua lignocellulosic fiber, and castor oil (CO). All composites HDBPE/CO/Fiber exhibited higher impact strength, when compared to those of the corresponding HDBPE/Fiber. These results, combined with others (eg SEM images of the fractured surfaces) indicated that, in addition to acting as a plasticizer, this oil may have acted as a compatibilizer of the hydrophilic fiber with the hydrophobic polymer. The set of results indicated that (i) mats with nano (diameter ≤ 100nm) and/or ultrafine (submicron scale) fibers were produced, (ii) hybrid fibers were produced (bio-based mats composites), (iii) cellulosic pulp (CP) and/or lignin (Lig) can be combined with PET matrices to control properties such as stiffness and hydrophilicity of the respective mats. Materials with diversified properties were prepared from high content of renewable raw materials, thus fulfilling the proposed targets.

  15. Method for forming polymerized microfluidic devices

    Science.gov (United States)

    Sommer, Gregory J.; Hatch, Anson V.; Wang, Ying-Chih; Singh, Anup K.; Renzi, Ronald F.; Claudnic, Mark R.

    2013-03-12

    Methods for making a microfluidic device according to embodiments of the present invention include defining.about.cavity. Polymer precursor solution is positioned in the cavity, and exposed to light to begin the polymerization process and define a microchannel. In some embodiments, after the polymerization process is partially complete, a solvent rinse is performed, or fresh polymer precursor introduced into the microchannel. This may promote removal of unpolymerized material from the microchannel and enable smaller feature sizes. The polymer precursor solution may contain an iniferter. Polymerized features therefore may be capped with the iniferter, which is photoactive. The iniferter may aid later binding of a polyacrylamide gel to the microchannel surface.

  16. AZIDE-ALKYNE CLICK POLYMERIZATION: AN UPDATE

    Institute of Scientific and Technical Information of China (English)

    Hong-kun Li; Jing-zhi Sun; An-jun Qin; Ben Zhong Tang

    2012-01-01

    The great achievements of click chemistry have encouraged polymer scientists to use this reaction in their field.This review assembles an update of the advances of using azide-alkyne click polymerization to prepare functional polytriazoles (PTAs) with linear and hyperbranched structures.The Cu(Ⅰ)-mediated click polymerization furnishes 1,4-regioregular PTAs,whereas,the metal-free click polymerization of propiolates and azides produces PTAs with 1,4-regioisomer contents up to 90%.The PTAs display advanced functions,such as aggregation-induced emission,thermal stability,biocompatibility and optical nonlinearity.

  17. Plasma polymer-functionalized silica particles for heavy metals removal.

    Science.gov (United States)

    Akhavan, Behnam; Jarvis, Karyn; Majewski, Peter

    2015-02-25

    Highly negatively charged particles were fabricated via an innovative plasma-assisted approach for the removal of heavy metal ions. Thiophene plasma polymerization was used to deposit sulfur-rich films onto silica particles followed by the introduction of oxidized sulfur functionalities, such as sulfonate and sulfonic acid, via water-plasma treatments. Surface chemistry analyses were conducted by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy. Electrokinetic measurements quantified the zeta potentials and isoelectric points (IEPs) of modified particles and indicated significant decreases of zeta potentials and IEPs upon plasma modification of particles. Plasma polymerized thiophene-coated particles treated with water plasma for 10 min exhibited an IEP of less than 3.5. The effectiveness of developed surfaces in the adsorption of heavy metal ions was demonstrated through copper (Cu) and zinc (Zn) removal experiments. The removal of metal ions was examined through changing initial pH of solution, removal time, and mass of particles. Increasing the water plasma treatment time to 20 min significantly increased the metal removal efficiency (MRE) of modified particles, whereas further increasing the plasma treatment time reduced the MRE due to the influence of an ablation mechanism. The developed particulate surfaces were capable of removing more than 96.7% of both Cu and Zn ions in 1 h. The combination of plasma polymerization and oxidative plasma treatment is an effective method for the fabrication of new adsorbents for the removal of heavy metals.

  18. Synthesis and polymerization of vinyl triazolium ionic liquids

    Science.gov (United States)

    Luebke, David; Nulwala, Hunaid; Matyjaszewski, Krzysztof; Adzima, Brian

    2018-05-15

    Herein, we describe polymerized ionic liquids, demonstrate the synthesis of polymerized ionic liquids, and demonstrate the polymerization of triazolium monomers. One embodiment shows the polymeriazation of the triazolium monomers with bis(trifluoromethanesulfonyl)imide anions. In another embodiment we show the feasibility of copolymerizing with commodity monomers such as styrene using free radical polymerization techniques.

  19. A simple diethylene glycol-assisted synthesis and high rate performance of Li3V2(PO4)3/C composites as cathode material for Li-ion batteries

    International Nuclear Information System (INIS)

    Liu, Qianjin; Yang, Fei; Wang, Shuping; Feng, Lijun; Zhang, Wenjing; Wei, Huiying

    2013-01-01

    Spherical Li 3 V 2 (PO 4 ) 3 /C(LVP/C) composites were synthesized by sol–gel method using diethylene glycol as the spheroidizing medium and glucose as the carbon source. The crystal structure, morphology, the lithium diffusion behavior and high rates capacities were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and electrochemical methods. Results indicated that the sphere-like LVP/C sample prepared with 10 wt% glucose has a uniform carbon layer about 10 nm on the surfaces, and presented a high discharge capacity of 131.8, 126.5, 102.4, 82.8 mAh g −1 at 0.1, 2, 10, 20 C between 3.0 and 4.3 V with no obvious capacity fading during 200 cycles at the rate of 2 C. While in the voltage region of 3.0–4.8 V, it owned the largest reversible capacity of 169.4, 139.8, 121.7 mAh g −1 at 0.5, 1, 5 C, respectively. Its capacity retained 79.9% after 200 cycles at 2 C, and the apparent Li-ion diffusion coefficient was calculated to be 3.37 × 10 −9 cm 2 s −1

  20. An X-band Co2+ EPR study of Zn1-xCoxO (x=0.005-0.1) nanoparticles prepared by chemical hydrolysis methods using diethylene glycol and denaturated alcohol at 5 K

    Science.gov (United States)

    Misra, Sushil K.; Andronenko, S. I.; Srinivasa Rao, S.; Chess, Jordan; Punnoose, A.

    2015-11-01

    EPR investigations on two types of dilute magnetic semiconductor (DMS) ZnO nanoparticles doped with 0.5-10% Co2+ ions, prepared by two chemical hydrolysis methods, using: (i) diethylene glycol ((CH2CH2OH)2O) (NC-rod-like samples), and (ii) denatured ethanol (CH3CH2OH) solutions (QC-spherical samples), were carried out at X-band (9.5 GHz) at 5 K. The analysis of EPR data for NC samples revealed the presence of several types of EPR lines: (i) two types, intense and weak, of high-spin Co2+ ions in the samples with Co concentration >0.5%; (ii) surface oxygen vacancies, and (iii) a ferromagnetic resonance (FMR) line. QC samples exhibit an intense FMR line and an EPR line due to high-spin Co2+ ions. FMR line is more intense, than the corresponding line exhibited by NC samples. These EPR spectra varied for sample with different doping concentrations. The magnetic states of these samples as revealed by EPR spectra, as well as the origin of ferromagnetism DMS samples are discussed.

  1. Better flocculants by radiation induced polymerization

    International Nuclear Information System (INIS)

    Laizier, J.; Gaussens, G.

    1978-01-01

    The use of radiation induced polymerization should theoritically allow to prepare better flocculants. The testings of several products prepared by such a process shows that better properties are indeed obtained: better efficiencies, lower amounts needed, better overall properties [fr

  2. Compression Behavior of High Performance Polymeric Fibers

    National Research Council Canada - National Science Library

    Kumar, Satish

    2003-01-01

    Hydrogen bonding has proven to be effective in improving the compressive strength of rigid-rod polymeric fibers without resulting in a decrease in tensile strength while covalent crosslinking results in brittle fibers...

  3. Silicon dioxide obtained by Polymeric Precursor Method

    International Nuclear Information System (INIS)

    Oliveira, C.T.; Granado, S.R.; Lopes, S.A.; Cavalheiro, A.A.

    2011-01-01

    The Polymeric Precursor Method is able for obtaining several oxide material types with high surface area even obtained in particle form. Several MO 2 oxide types such as titanium, silicon and zirconium ones can be obtained by this methodology. In this work, the synthesis of silicon oxide was monitored by thermal analysis, XRD and surface area analysis in order to demonstrate the influence of the several synthesis and calcining parameters. Surface area values as higher as 370m2/g and increasing in the micropore volume nm were obtained when the material was synthesized by using ethylene glycol as polymerizing agent. XRD analysis showed that the material is amorphous when calcinated at 600°C in despite of the time of calcining, but the material morphology is strongly influenced by the polymeric resin composition. Using Glycerol as polymerizing agent, the pore size increase and the surface area goes down with the increasing in decomposition time, when compared to ethylene glycol. (author)

  4. Thermal polymerization of Moringa oleifera oil

    International Nuclear Information System (INIS)

    Melo, Tania M.S.; Novack, Katia M.; Leandro, Cristiano

    2011-01-01

    It is increasingly clear both for society and the scientific community, that is necessary to find alternatives to reduce the use of polymeric materials because of their damage to the environment. One way to minimize the environmental problems related to the use of polymers is try to make them quickly degradable. In this study it was obtained a material with polymeric appearance derived from heating of the vegetable oil extracted from seeds of Moringa oleifera. The resulting product is an interesting alternative to obtain polymeric materials that may have biodegradable characteristics, coming from a renewable source and low cost. Moringa oil can be used since it has a high content of unsaturated fatty acids, and its main constituent oleic acid. All samples were characterized by FTIR, NMR and GPC. It was obtained a polymeric material, malleable, high viscosity, with some elasticity, low crystallinity and no unpleasant odor. (author)

  5. Deformation and flow of polymeric materials

    CERN Document Server

    Münstedt, Helmut

    2014-01-01

    This book describes the properties of single polymer molecules and polymeric materials and the methods how to characterize them. Molar masses, molar mass distributions and branching structure are discussed in detail. These properties are decisive for a deeper understanding of structure/properties relationships of polymeric materials. This book therefore describes and discusses them in detail. The mechanical behavior as a function of time and temperature is a key subject of the book. The authors present it on the basis of many original results they have obtained in their long research careers. They present the temperature dependence of mechanical properties of various polymeric materials in a wide temperature range: from cryogenic temperatures to the melt. Besides an extensive data collection on the transitions of various different polymeric materials, they also carefully present the physical explanations of the observed phenomena. Glass transition and melting temperatures are discussed, particularly, with the...

  6. Polymerization of sodium methacrylate induced by irradiation

    International Nuclear Information System (INIS)

    Galvan S, A.

    1998-01-01

    This work has two objectives, first: it is pretended to localize the lines of carbon links in its IR spectra, and second: following the polymerization of sodium methacrylate according to that it is irradiated with gamma rays. (Author)

  7. Bioadhesive polymeric platforms for transmucosal drug delivery ...

    African Journals Online (AJOL)

    Bioadhesive polymeric platforms for transmucosal drug delivery systems – a review. ... administration of certain classes of drugs, especially peptides and proteins. ... characteristics of desired bioadhesive polymers, this article then proceeds to ...

  8. Transformation kinetics of mixed polymeric substrates under ...

    African Journals Online (AJOL)

    bglucosidase and a-mannosidase were abundantly secreted in the growth medium. This research is the first report on mixed polymeric substrate biodegradation under sewer condition by A. niger, and could be considered as an open window on ...

  9. Post polymerization cure shape memory polymers

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Thomas S.; Hearon, II, Michael Keith; Bearinger, Jane P.

    2017-01-10

    This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape memory behavior (SMPs) and which can first be polymerized to a linear or branched polymeric structure, having thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions and then crossed linked to a shape memory thermoset polymer retaining the processed shape.

  10. Nucleotide Selectivity in Abiotic RNA Polymerization Reactions

    Science.gov (United States)

    Coari, Kristin M.; Martin, Rebecca C.; Jain, Kopal; McGown, Linda B.

    2017-09-01

    In order to establish an RNA world on early Earth, the nucleotides must form polymers through chemical rather than biochemical reactions. The polymerization products must be long enough to perform catalytic functions, including self-replication, and to preserve genetic information. These functions depend not only on the length of the polymers, but also on their sequences. To date, studies of abiotic RNA polymerization generally have focused on routes to polymerization of a single nucleotide and lengths of the homopolymer products. Less work has been done the selectivity of the reaction toward incorporation of some nucleotides over others in nucleotide mixtures. Such information is an essential step toward understanding the chemical evolution of RNA. To address this question, in the present work RNA polymerization reactions were performed in the presence of montmorillonite clay catalyst. The nucleotides included the monophosphates of adenosine, cytosine, guanosine, uridine and inosine. Experiments included reactions of mixtures of an imidazole-activated nucleotide (ImpX) with one or more unactivated nucleotides (XMP), of two or more ImpX, and of XMP that were activated in situ in the polymerization reaction itself. The reaction products were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the lengths and nucleotide compositions of the polymerization products. The results show that the extent of polymerization, the degree of heteropolymerization vs. homopolymerization, and the composition of the polymeric products all vary among the different nucleotides and depend upon which nucleotides and how many different nucleotides are present in the mixture.

  11. Polymeric Nanogels Obtained by Radiation Technique

    Energy Technology Data Exchange (ETDEWEB)

    Ulanski, P.; Kadłubowski, A. K.; Olejnik,; Rokita, B.; Wach, R.; Rosiak, J. M. [Institute of Applied Radiation Chemistry, Technical University of Lodz, Lodz (Poland)

    2009-07-01

    Soft nanomaterials - polymeric nanogels and microgels - have made a fast and brilliant career, from an unwanted by-product of polymerization processes to an important and fashionable topic of interdisciplinary research in the fields of polymer chemistry and physics, materials science, pharmacy and medicine. Together with their larger analogues - macroscopic gels, most known in the form of water-swellable hydrogels - they have a broad field of actual and potential applications ranging from filler materials in coating industry to modern biomaterials.

  12. Nucleotide Selectivity in Abiotic RNA Polymerization Reactions.

    Science.gov (United States)

    Coari, Kristin M; Martin, Rebecca C; Jain, Kopal; McGown, Linda B

    2017-09-01

    In order to establish an RNA world on early Earth, the nucleotides must form polymers through chemical rather than biochemical reactions. The polymerization products must be long enough to perform catalytic functions, including self-replication, and to preserve genetic information. These functions depend not only on the length of the polymers, but also on their sequences. To date, studies of abiotic RNA polymerization generally have focused on routes to polymerization of a single nucleotide and lengths of the homopolymer products. Less work has been done the selectivity of the reaction toward incorporation of some nucleotides over others in nucleotide mixtures. Such information is an essential step toward understanding the chemical evolution of RNA. To address this question, in the present work RNA polymerization reactions were performed in the presence of montmorillonite clay catalyst. The nucleotides included the monophosphates of adenosine, cytosine, guanosine, uridine and inosine. Experiments included reactions of mixtures of an imidazole-activated nucleotide (ImpX) with one or more unactivated nucleotides (XMP), of two or more ImpX, and of XMP that were activated in situ in the polymerization reaction itself. The reaction products were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the lengths and nucleotide compositions of the polymerization products. The results show that the extent of polymerization, the degree of heteropolymerization vs. homopolymerization, and the composition of the polymeric products all vary among the different nucleotides and depend upon which nucleotides and how many different nucleotides are present in the mixture.

  13. Volumetric polymerization shrinkage of contemporary composite resins

    Directory of Open Access Journals (Sweden)

    Halim Nagem Filho

    2007-10-01

    Full Text Available The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill Magic, Alert, and Solitaire to determine whether there are differences among these materials. The tests were conducted with precision of 0.1 mg. The volumetric shrinkage was measured by hydrostatic weighing before and after polymerization and calculated by known mathematical equations. One-way ANOVA (a or = 0.05 was used to determine statistically significant differences in volumetric shrinkage among the tested composite resins. Suprafill (1.87±0.01 and Definite (1.89±0.01 shrank significantly less than the other composite resins. SureFil (2.01±0.06, Filtek Z250 (1.99±0.03, and Fill Magic (2.02±0.02 presented intermediate levels of polymerization shrinkage. Alert and Solitaire presented the highest degree of polymerization shrinkage. Knowing the polymerization shrinkage rates of the commercially available composite resins, the dentist would be able to choose between using composite resins with lower polymerization shrinkage rates or adopting technical or operational procedures to minimize the adverse effects deriving from resin contraction during light-activation.

  14. Post polymerization cure shape memory polymers

    Science.gov (United States)

    Wilson, Thomas S; Hearon, Michael Keith; Bearinger, Jane P

    2014-11-11

    This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape memory behavior (SMPs) and which can first be polymerized to a linear or branched polymeric structure, having thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions and then crossed linked to a shape memory thermoset polymer retaining the processed shape.

  15. Polymeric Nanogels Obtained by Radiation Technique

    International Nuclear Information System (INIS)

    Ulanski, P.; Kadłubowski, A.K.; Olejnik; Rokita, B.; Wach, R.; Rosiak, J.M.

    2009-01-01

    Soft nanomaterials - polymeric nanogels and microgels - have made a fast and brilliant career, from an unwanted by-product of polymerization processes to an important and fashionable topic of interdisciplinary research in the fields of polymer chemistry and physics, materials science, pharmacy and medicine. Together with their larger analogues - macroscopic gels, most known in the form of water-swellable hydrogels - they have a broad field of actual and potential applications ranging from filler materials in coating industry to modern biomaterials

  16. Stimuli-Responsive Polymeric Nanoparticles.

    Science.gov (United States)

    Liu, Xiaolin; Yang, Ying; Urban, Marek W

    2017-07-01

    There is increasing evidence that stimuli-responsive nanomaterials have become significantly critical components of modern materials design and technological developments. Recent advances in synthesis and fabrication of stimuli-responsive polymeric nanoparticles with built-in stimuli-responsive components (Part A) and surface modifications of functional nanoparticles that facilitate responsiveness (Part B) are outlined here. The synthesis and construction of stimuli-responsive spherical, core-shell, concentric, hollow, Janus, gibbous/inverse gibbous, and cocklebur morphologies are discussed in Part A, with the focus on shape, color, or size changes resulting from external stimuli. Although inorganic/metallic nanoparticles exhibit many useful properties, including thermal or electrical conductivity, catalytic activity, or magnetic properties, their assemblies and formation of higher order constructs are often enhanced by surface modifications. Section B focuses on selected surface reactions that lead to responsiveness achieved by decorating nanoparticles with stimuli-responsive polymers. Although grafting-to and grafting-from dominate these synthetic efforts, there are opportunities for developing novel synthetic approaches facilitating controllable recognition, signaling, or sequential responses. Many nanotechnologies utilize a combination of organic and inorganic phases to produce ceramic or metallic nanoparticles. One can envision the development of new properties by combining inorganic (metals, metal oxides) and organic (polymer) phases into one nanoparticle designated as "ceramers" (inorganics) and "metamers" (metallic). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. On the enhancement of pervaporation properties of plasma-deposited hybrid silica membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ngamou, P.H.T.; Creatore, M. [Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Overbeek, J.P.; Kreiter, R.; Van Veen, H.M.; Vente, J.F. [ECN, Energy research Centre of the Netherlands, Petten (Netherlands); Cuperus, P.F. [SolSep BV, Apeldoorn (Netherlands)

    2013-06-24

    The separation performance of a polymeric-supported hybrid silica membrane in the dehydration process of a butanol-water mixture at 95C has been enhanced by applying a bias to the substrate during the plasma deposition.

  18. Nonperturbative Renormalization Group Approach to Polymerized Membranes

    Science.gov (United States)

    Essafi, Karim; Kownacki, Jean-Philippe; Mouhanna, Dominique

    2014-03-01

    Membranes or membrane-like materials play an important role in many fields ranging from biology to physics. These systems form a very rich domain in statistical physics. The interplay between geometry and thermal fluctuations lead to exciting phases such flat, tubular and disordered flat phases. Roughly speaking, membranes can be divided into two group: fluid membranes in which the molecules are free to diffuse and thus no shear modulus. On the other hand, in polymerized membranes the connectivity is fixed which leads to elastic forces. This difference between fluid and polymerized membranes leads to a difference in their critical behaviour. For instance, fluid membranes are always crumpled, whereas polymerized membranes exhibit a phase transition between a crumpled phase and a flat phase. In this talk, I will focus only on polymerized phantom, i.e. non-self-avoiding, membranes. The critical behaviour of both isotropic and anisotropic polymerized membranes are studied using a nonperturbative renormalization group approach (NPRG). This allows for the investigation of the phase transitions and the low temperature flat phase in any internal dimension D and embedding d. Interestingly, graphene behaves just as a polymerized membrane in its flat phase.

  19. The tempered polymerization of human neuroserpin.

    Directory of Open Access Journals (Sweden)

    Rosina Noto

    Full Text Available Neuroserpin, a member of the serpin protein superfamily, is an inhibitor of proteolytic activity that is involved in pathologies such as ischemia, Alzheimer's disease, and Familial Encephalopathy with Neuroserpin Inclusion Bodies (FENIB. The latter belongs to a class of conformational diseases, known as serpinopathies, which are related to the aberrant polymerization of serpin mutants. Neuroserpin is known to polymerize, even in its wild type form, under thermal stress. Here, we study the mechanism of neuroserpin polymerization over a wide range of temperatures by different techniques. Our experiments show how the onset of polymerization is dependent on the formation of an intermediate monomeric conformer, which then associates with a native monomer to yield a dimeric species. After the formation of small polymers, the aggregation proceeds via monomer addition as well as polymer-polymer association. No further secondary mechanism takes place up to very high temperatures, thus resulting in the formation of neuroserpin linear polymeric chains. Most interesting, the overall aggregation is tuned by the co-occurrence of monomer inactivation (i.e. the formation of latent neuroserpin and by a mechanism of fragmentation. The polymerization kinetics exhibit a unique modulation of the average mass and size of polymers, which might suggest synchronization among the different processes involved. Thus, fragmentation would control and temper the aggregation process, instead of enhancing it, as typically observed (e.g. for amyloid fibrillation.

  20. Characterization behavior of some polymeric composite ion exchangers

    International Nuclear Information System (INIS)

    El-Zahhar, A.A; Ahdel-Aziz, H.M.; Siyam, T.

    2005-01-01

    Polymeric composite resins were prepared by template polymerization process in aqueous solution. Thermogravimetric analysis (TGA), differential thermal analysis (DTA) and The X-ray diffraction patterns (XRD) were performed to evaluate the physico chemical properties of the different polymeric composite resins. The TGA and DTA clarify high thermal stability of prepared polymeric composite resins. XRD of prepared polymeric composite shows that there is crystalline structure of some resins while other are amorphous one

  1. Plasma turbulence

    International Nuclear Information System (INIS)

    Horton, W.

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates

  2. Fabrication and properties of poly(polyethylene glycol n-alkyl ether vinyl ether)s as polymeric phase change materials

    International Nuclear Information System (INIS)

    Pei, Dong-fang; Chen, Sai; Li, Shu-qin; Shi, Hai-feng; Li, Wei; Li, Xuan; Zhang, Xing-xiang

    2016-01-01

    A series of poly(polyethylene glycol n-alkyl ether vinyl ether)s (PC m E n VEs) with various lengths of alkyl chains and polyethylene glycol spacers as side chain (m = 16,18; n = 1,2) were synthesized via two steps. First, monomers-ethylene glycol hexadecyl ether vinyl ether (C 16 E 1 VE), ethylene glycol octadecyl ether vinyl ether (C 18 E 1 VE), diethylene glycol hexadecyl ether vinyl ether (C 16 E 2 VE) and diethylene glycol octadecyl ether vinyl ether (C 18 E 2 VE) were synthesized by a modified Williamson etherification. Then, four new types of phase change materials were successfully fabricated by a living cationic polymerization. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) were employed to characterize their composition, thermal properties and crystallization behavior. The results show that, the side chains of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are in a hexagonal lattice, and the onset temperatures for melting of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are 39.8 °C, 37.4 °C, 51.0 °C and 48.9 °C, the onset temperatures for crystallization are 36.7 °C, 35.2 °C, 47.4 °C and 46.3 °C, respectively. The enthalpy changes of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 100 J/g; on the contrary, it is 96 J/g for PC 16 E 1 VE. The enthalpy decrease is no more than 11% after 10 heating and cooling cycles. The 5 wt% mass loss temperatures of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 300 °C; on the contrary, it’s 283 °C for PC 16 E 1 VE. Using a weak polarity, flexible alkyl ether chain (-OCH 2 CH 2 O-) as a spacer to link the main chain and side chain is conducive to the crystallization of the alkyl side chain. These new phase change materials can be applied in heat storage, energy conservation, and environmental protection.

  3. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    to 1990 with only 31 papers per year on average, and a total of some 1300 papers, precedes a considerable growth of some 35-50% in research activity every five years, over the last 20 years or so. As shown in the table, the annual dissemination of the field is more than 1600 papers and the total number of papers is in excess of 20000. This upwards trajectory is typical of a strong and growing subject area in physical science, with considerable capacity in both fundamental science and applications. PeriodNumber of papersPapers per annum 1948-1990130031 1991-19952279456 1996-20003447689 2001-20054571914 2006-201066401328 2011 1658 In many of the dense plasma jets discussed above, strong physical forces generated by the plasma are often desired and this favours plasma generation at elevated gas pressure, including atmospheric pressure, which favours a high level of gas ionization. Historically it has been challenging to reduce and control the strong physical forces in high-pressure plasmas for applications where these are unwanted, for example, surface modification of polymeric sheets [5]. Indeed, there is a real need for a vast range of material processing applications at temperatures below 100oC (or below 400 K) and this favours atmospheric-pressure plasma jets sustained far from thermal equilibrium with the dissipated electrical energy largely used not in heat generation but in unleashing non-equilibrium chemical reactions. The long-standing difficulty of effectively controlling the level of gas ionization at atmospheric pressure was overcome by the technological breakthrough of achieving atmospheric-pressure glow discharges in the late 1980s [6]. A related challenge stemming from high collisionality of atmospheric-pressure plasmas (v >> ω0) means that large-area plasmas sustained between parallel-plate electrodes are very susceptible to strong plasma instabilities when molecular gases are introduced for processing applications. This led to an effective

  4. Tamoxifen-loaded polymeric micelles: preparation, physico-chemical characterization and in vitro evaluation studies.

    Science.gov (United States)

    Cavallaro, Gennara; Maniscalco, Laura; Licciardi, Mariano; Giammona, Gaetano

    2004-11-20

    Several samples of polymeric micelles, formed by amphiphilic derivatives of PHEA, obtained by grafting into polymeric backbone of PEGs and/or hexadecylamine groups (PHEA-PEG-C(16) and PHEA-C(16)) and containing different amount of Tamoxifen, were prepared. All Tamoxifen-loaded polymeric micelles showed to increase drug water solubility. TEM studies provided evidence of the formation of supramolecular core/shell architectures containing drug, in the nanoscopic range and with spherical shape. Samples with different amount of encapsulated Tamoxifen were subjected to in vitro cytotoxic studies in order to evaluate the effect of Tamoxifen micellization on cell growth inhibition. All samples of Tamoxifen-loaded polymeric micelles showed a significantly higher antiproliferative activity in comparison with free drug, probably attributable to fluidification of cellular membranes, caused by amphiphilic copolymers, that allows a higher penetration of the drug into tumoral cells. To gain preliminary information about the potential use of prepared micelles as Tamoxifen drug delivery systems, studies evaluating drug release ability of micelle systems in media mimicking biological fluids (buffer solutions at pH 7.4 and 5.5) and in human plasma were carried out. These studies, performed evaluating the amount of Tamoxifen that remains in solution as a function of time, showed that at pH 7.4, as well as in plasma, PHEA-C(16) polymeric micelles were able to release lower drug amounts than PHEA-PEG(5000)-C(16) ones, while at pH 5.5, the behavior difference between two kind of micelles was less pronounced.

  5. Genotoxic evaluation of polymeric nanoparticles

    Directory of Open Access Journals (Sweden)

    Tamara Iglesias Alonso

    2015-06-01

    Full Text Available An important strategy for optimizing the therapeutic efficacy of many conventional drugs is the development of polymeric nanoparticles (NPs, as it may expand their activities, reduce their toxicity, increase their bioactivity and improve biodistribution. The main objective of this study was to evaluate the genotoxicity of 8 different poly (anhydride NPs designed for the oral administration of therapeutic compounds by using the comet assay in combination with the enzyme formamidopypiridine DNA-glycosylase (FPG. Furthermore, the mitogen capacity of the NPs was evaluated by the proliferation assay. All NPs were tested at four concentrations (0, 0.5, 1 and 2 mg/mL in Caco-2 cells after 3 hours of treatment while selected NPs were also tested after 24 h. The comet assay was performed immediately after the treatment and cell proliferation was assessed by counting the treated cells after their incubation at 37 °C for 48h. Cells treated with 1 µM of the photosensitizer Ro 19-8022 plus 5 min of light, as well as cells treated with 100 µM H2O2 were included as positive controls in all the experiments. All NPs studied did not result in any increase in the frequency of strand breaks or alkali-labile sites in Caco-2 cells but they induced a slight concentration-dependent increase in net FPG sensitive sites (oxidized and/or alkylated bases. Furthermore, treated cells did not show changes in levels of proliferation in comparison with the negative control.

  6. Plasma properties

    International Nuclear Information System (INIS)

    Weitzner, H.

    1990-06-01

    This paper discusses the following topics: MHD plasma activity: equilibrium, stability and transport; statistical analysis; transport studies; edge physics studies; wave propagation analysis; basic plasma physics and fluid dynamics; space plasma; and numerical methods

  7. Survey and research on precision polymerization polymeric materials; Seimitsu jugo kobunshi zairyo ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Survey and research on the precision control of primary structure of polymeric materials and the precision evaluation technology have been conducted to develop advanced polymeric materials. It is proposed that the three basic processes of polymer synthesis, i.e., addition, condensation, and biomimesis, in forming the precision polymerization skeleton are to be covered through a centralized joint research effort with participation of industry, academia, and the government institute and under the leadership of researchers from academic institutions as the team leaders. For the study of technology trends, international conferences held in UK, Germany, and Hawaii are introduced, and domestic meetings, i.e., Annual Polymer Congress and Polymer Conference, are summarized. In addition, Precision Polymerization Forum and International Workshop on Precision Polymerization were held. The basic studies include a quantum-chemical elucidation of the elementary process in polymerization reaction, time-resolved analysis of polymerization process and polymer properties, synthesis of polymers with controlled microstructures by coordination polymerization using metal complexes, synthesis of polymer with controlled microstructures by precision polycondensation, molecular recognition in catalyst-reaction site, and synthesis of imprinting polymers. 246 refs., 117 figs., 14 tabs.

  8. Bone marrow transplantation: Effects of conditioning and cyclosporin prophylaxis on microvascular permeability to a small solute (technetium 99m diethylene triamine penta-acetic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M. (Royal Postgraduate Medical School, London (UK). Dept. of Diagnostic Radiology); Vassilarou, D.S.; Hows, J.M. (Royal Postgraduate Medical School, London (UK). Dept. of Haematology); Ballardie, F.W. (Royal Postgraduate Medical School, London (UK). Dept. of Medicine)

    1991-03-01

    Microvascular permeability to small diffusible solutes has rarely been measured at a clinical level. We have developed a simple non-invasive technique for measuring the permeability surface area (PS) product, which is suitable for clinical use. We illustrate its potential value in six subjects who underwent bone marrow transplantation for chronic myeloid leukaemia. These patients received high-dose cyclosporin A (CyA) for prevention of graft versus host disease (GVHD) and sustained an easily measurable increase in microvascular permeability to technetium 99m diethyl triamine penta-acetic acid ({sup 99m}Tc-DTPA). This was measured as the PS product, which increased from 1.1 (SD 0.3) to 2.2 (0.4) ml/min per 100 ml tissue between baseline and treatment with CyA for prevention of GVHD (P < 0.01). The increase broadly correlated with nephrotoxicity which was measured, from the plasma DTPA clearance, as global glomerular filtration rate (GFR). This decreased from 106 (11.1) to 49 (6.7) ml/min (P < 0.001). These abnormalities, both in PS product and GFR, were sustained for several months, after which they tended to return towards baseline levels. We conclude firstly that this technique has a potential clinical role and secondly that endothelial abnormalities due to CyA deserve further study. (orig.).

  9. Plasma accelerators

    International Nuclear Information System (INIS)

    Bingham, R.; Angelis, U. de; Johnston, T.W.

    1991-01-01

    Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating gradients. Starting with the plasma beat wave accelerator (PBWA) and laser wakefield accelerator (LWFA) schemes and the plasma wakefield accelerator (PWFA) steady progress has been made in theory, simulations and experiments. Computations are presented for the study of LWFA. (author)

  10. Polymerization of N-(fluoro phenyl) maleimides

    International Nuclear Information System (INIS)

    Barrales-Rienda, J.M.; Ramos, J.G.; Chaves, M.S.

    1979-01-01

    Poly(N-aryl maleimide)s of characteristic structures have been synthesized and some of their physical properties studied. The polymerization of N-(fluoro phenyl) maleimides by free-radical initiation in bulk or in solution and by anionic catalyst have been studied to compare the characteristics of polymerization by γ-ray irradiation with that by free-radical initiation. The polymers were characterized by elemental analysis, intrinsic viscosity, spectroscopy (IR and NMR), programmed thermogravimetric analysis, and x-ray diffraction. Spectra of polymers prepared by radiation and anionic polymerization were nearly identical with those of polymers prepared by free-radical polymerization initiated by azobisisobutyronitrile in bulk or in solution and by the self-initiated thermal polymerization. A variety of reaction conditions were tried, but all attempts to change the molecular structure of the polymers were unsuccessful. Rates of thermal degradation for poly[N-(fluoro phenyl) maleimide]s have been analyzed by using a multiple-heating-rate procedure. Overall activation energy, order of reaction, and frequency factor have been evaluated. 6 figures, 8 tables

  11. Electrospun polymeric nanofibers for transdermal drug delivery

    Directory of Open Access Journals (Sweden)

    Mahya Rahmani

    2017-04-01

    Full Text Available Conventional transdermal drug delivery systems (TDDS have been designed for drug delivery through the skin. These systems use the permeability property of stratum corneum, the outermost surface layer of the skin. Applying polymeric micro and nanofibers in drug delivery has recently attracted great attention and the electrospinning technique is the preferred method for polymeric micro-nanofibers fabrication with a great potential for drug delivery. More studies in the field of nanofibers containing drug are divided two categories: first, preparation and characterization of nanofibers containing drug and second, investigation of their therapeutic applications. Drugs used in electrospun nanofibers can be categorized into three main groups, including antibiotics and antimicrobial agents, anti-inflammatory agents and vitamins with therapeutic applications. In this paper, we review the application of electrospun polymeric scaffolds in TDDS and also introduce several pharmaceutical and therapeutic agents which have been used in polymer nanofibrous patches.

  12. Biomimetic polymeric membranes for water treatment

    DEFF Research Database (Denmark)

    Habel, Joachim Erich Otto

    This project is about the interplay of the three major components of aquaporin based biomimetic polymeric membranes (ABPMs): Aquaporins (AQPs), amphiphilic block copolymers, serving as a vesicular matrix for the hydrophobic AQP exterior (proteopolymersomes) and a polymeric membrane as embedment....... The interplay of proteopolymersomes and polymeric mesh support (in this case polyethersulfone, PES) was examined via integration of proteopolymersomes in an active layer (AL) formed by interfacial polymerisation between a linker molecule in aqueous phase and another in organic phase on top of the PES....... The resulting thin-film composite (TFC) membrane was analyzed via cross-flow forward osmosis (FO), scanning electron microscopy (SEM), fourier-transformed infrared spectroscopy (FTIR), as well as in the non-supported form over FTIR and a specialized microfluidic visualization approach. Where no clear dierences...

  13. Cross-linking of polymeric materials

    International Nuclear Information System (INIS)

    Bloom, L.I.; Du Plessis, T.A.; Meij, G.O.

    1991-01-01

    The invention provides a method of producing a cured polymeric artifact from a polymeric thermoplastic starting material, the material of the artifact having reduced thermoplasticity relative to the starting material and exhibiting an enhanced degree of cross-linking relative to the starting material. The method includes subjecting a polymeric thermoplastic starting material, which is capable of being cross-linked by irradiation, to sufficient irradiation partially to cross-linked the starting material to produce a thermoplastic partially cross-linked intermediate material. The thermoplasticity of the intermediate material is then reduced by heating it to raise its melting point. The invention also provides a method of making a partially cross-linked feedstocks and a master batch for use in making such artifacts

  14. Laser microstructuring for fabricating superhydrophobic polymeric surfaces

    Science.gov (United States)

    Cardoso, M. R.; Tribuzi, V.; Balogh, D. T.; Misoguti, L.; Mendonça, C. R.

    2011-02-01

    In this paper we show the fabrication of hydrophobic polymeric surfaces through laser microstructuring. By using 70-ps pulses from a Q-switched and mode-locked Nd:YAG laser at 532 nm, we were able to produce grooves with different width and separation, resulting in square-shaped pillar patterns. We investigate the dependence of the morphology on the surface static contact angle for water, showing that it is in agreement with the Cassie-Baxter model. We demonstrate the fabrication of a superhydrophobic polymeric surface, presenting a water contact angle of 157°. The surface structuring method presented here seems to be an interesting option to control the wetting properties of polymeric surfaces.

  15. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A method is described for electron beam heating of a high-density plasma to drive a fast liner. An annular or solid relativistic electron beam is used to heat a plasma to kilovolt temperatures through streaming instabilities in the plasma. Energy deposited in the plasma then converges on a fast liner to explosively or ablatively drive the liner to implosion. (U.K.)

  16. Inflation and Instability of a Polymeric Membrane

    DEFF Research Database (Denmark)

    Neergaard, Jesper; Hassager, Ole

    1999-01-01

    We consider an axisymmetric polymeric membrane inflated by a uniform pressure difference acting across the membrane. The polymeric materialis described by an arbitrary combination of a viscoelastic and a purely viscous component to the stress. Some viscoelastic materials described by a Mooney......-Rivlin model show a monotone increasingpressure during inflation of a spherical membrane. These materials develop a homogeneous membrane thickness in agreement with the Considere-Pearson condition. Molecularly based models such as the neo-Hookean, Doi-Edwards or Tom-Pom model show a pressure maximum when...... inflated. Membranesdescribed by these models develop a local thinning of the membrane which may lead to bursting in finite time....

  17. Polymeric materials obtained by electron beam irradiation

    International Nuclear Information System (INIS)

    Dragusin, M.; Moraru, R.; Martin, D.; Radoiu, M.; Marghitu, S.; Oproiu, C.

    1995-01-01

    Research activities in the field of electron beam irradiation of monomer aqueous solution to produce polymeric materials used for waste waters treatment, agriculture and medicine are presented. The technologies and special features of these polymeric materials are also described. The influence of the chemical composition of the solution to ba irradiated, absorbed dose level and absorbed dose rate level are discussed. Two kinds of polyelectrolytes, PA and PV types and three kinds of hydrogels, pAAm, pAAmNa and pNaAc types, the production of which was first developed with IETI-10000 Co-60 source and then adapted to the linacs built in Accelerator Laboratory, are described. (author)

  18. Mechanism and kinetics of addition polymerizations

    CERN Document Server

    Kucera, M

    1991-01-01

    This volume presents an up-to-date survey of knowledge concerning addition type polymerizations. It contains nine chapters, each of which covers a particular basic term. Whenever necessary, the phenomena are discussed from the viewpoint of both stationary and non-stationary state of radical, ionic (i.e. anionic and cationic) and coordination polymerization. Special attention has been paid to the propagation process. It provides not only a general overview but also information on important special cases (theoretical conditions of propagation, influence of external factors, controlled propagatio

  19. Polymeric matrix materials for infrared metamaterials

    Science.gov (United States)

    Dirk, Shawn M; Rasberry, Roger D; Rahimian, Kamyar

    2014-04-22

    A polymeric matrix material exhibits low loss at optical frequencies and facilitates the fabrication of all-dielectric metamaterials. The low-loss polymeric matrix material can be synthesized by providing an unsaturated polymer, comprising double or triple bonds; partially hydrogenating the unsaturated polymer; depositing a film of the partially hydrogenated polymer and a crosslinker on a substrate; and photopatterning the film by exposing the film to ultraviolet light through a patterning mask, thereby cross-linking at least some of the remaining unsaturated groups of the partially hydrogenated polymer in the exposed portions.

  20. Plasma Modes

    Science.gov (United States)

    Dubin, D. H. E.

    This chapter explores several aspects of the linear electrostatic normal modes of oscillation for a single-species non-neutral plasma in a Penning trap. Linearized fluid equations of motion are developed, assuming the plasma is cold but collisionless, which allow derivation of the cold plasma dielectric tensor and the electrostatic wave equation. Upper hybrid and magnetized plasma waves in an infinite uniform plasma are described. The effect of the plasma surface in a bounded plasma system is considered, and the properties of surface plasma waves are characterized. The normal modes of a cylindrical plasma column are discussed, and finally, modes of spheroidal plasmas, and finite temperature effects on the modes, are briefly described.

  1. Sterilization by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Adir Jose; Mansano, Ronaldo Domingues; Andreoli Pinto, Terezinha de Jesus; Ruas, Ronaldo; Silva Zambon, Luis da; Silva, Monica Valero da; Verdonck, Patrick Bernard

    2004-07-31

    The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy.

  2. Immobilization of biocatalysts for enzymatic polymerizations : Possibilities, advantages, applications

    NARCIS (Netherlands)

    Miletic, Nemanja; Nastasovic, Aleksandra; Loos, Katja; Miletić, Nemanja; Nastasović, Aleksandra

    Biotechnology also holds tremendous opportunities for realizing functional polymeric materials. Biocatalytic pathways to polymeric materials are an emerging research area with not only enormous scientific and technological promise, but also a tremendous impact on environmental issues. Many of the

  3. Polymerization Initiated at the Sidewalls of Carbon Nanotubes

    Science.gov (United States)

    Tour, James M.; Hudson, Jared L.

    2011-01-01

    A process has been developed for growing polymer chains via anionic, cationic, or radical polymerization from the side walls of functionalized carbon nanotubes, which will facilitate greater dispersion in polymer matrices, and will greatly enhance reinforcement ability in polymeric material.

  4. Interfacial Polymerization of Polyaniline Nanofibers Grafted to Au Surfaces

    National Research Council Canada - National Science Library

    Sawall, D

    2004-01-01

    .... The in-situ polymerization technique of these PANI nanofibers in the presence of sulfonated polystyrene allowed for the growth of PANI 2-D nanostructures embedded in the polymerized sulfonated host...

  5. PLASMA POLYMER FILMS AS ADHESION PROMOTING PRIMERS FOR ALUMINUM. PART II: STRENGTH AND DURABILITY OF LAP JOINTS

    Science.gov (United States)

    Plasma polymerized hexamethyldisiloxane (HMDSO) films (~800 A in thickness) were deposited onto 6111-T4 aluminum substrates in radio frequency and microwave powered reactors and used as primers for structural adhesive bonding. Processing variables such as substrate pre-treatment,...

  6. Vibrating polymeric microsieves: Antifouling strategies for microfiltration

    NARCIS (Netherlands)

    Girones nogue, Miriam; Akbarsyah, Imam J.; Bolhuis-Versteeg, Lydia A.M.; Lammertink, Rob G.H.; Wessling, Matthias

    2006-01-01

    Constant flux performance in time is achieved with polyethersulfone (PES) polymeric microsieves when filtering protein solutions, skimmed milk and white beer in combination with backpulsing. Such microsieves are fabricated by phase separation micromolding (PSμM) and possess pores around 2 μm. The

  7. Inflation and Failure of Polymeric Membranes

    DEFF Research Database (Denmark)

    Hassager, Ole; Neergaard, Jesper

    2000-01-01

    We consider the inflation of an axisymmetric polymeric membrane.Some membranes composed of viscoelastic materialsdescribed by a Mooney-Rivlin model show a monotone increasingpressure during inflation. These materialsdevelop a homogeneous membrane thickness in agreement with the Considere...... is found to stabilize the inflated polymer membrane....

  8. Gamma Radiation-Induced Template Polymerization Technique

    International Nuclear Information System (INIS)

    Siyam, T.

    2005-01-01

    Gamma radiation induced copolymerization of acrylamide sodiumacrylate (AM-AANa) in the presence and absence of the polymer additive was studied at low monomer concentration(1.4M/l). The results showed that the exponents of the dose rate for the polymerization rate was found to be 1.3 and 1.4 in the absence and in the presence of the polymer additive respectively. The molecular weight of the formed polymer increased by addition of the polymer to the system. In the presence of the polymer the comonomers polymerize on the added polymer. In the absence of the added polymer the comonomers polymerize according to the copolymerization process at the initial stage of the copolymerization. While at high conversion the residual comonomers polymerize on the formed macromolecular chains of the produced polymer. These studies showed that the copolymerization in the presence of added polymer is completely template copolymerization while in the absence of the polymer the copolymerization process is only template process with a high conversion

  9. Polymerization of epoxidized triglycerides with fluorosulfonic acid

    Science.gov (United States)

    The use of triglycerides as agri-based renewable raw materials for the development of new products is highly desirable in view of uncertain future petroleum prices. A new method of polymerizing epoxidized soybean oil has been devised with the use of fluorosulfonic acid. Depending on the reaction con...

  10. On viscoelastic instability in polymeric filaments

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Koblitz; Hassager, Ole

    1999-01-01

    The 3D Lagrangian Integral Method is used to simulate the effects of surface tension on the viscoelastic end-plate instability, occuring in the rapid extension of some polymeric filaments between parallel plates. It is shovn that the surface tension delays the onset of the instability. Furthermore...

  11. Polymeric additive performance in closed whitewater systems

    Science.gov (United States)

    T. H. Wegner

    1984-01-01

    “With more stringent requirements on discharge water quality and with escalating water treatment costs, water recycling within the paper mill is of growing importance. A serious problem resulting from more white-water recycling is reduced drainage and fiber or fines retention because of diminished polymeric additive performance. To provide better insight for overcoming...

  12. Latent tracks in polymeric etched track detectors

    International Nuclear Information System (INIS)

    Yamauchi, Tomoya

    2013-01-01

    Track registration properties in polymeric track detectors, including Poly(allyl diglycol carbonate), Bispenol A polycarbonate, Poly(ethylen terephtarate), and Polyimide, have been investigated by means of Fourie transform Infararede FT-IR spectrometry. Chemical criterion on the track formation threshold has been proposes, in stead of the conventional physical track registration models. (author)

  13. Bioactive Polymeric Materials for Tissue Repair

    Directory of Open Access Journals (Sweden)

    Diane R. Bienek

    2017-01-01

    Full Text Available Bioactive polymeric materials based on calcium phosphates have tremendous appeal for hard tissue repair because of their well-documented biocompatibility. Amorphous calcium phosphate (ACP-based ones additionally protect against unwanted demineralization and actively support regeneration of hard tissue minerals. Our group has been investigating the structure/composition/property relationships of ACP polymeric composites for the last two decades. Here, we present ACP’s dispersion in a polymer matrix and the fine-tuning of the resin affects the physicochemical, mechanical, and biological properties of ACP polymeric composites. These studies illustrate how the filler/resin interface and monomer/polymer molecular structure affect the material’s critical properties, such as ion release and mechanical strength. We also present evidence of the remineralization efficacy of ACP composites when exposed to accelerated acidic challenges representative of oral environment conditions. The utility of ACP has recently been extended to include airbrushing as a platform technology for fabrication of nanofiber scaffolds. These studies, focused on assessing the feasibility of incorporating ACP into various polymer fibers, also included the release kinetics of bioactive calcium and phosphate ions from nanofibers and evaluate the biorelevance of the polymeric ACP fiber networks. We also discuss the potential for future integration of the existing ACP scaffolds into therapeutic delivery systems used in the precision medicine field.

  14. Hyaluronan polymeric micelles for topical drug delivery

    Czech Academy of Sciences Publication Activity Database

    Šmejkalová, D.; Muthný, T.; Nešporová, K.; Hermannová, M.; Achbergerová, E.; Huerta-Angelesa, G.; Marek Svoboda, M.; Čepa, M.; Machalová, V.; Luptáková, Dominika; Velebný, V.

    2017-01-01

    Roč. 156, JAN 20 (2017), s. 86-96 ISSN 0144-8617 Institutional support: RVO:61388971 Keywords : Skin penetration * Polymeric micelle * Hyaluronan Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 4.811, year: 2016

  15. The Morphology of Emulsion Polymerized Latex Particles

    Science.gov (United States)

    Wignall, G. D.; Ramakrishnan, V. R.; Linne, M. A.; Klein, A.; Sperling, L. H.; Wai, M. P.; Gelman, R. A.; Fatica, M. G.; Hoerl, R. H.; Fisher, L. W.

    1987-11-01

    Under monomer starved feed conditions, emulsion polymerization of perdeuterated methyl methacrylate and styrene in the presence of preformed polymethylmethacrylate latexes resulted in particles with a core-shell morphology, as determined by small-angle neutron scattering (SANS) analysis for a hollow sphere. The locus of polymerization of the added deuterated monomer is therefore at the particle surface. In similar measurements a statistical copolymer of styrene and methyl methacrylate was used as seed particles for further polymerization of trideuteromethyl methacrylate. The resulting polymer latex was again shown to have a core-shell morphological structure as determined by SANS. SANS experiments were also undertaken on polystyrene latexes polymerized by equilibrium swelling methods, with deuterated polymer forming the first or second step. The experiments covered a molecular weight range of 6 x 10{sup 4} 10{sup 6} the molecular weights are consistent with the experimental errors, indicating that the deuterium labeled molecules are randomly distributed in the latex. These results led to the finding that the polymer chains were constrained in the latex particles by factors of 2 to 4 from the relaxed coil dimensions. For M molecules. Several models were examined, including the possible development of core-shell structures at lower molecular weights.

  16. Pressure-induced polymerization of phenoxyethyl acrylate

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, K; Wrzalik, R; Paluch, M; Ziolo, J [Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice (Poland); Roland, C M [Naval Research Laboratory, Chemistry Division, Code 6120, Washington, DC 20375-5342 (United States)

    2008-06-18

    Polymerization of phenoxyethyl acrylate was induced without catalyst or initiators by the application of hydrostatic pressure at elevated temperature. Broadband dielectric and infrared spectroscopy were employed to follow the course of the reaction, which reached a degree of conversion of 60%. The structure of the obtained polymer was determined from density functional theory calculations.

  17. Immobilization of Trichoderma reesei by radiation polymerization

    International Nuclear Information System (INIS)

    Zhou Ruimin; Ma Zueteh; Kaetus, Isao; Kumakura, Minoro

    1993-01-01

    Immobilization of Trichoderma reesei was carried out by radiation polymerization. It was found that the activity of fixed cells increased with increasing surface area of the carrier and was affected by the concentration of monomer tetraethylenglycol dimethacrylate and the shape of the substrate composition and structure of cotton textile fabrics. (author)

  18. Polymerization of different lignins by laccase

    NARCIS (Netherlands)

    Mattinen, M.L.; Suortti, T.; Gosselink, R.J.A.; Argyropoulos, D.S.; Evtuguin, D.; Suurnäkki, A.; Jong, de E.; Tamminen, T.

    2008-01-01

    In this study the oxidative polymerization of different lignins, i.e. Flax Soda lignin, Spruce EMAL, and Eucalyptus Dioxane lignin by Trametes hirsuta laccase was compared. Initially the structures of the different lignins were compared by Fourier transform infrared spectroscopy. The reactivity of

  19. Interaction of acetamiprid with extracellular polymeric substances ...

    African Journals Online (AJOL)

    Extracellular polymeric substances (EPS) are important components of activated sludge and it plays an important role in removing pollutants. The interaction between EPS and organic pollutants is still little known. In the present study, the interaction of soluble/bound EPS with acetamiprid, a neonicotinoid insecticide, was ...

  20. Radiation sterilization of polymeric implant materials

    International Nuclear Information System (INIS)

    Bruck, S.D.; Mueller, E.P.

    1988-01-01

    High-energy irradiation sterilization of medical devices and implants composed of polymeric biomaterials that are in contact with tissue and/or blood, may adversely affect their long-term mechanical and/or biological performance (tissue and/or blood compatibility). Since many polymeric implants may contain trace quantities of catalysts and/or other additives, the effect of high-energy radiation on these additives, and possible synergistic effects with the polymer chains under the influence of high-energy radiation, must be considered. It is essential to indicate whether polymeric implants are used in short-term (acute) or long-term (chronic) applications. Relatively small changes in their physicochemical, mechanical, and biological properties may be tolerable in the short term, whereas similar changes may lead to catastrophic failures in long-term applications. Therefore, polymeric implants which are to be sterilized by high-energy irradiation should be carefully evaluated for long-term property changes which may be induced by the radiation

  1. Ion induced polymerization in benzene frozen films

    Energy Technology Data Exchange (ETDEWEB)

    Calcagno, G [Catania Univ. (Italy). Ist. di Fisica; Strazzulla, G [Catania Univ. (Italy). Osservatorio Astrofisico; Fichera, M; Foti, G [Catania Univ. (Italy). Ist. di Radiologia

    1983-07-01

    The cross section of the polymerization process induced by energetic protons colliding with frozen benzene layers has been measured. The results have been described by a simple theory and they show that the process is a volume one occurring along the ion track and interesting all of the crossed layers.

  2. Vinyl acetate polymerization by ionizing radiation

    International Nuclear Information System (INIS)

    Mesquita, Andrea Cercan

    2002-01-01

    The aim of this work is the synthesis and characterization of the poly(vinyl acetate) using the ionizing radiation. Six polymerizations of vinyl acetate were carried out using three techniques of polymerization: in bulk, emulsion and solution. In the technique of solution polymerization were used two solvents, the alcohol ethyl and the methylethylketone, in two proportions 1:0.5 and 1:1 related to the monomer. The solutions were irradiated with gamma rays from a 60 Co source, with dose rate between 5.25 kGy/h and 6.26 kGy/h. The polymers obtained were characterized by Fourier Transform Infrared Spectroscopy (FTIR). The glass transition temperature (Tg) was investigated by Differential Scanning Calorimeter (DSC). The molecular weight was analyzed by the technique of Gel Permeation Chromatography (GPC). Tests of density, hardness and Vicat softening temperature were carried out. The infrared spectroscopy and others results confirmed that the polymers obtained by polymerization of vinyl acetate in bulk, emulsion and solution, using ionizing radiation, really correspond at poly(vinyl acetate). (author)

  3. Microfluidic production of polymeric micro- and nanoparticles

    NARCIS (Netherlands)

    Serra, C.; Kahn, I.U.; Cortese, B.; Croon, de M.H.J.M.; Hessel, V.; Ono, T.; Anton, N.; Vandamme, Th.

    2013-01-01

    Polymeric micro- and nanoparticles have attracted a wide attention of researchers in various areas such as drug delivery, sensing, imaging, cosmetics, diagnostics, and biotechnology. However, processes with conventional equipment do not always allow a precise control of their morphology, size, size

  4. Characteristic emission in glutaraldehyde polymerized hemoglobin

    International Nuclear Information System (INIS)

    Ma Li; Wang Xiaojun

    2011-01-01

    Hemoglobin with different modifications has been investigated using spectroscopic techniques. A new emission at around 371 nm has been observed under excitation of 305 nm from glutaraldehyde polymerized human hemoglobin. Intensity and peak position of the emission are dependent on both oxidation state and ligand environment and the emission has been identified from the hemoglobin oligomer.

  5. Carboxyl-Functionalized Polymeric Microspheres Prepared by One-Stage Photoinitiated RAFT Dispersion Polymerization

    Directory of Open Access Journals (Sweden)

    Jianbo Tan

    2017-12-01

    Full Text Available Herein, we report a photoinitiated reversible addition-fragmentation chain transfer (RAFT dispersion copolymerization of methyl methacrylate (MMA and methyl methacrylic (MAA for the preparation of highly monodisperse carboxyl-functionalized polymeric microspheres. High rates of polymerization were observed, with more than 90% particle yields being achieved within 3 h of UV irradiation. Effects of reaction parameters (e.g., MAA concentration, RAFT agent concentration, photoinitiator concentration, and solvent composition were studied in detail, and highly monodisperse polymeric microspheres were obtained in most cases. Finally, silver (Ag composite microspheres were prepared by in situ reduction of AgNO3 using the carboxyl-functionalized polymeric microspheres as the template. The obtained Ag composite microspheres were able to catalyze the reduction of methylene blue (MB with NaBH4 as a reductant.

  6. SYNTHESIS OF BLOCK COPOLYMER BY INTEGRATED LIVING ANIONIC POLYMERIZATION-ATOM TRANSFER RADICAL POLYMERIZATION (ATRP)

    Institute of Scientific and Technical Information of China (English)

    Bing Liu; Feng Liu; Ning Luo; Sheng-kang Ying; Qing Liu

    2000-01-01

    Alpha-trichloroacetoxy terminated polystyrene oligomer (PS-CH2CH2OCOCCl3) and poly-(styrene-b-butadiene)oligomer [P(S-b-B)-CH2CH2OCOCCl3)] were synthesized by living anionic polymeri-zation using n-butyllithium as initiator.Then the PS-CH2CH2OCOCCl3 (PS-Cl3) or P(S-b-B)-CH2CH2O-COCCl3 (PSB-Cl3) was used as the macroinitiator in the polymerization of (meth)acrylates in the presence of CuX/bpy. AB diblock and ABC triblock copolymers were prepared by the integrated living anionic polymerization (LAP)-atom transfer radical polymerization (ATRP). The structures of the PSB-Cl3 and the P(S-b-MMA) were identified by FTIR and 1H-NMR spectrum, respectively. A new way to design block copolymers (the combination of LAP and ATRP) was developed.

  7. TRANSITION METAL CATALYSIS IN CONTROLLED RADICAL POLYMERIZATION: ATOM TRANSFER RADICAL POLYMERIZATION. (R826735)

    Science.gov (United States)

    Novel and diversified macromolecular structures, which include polymers with designed topologies (top), compostions (middle), and functionalities (bottom), can be prepared by atom transfer radical polymerization processes. These polymers can be synthesized from a large variety of...

  8. Experimental study of living free radical polymerization using trifunctional initiator and polymerization mediated by nitroxide

    International Nuclear Information System (INIS)

    Galhardo, Eduardo; Lona, Liliane M.F.

    2009-01-01

    Controlled free radical polymerization or living free radical polymerization has received increasing attention as a technique for the production of polymers with microstructure highly controlled. In particular, narrow molecular weight distributions are obtained with polydispersity very close to one. In this research it was investigate the controlled polymerization mediated by nitroxide, using a cyclic trifunctional peroxide. As long as we know, there are only publications in literature dealing with NMRP using mono- and bi-functional initiators. It was believed that the trifunctional peroxide can increase the rate of polymerization, since more free radicals are generated, if compared with initiators with lower functionality. Furthermore, the fact of the initiator be cyclic means that branches are not generated in the chains, which theoretically prevents an increase in polydispersity of the polymer. The effect of the dissociation constant of the trifunctional initiator in the velocity of the reaction was analyzed. (author)

  9. 21 CFR 870.3650 - Pacemaker polymeric mesh bag.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

  10. FtsZ Polymerization Assays : Simple Protocols and Considerations

    NARCIS (Netherlands)

    Król, Ewa; Scheffers, Dirk-Jan

    2013-01-01

    During bacterial cell division, the essential protein FtsZ assembles in the middle of the cell to form the so-called Z-ring. FtsZ polymerizes into long filaments in the presence of GTP in vitro, and polymerization is regulated by several accessory proteins. FtsZ polymerization has been extensively

  11. Plasma centrifuges

    International Nuclear Information System (INIS)

    Karchevskij, A.I.; Potanin, E.P.

    2000-01-01

    The review of the most important studies on the isotope separation processes in the rotating plasma is presented. The device is described and the characteristics of operation of the pulse plasma centrifuges with weakly and strongly ionized plasma as well as the stationary plasma centrifuges with the medium weak ionization and devices, applying the stationary vacuum arc with the high ionization rate and the stationary beam-plasma discharge with complete ionization, are presented. The possible mechanisms of the isotope separation in plasma centrifuges are considered. The specific energy consumption for isotope separation in these devices is discussed [ru

  12. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  13. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  14. THE EFFECTS OF N-2-HYDROXYETHYL-N-METHYL-P-TOLUIDINE ON METHYL METHACRYLATE RADICAL POLYMERIZATION AND ACRYLONITRILE PHOTOINDUCED POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; ZHANG Zhanghua; FENG Xinde

    1992-01-01

    The effects of N-2-hydroxyethyl-N-methyl-p-toluidine (HMT) on MMA polymerization using organic peroxide as an initiator and on AN photoinduced polymerization have been investigated respectively. The kinetics of polymerization and the overall activation energy of polymerization were determined. Based on kinetics study and the end group analysis of the polymer obtained by UV spectrum method, the initiation mechanism is proposed.

  15. A theory for fracture of polymeric gels

    Science.gov (United States)

    Mao, Yunwei; Anand, Lallit

    2018-06-01

    A polymeric gel is a cross-linked polymer network swollen with a solvent. If the concentration of the solvent or the deformation is increased to substantial levels, especially in the presence of flaws, then the gel may rupture. Although various theoretical aspects of coupling of fluid permeation with large deformation of polymeric gels are reasonably well-understood and modeled in the literature, the understanding and modeling of the effects of fluid diffusion on the damage and fracture of polymeric gels is still in its infancy. In this paper we formulate a thermodynamically-consistent theory for fracture of polymeric gels - a theory which accounts for the coupled effects of fluid diffusion, large deformations, damage, and also the gradient effects of damage. The particular constitutive equations for fracture of a gel proposed in our paper, contain two essential new ingredients: (i) Our constitutive equation for the change in free energy of a polymer network accounts for not only changes in the entropy, but also changes in the internal energy due the stretching of the Kuhn segments of the polymer chains in the network. (ii) The damage and failure of the polymer network is taken to occur by chain-scission, a process which is driven by the changes in the internal energy of the stretched polymer chains in the network, and not directly by changes in the configurational entropy of the polymer chains. The theory developed in this paper is numerically implemented in an open-source finite element code MOOSE, by writing our own application. Using this simulation capability we report on our study of the fracture of a polymeric gel, and some interesting phenomena which show the importance of the diffusion of the fluid on fracture response of the gel are highlighted.

  16. NATO Advanced Study Institute on Ring-opening Metathesis Polymerization of Olefins and Polymerization of Alkynes

    CERN Document Server

    1998-01-01

    The first NATO Advanced Study Institute on Olefin Metathesis and Polymerization Catalysts was held on September 10-22, 1989 in Akcay, Turkey. Based on the fundamental research of RRSchrock, RGrubbs and K.B.Wagener in the field of ring opening metathesis polymerization (ROMP), acyclic diene metathesis (ADMET) and alkyne polymerization, these areas gained growing interest within the last years. Therefore the second NATO-ASI held on metathesis reactions was on Ring Opening Metathesis Po­ lymerization of Olefins and Polymerization of Alkynes on September 3-16, 1995 in Akcay, Turkey. The course joined inorganic, organic and polymer chemists to exchange their knowledge in this field. This volume contains the main and short lectures held in Akcay. To include ADMET reactions better into the title of this volume we changed it into: Metathesis Polymerization of Olefins and Alkyne Polymerization. This volume is addressed to research scientists, but also to those who start to work in the area of olefin metathesis and al...

  17. Research in Water Permeability of Poly(ethylene) Terephthalate Track Membranes Modified by Polymerization of Dimethylaniline under the Action of Direct Current Discharge

    CERN Document Server

    Kravets, L I; Drachev, A I

    2004-01-01

    The properties of poly(ethylene) terephthalate track membranes modified by polymerization of dimethylaniline in a discharge of direct current are investigated. The influence of conditions of plasma treatment on the basic characteristics of the membranes (pore size, wettability, surface charge, water permeability) is studied. It is shown that under the action of discharge, a polymeric layer is formed on the membrane surface that can swell in solutions with low pH values. It has been found that the degree of the swelling stipulated by the conformation transfer of macromolecules of the deposited polymeric layer depends upon the size of relative magnification of the mass of the membrane during its plasma treatment. It is also shown that the obtained membranes can reversibly react to changing the pH of solution and applied pressure.

  18. Antibiotic polymeric nanoparticles for biofilm-associated infection therapy.

    Science.gov (United States)

    Cheow, Wean Sin; Hadinoto, Kunn

    2014-01-01

    Polymeric nanoparticles are highly attractive as drug delivery vehicles due to their high structural integrity, stability during storage, ease of preparation and functionalization, and controlled release capability. Similarly, lipid-polymer hybrid nanoparticles, which retain the benefits of polymeric nanoparticles plus the enhanced biocompatibility and prolonged circulation time owed to the lipids, have recently emerged as a superior alternative to polymeric nanoparticles. Drug nanoparticle complex prepared by electrostatic interaction of oppositely charged drug and polyelectrolytes represents another type of polymeric nanoparticle. This chapter details the preparation, characterization, and antibiofilm efficacy testing of antibiotic-loaded polymeric and hybrid nanoparticles and antibiotic nanoparticle complex.

  19. Studies on Rate Enhancement of Polymerization in NMRP

    Institute of Scientific and Technical Information of China (English)

    HUANG Jian-ying; XU Miao-qing; YAN Ming-fa; CHEN Yi-hong; CHU Jia-yan; ZHUANG Jia-ming; DAI Li-zong; ZOU You-si

    2005-01-01

    In NMRP, the polymerization of MMA, the polymerization of St and the copolymerization of MMA with St were distinctly accelerated by the addition of a small amount of MN. The polymerization proceeds in a living fashion as indicated by the increase in molecular weight with the increase of time and conversion and a relatively low polydispersity. It has been found that the addition of MN results in a nearly one hundred times higher rate of the polymerization of MMA, a nearly twenty times higher rate of the polymerization of St and a nearly fifteen times higher rate of the copolymerization of St and MMA.

  20. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A method is described of providing electron beam heating of a high-density plasma to drive a fast liner to implode a structured microsphere. An annular relativistic electron beam is used to heat an annular plasma to kilovolt temperatures through streaming instabilities in the plasma. Energy deposited in the annular plasma then converges on a fast liner to explosively or ablatively drive the liner to convergence to implode the structured microsphere. (U.K.)

  1. Complex Macromolecular Architectures by Living Cationic Polymerization

    KAUST Repository

    Alghamdi, Reem D.

    2015-05-01

    Poly (vinyl ether)-based graft polymers have been synthesized by the combination of living cationic polymerization of vinyl ethers with other living or controlled/ living polymerization techniques (anionic and ATRP). The process involves the synthesis of well-defined homopolymers (PnBVE) and co/terpolymers [PnBVE-b-PCEVE-b-PSiDEGVE (ABC type) and PSiDEGVE-b-PnBVE-b-PSiDEGVE (CAC type)] by sequential living cationic polymerization of n-butyl vinyl ether (nBVE), 2-chloroethyl vinyl ether (CEVE) and tert-butyldimethylsilyl ethylene glycol vinyl ether (SiDEGVE), using mono-functional {[n-butoxyethyl acetate (nBEA)], [1-(2-chloroethoxy) ethyl acetate (CEEA)], [1-(2-(2-(t-butyldimethylsilyloxy)ethoxy) ethoxy) ethyl acetate (SiDEGEA)]} or di-functional [1,4-cyclohexanedimethanol di(1-ethyl acetate) (cHMDEA), (VEMOA)] initiators. The living cationic polymerizations of those monomers were conducted in hexane at -20 0C using Et3Al2Cl3 (catalyst) in the presence of 1 M AcOEt base.[1] The PCEVE segments of the synthesized block terpolymers were then used to react with living macroanions (PS-DPE-Li; poly styrene diphenyl ethylene lithium) to afford graft polymers. The quantitative desilylation of PSiDEGVE segments by n-Bu4N+F- in THF at 0 °C led to graft co- and terpolymers in which the polyalcohol is the outer block. These co-/terpolymers were subsequently subjected to “grafting-from” reactions by atom transfer radical polymerization (ATRP) of styrene to afford more complex macromolecular architectures. The base assisted living cationic polymerization of vinyl ethers were also used to synthesize well-defined α-hydroxyl polyvinylether (PnBVE-OH). The resulting polymers were then modified into an ATRP macro-initiator for the synthesis of well-defined block copolymers (PnBVE-b-PS). Bifunctional PnBVE with terminal malonate groups was also synthesized and used as a precursor for more complex architectures such as H-shaped block copolymer by “grafting-from” or

  2. Plasma-chemical modification of the structure and properties of poly(ethylene terephthalate) track membranes

    International Nuclear Information System (INIS)

    Kravets, L I; Dmitriev, S N; Dinescu, G; Lazea, A; Sleptsov, V V; Elinson, V M

    2007-01-01

    A process of extraction of the low-molecular products of the synthesis from the poly(ethylene terephthalate) track membranes modified by plasma has been investigated. It is shown that the deposition of a thin polymeric hydrocarbon film by cyclohexane plasma on the membrane surface with preliminary treatment in a plasma of non-polymerizing gases, for example oxygen, allows one to produce membranes possessing a high productivity. Their advantages are much better hydrodynamic properties and a small amount of the low-molecular products of the synthesis extracted by organic solvents

  3. Deposition of polymer films in low pressure reactive plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Biederman, H.

    1981-12-11

    Sputtering and plasma polymerization have found wide application as deposition techniques and have been extensively studied. R.f. sputtering of plastics, in particular of polytetrafluoroethylene, are discussed in the first part of this paper. In the second part, the general concept of plasma polymerization is considered and some examples of applications of plasma-polymerized films are presented. Special attention is paid to fluorocarbon and fluorochlorocarbon films. It has been suggested that these films could be used in thin film capacitors or as passivating layers for integrated circuits. In the optical field some of these films have been used as convenient moisture-resistant, protective and antireflecting coatings. Their mechanical properties have also been examined with the intention of using them for reducing surface friction. More recently some metals have been incorporated into fluorocarbon films to obtain layers with novel properties. Experiments in which films were prepared by the plasma polymerization of certain Freons are described. Some electrical and optical properties of these films are presented. High dielectric losses were obtained in a metal/film/metal sandwich configuration and the possible influence of ambient atmospheric effects on these measurements is discussed.

  4. Morphological study of synthesized chlorinated polyethylene by inductive plasma

    International Nuclear Information System (INIS)

    Olayo, M.G.; Cruz, G.; Carapia, L.; Fernandez, G.; Morales, J.

    2004-01-01

    In this work a morphological study on the synthesis of Chlorinated polyethylene for plasma starting from Trichloroethylene in a polymerization process and ablation simultaneous of metals, where silver atoms and copper are inserted directly during the growth of the polymer from the gas phase to the one solid is presented. (Author)

  5. Comparative studies of chemically synthesized and RF plasma ...

    Indian Academy of Sciences (India)

    journal of. April 2015 physics pp. 653–665. Comparative studies of ... MS received 16 April 2013; revised 5 February 2014; accepted 28 May 2014 ... RF plasma polymerization; poly(o-toluidine); Fourier transform infrared; UV–visible ... tial applications, e.g., as electrodes and membranes for electrochemical energy ...

  6. Hyperbranched polymers from polymerization in solid state

    International Nuclear Information System (INIS)

    Tomaz, Vivian A.; Silva, Rafael; Muniz, Edvani C.; Rubira, Adley F.

    2009-01-01

    The macroscopic properties of polymers are directly related to the chemical characteristics of the monomeric units and also with the geometric arrangement of polymer chains. Thus, polymers were synthesized from two well-known chelators EDTA and EDA. We evaluated the conditions for the polymerization of the precursors in the solid state. The polymerization was carried out varying the proportions of reagents, aiming the polymers with different degrees of chain branching and the materials were characterized by FTIR. The materials obtained from the best condition for synthesis were purified by size-exclusion chromatography of and were subjected to characterization by FTIR and NMR of 1 H and 13 C. The content of end groups in these samples was determined by back titration. (author)

  7. Light-harvesting organic photoinitiators of polymerization.

    Science.gov (United States)

    Lalevée, Jacques; Tehfe, Mohamad-Ali; Dumur, Frédéric; Gigmes, Didier; Graff, Bernadette; Morlet-Savary, Fabrice; Fouassier, Jean-Pierre

    2013-02-12

    Two new photoinitiators with unprecedented light absorption properties are proposed on the basis of a suitable truxene skeleton where several UV photoinitiators PI units such as benzophenone and thioxanthone are introduced at the periphery and whose molecular orbitals MO can be coupled with those of the PI units: a red-shifted absorption and a strong increase of the molecular extinction coefficients (by a ≈ 20-1000 fold factor) are found. These compounds are highly efficient light-harvesting photoinitiators. The scope and practicality of these photoinitiators of polymerization can be dramatically expanded, that is, both radical and cationic polymerization processes are accessible upon very soft irradiation conditions (halogen lamp, LED…︁) thanks to the unique light absorption properties of the new proposed structures. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Studies on radiation-induced graft polymerization

    International Nuclear Information System (INIS)

    Omichi, Hideki

    1978-09-01

    Radiation-induced graft polymerization is used extensively to improve physical properties of polymers, but few processes are now commercialized. The reason for this is partly inadequate basic research on the reaction and partly the difficulty in developing the grafting process with large radiation source. Firstly, new techniques are proposed of studying kinetics of the graft polymerization in heterogeneous system. Based on the grafting yield, the molecular weight of graft chains, and the amount of radicals given by ESR and activation analysis, kinetic parameters are obtained and the reaction mechanism of grafting process is discussed. Secondly, the development of grafting process of poly (vinyl chloride)-butadiene is described. By study of the reaction, process design, construction and operation of the pilot plant, and economic analysis of the process, this process with 60 Co gamma ray sources is shown to be industrially promising. (author)

  9. Radiation-induced emulsion polymerization of tetrafluoroethylene

    International Nuclear Information System (INIS)

    Suwa, Takeshi

    1979-10-01

    The radiation-induced emulsifier-free emulsion polymerization of tetrafluoroethylene (TFE) has been studied at initial pressure 2 - 25 kg/cm 2 and temperature 30 0 - 110 0 C for dose rate 0.57 x 10 4 - 3.0 x 10 4 rad/hr. Polytetrafluoroethylene (PTFE), a hydrophobic polymer, forms as a stable latex in the absence of an emulsifier. Stability of the latex is governed by the dose rate/TFE pressure ratio; it increases with sufficient TFE monomer. PTFE particles produced in this polymerization system are stable due to the carboxyl end groups and adsorption of OH - and HF on the particles. PTFE latex of molecular weight higher than 2 x 10 7 is obtained by addition of a radical scavenger such as hydroquinone. The molecular weight of PTFE can be measured from the heat of crystallization conveniently with high reliability, which was found in the course of study on the melting and crystallization behavior. (author)

  10. Inflation and Instability of a Polymeric Membrane

    DEFF Research Database (Denmark)

    Hassager, Ole; Kristensen, Susanne Brogaard; Larsen, Johannes Ruben

    1999-01-01

    We consider an axisymmetric polymeric membrane inflated by a uniform pressure difference acting across the membrane. The polymeric material is described by an arbitrary combination of a viscoelastic and a purely viscous component to the stress. Some viscoelastic materials described by a Mooney......-Rivlin model show a monotone increasing pressure during inflation of a spherical membrane. These materials develop a homogeneous membrane thickness in agreement with the Considere-Pearson condition. Molecularly based models such as the neo-Hookean, Doi-Edwards or Tom-Pom model show a pressure maximum when...... inflated. Membranes described by these models develop a local thinning of the membrane which may lead to bursting in finite time. (C) 1999 Elsevier Science B.V. All rights reserved....

  11. Radiation polymerization of tetrafluoroethylene in freon-22

    International Nuclear Information System (INIS)

    Schnautz, N.G.; Thompson, J.C.

    1979-02-01

    The radiation-induced solution-polymerization of tetrafluoroethylene in Freon-22 has been investigated over a temperature range of - 62 degrees celcius to 0 degrees celcius. The rate of polymerization for the in-source process was found to be directly propertional to monomer concentration and an activation energy of only 7,66 kj/mole was calculated. The number-average molecular mass of the product PTFE ranged from 2X10 4 to 6X10 4 and was relatively independent of the usual reaction parameters. The rate of postpolymerization was also found to be directly proportional to monomer concentration. The postpolyerization process did not result in any enchancement of the initial PTFE molecular mass [af

  12. Self-folding micropatterned polymeric containers.

    Science.gov (United States)

    Azam, Anum; Laflin, Kate E; Jamal, Mustapha; Fernandes, Rohan; Gracias, David H

    2011-02-01

    We demonstrate self-folding of precisely patterned, optically transparent, all-polymeric containers and describe their utility in mammalian cell and microorganism encapsulation and culture. The polyhedral containers, with SU-8 faces and biodegradable polycaprolactone (PCL) hinges, spontaneously assembled on heating. Self-folding was driven by a minimization of surface area of the liquefying PCL hinges within lithographically patterned two-dimensional (2D) templates. The strategy allowed for the fabrication of containers with variable polyhedral shapes, sizes and precisely defined porosities in all three dimensions. We provide proof-of-concept for the use of these polymeric containers as encapsulants for beads, chemicals, mammalian cells and bacteria. We also compare accelerated hinge degradation rates in alkaline solutions of varying pH. These optically transparent containers resemble three-dimensional (3D) micro-Petri dishes and can be utilized to sustain, monitor and deliver living biological components.

  13. Polymeric membrane studied using slow positron beam

    International Nuclear Information System (INIS)

    Hung, W.-S.; Lo, C.-H.; Cheng, M.-L.; Chen Hongmin; Liu Guang; Chakka, Lakshmi; Nanda, D.; Tung, K.-L.; Huang, S.-H.; Lee, Kueir-Rarn; Lai, J.-Y.; Sun Yiming; Yu Changcheng; Zhang Renwu; Jean, Y.C.

    2008-01-01

    A radioisotope slow positron beam has been built at the Chung Yuan Christian University in Taiwan for the research and development in membrane science and technology. Doppler broadening energy spectra and positron annihilation lifetime have been measured as a function of positron energy up to 30 keV in a polyamide membrane prepared by the interfacial polymerization between triethylenetetraamine (TETA) and trimesoyl chloride (TMC) on modified porous polyacrylonitrile (PAN) asymmetric membrane. The multilayer structures and free-volume depth profile for this asymmetric membrane system are obtained. Positron annihilation spectroscopy coupled with a slow beam could provide new information about size selectivity of transporting molecules and guidance for molecular designs in polymeric membranes

  14. Radiation-induced polymerization of hydrogen cyanide

    International Nuclear Information System (INIS)

    Mozhaev, P.S.; Kichigina, G.A.; Kiryukhin, D.P.

    1995-01-01

    The chain reaction of HCN polymerization in a γ-radiation field does not occur at 77 K. When irradiated HCN is warmed up to ambient temperature, a polymer is formed. The heat of polymerization of HCN is 44.0±6.0 kJ/mol and the polymer yield reaches 2.5% for a dose of 725 kGy. Amorphous polymer products (with yields increasing up to 33.5%) and needle crystals (presumably HCN tetramer) are formed upon storage of irradiated HCN at room temperature. The polymer is stable below 700 K, has a conductivity of 3x10 -5 Ω -1 cm -f1 , and displays an EPR spectrum typical of polyconjugated systems. A radical mechanism of the formation of conjugated chain -C=N-C=N- is suggested. The tetramer is produced by a combination of aminocyanocarbene biradicals

  15. RAFT polymerization and some of its applications.

    Science.gov (United States)

    Moad, Graeme; Rizzardo, Ezio; Thang, San H

    2013-08-01

    Reversible addition-fragmentation chain transfer (RAFT) is one of the most robust and versatile methods for controlling radical polymerization. With appropriate selection of the RAFT agent for the monomers and reaction conditions, it is applicable to the majority of monomers subject to radical polymerization. The process can be used in the synthesis of well-defined homo-, gradient, diblock, triblock, and star polymers and more complex architectures, which include microgels and polymer brushes. In this Focus Review we describe how the development of RAFT and RAFT application has been facilitated by the adoption of continuous flow techniques using tubular reactors and through the use of high-throughput methodology. Applications described include the use of RAFT in the preparation of polymers for optoelectronics, block copolymer therapeutics, and star polymer rheology control agents. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Forming of Polymeric Tubular Micro-components

    DEFF Research Database (Denmark)

    Qin, Yi; Zhao, Jie; Anyasodor, Gerald

    2015-01-01

    platform for the production of functional polymeric tubular micro-components. The chapter gives background on the current market and process development trends, followed by description of materials, process configuration, tool design and machine development for each processing technology as well......This chapter is intended to provide an overview of three nontraditional shaping technologies for the forming of polymeric micro-tubes, which are hot embossing, blow molding, and cross rolling, as well as realization of a process chain and the integration of a modular machine-based manufacturing...... as strategy for integration of the technologies and equipment into a common platform. Finally, potential applications of the technologies and facilities developed are highlighted....

  17. Polyisoprene Nanoparticles Prepared by Polymerization in Microemulsion

    Directory of Open Access Journals (Sweden)

    Y. Apolinar

    2010-01-01

    Full Text Available Batch polymerization of isoprene was carried out at 25∘C in a normal microemulsion stabilized with sodium dodecyl sulfate and initiated with the redox couple tert-butyl hydroperoxide/tetraethylene-pentamine. Characterization by transmission electronic microscopy showed that polyisoprene nanoparticles with number-average diameter close to 20 nm were obtained. The low molecular weights obtained, as determined by gel permeation chromatography, were probably due to chain scission as inferred from the oxidative ambient at which polymerization was carried out. Microstructure calculated from infrared spectroscopy data indicates that the obtained polyisoprene contains around 80% total 1,4 units, which is in accordance with its glass transition temperature (-60.8∘C determined by differential scanning calorimetry.

  18. Pharmaceutical Applications of Polymeric Nano materials

    International Nuclear Information System (INIS)

    Wu, L.; Sun, L.

    2011-01-01

    With significant attention focused on nano science and nano technology in recent years, nano materials have been used in a wide variety of applications such as automotive, environmental, energy, catalysis, biomedical, drug delivery, and polymeric industries. Among those fields, the application of nano materials with pharmaceutical science is an emerging and rapidly growing field and has drawn increasing attention recently. Research and development in this field is mainly focused on several aspects such as the discoveries of novel functional nano materials, exploration on nanoparticles with controlled and targeted drug delivery characteristics, and investigation of bio functionalized and diagnostic nano materials. In this special issue, we have invited a few papers related to recent advances in pharmaceutical application of polymeric nano materials

  19. Dusty plasmas

    International Nuclear Information System (INIS)

    Jones, M.E.; Winske, D.; Keinigs, R.; Lemons, D.

    1996-01-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project has been to develop a fundamental understanding of dusty plasmas at the Laboratory. While dusty plasmas are found in space in galactic clouds, planetary rings, and cometary tails, and as contaminants in plasma enhanced fabrication of microelectronics, many of their properties are only partially understood. Our work has involved both theoretical analysis and self-consistent plasma simulations to understand basic properties of dusty plasmas related to equilibrium, stability, and transport. Such an understanding can improve the control and elimination of plasma dust in industrial applications and may be important in the study of planetary rings and comet dust tails. We have applied our techniques to the study of charging, dynamics, and coagulation of contaminants in plasma processing reactors for industrial etching and deposition processes and to instabilities in planetary rings and other space plasma environments. The work performed in this project has application to plasma kinetics, transport, and other classical elementary processes in plasmas as well as to plasma waves, oscillations, and instabilities

  20. Plasma chromatography

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    This book examines the fundamental theory and various applications of ion mobility spectroscopy. Plasma chromatography developed from research on the diffusion and mobility of ions. Topics considered include instrument design and description (e.g., performance, spectral interpretation, sample handling, mass spectrometry), the role of ion mobility in plasma chromatography (e.g., kinetic theory of ion transport), atmospheric pressure ionization (e.g., rate equations), the characterization of isomers by plasma chromatography (e.g., molecular ion characteristics, polynuclear aromatics), plasma chromatography as a gas chromatographic detection method (e.g., qualitative analysis, continuous mobility monitoring, quantitative analysis), the analysis of toxic vapors by plasma chromatography (e.g., plasma chromatograph calibration, instrument control and data processing), the analysis of semiconductor devices and microelectronic packages by plasma chromatography/mass spectroscopy (e.g., analysis of organic surface contaminants, analysis of water in sealed electronic packages), and instrument design and automation (hardware, software)

  1. EDOT polymerization at photolithographically patterned functionalized graphene

    Czech Academy of Sciences Publication Activity Database

    Kovaříček, Petr; Drogowska, Karolina; Melníková Komínková, Zuzana; Blechta, Václav; Bastl, Zdeněk; Gromadzki, Daniel; Fridrichová, Michaela; Kalbáč, Martin

    2017-01-01

    Roč. 113, MAR 2017 (2017), s. 33-39 ISSN 0008-6223 R&D Projects: GA MŠk LL1301; GA MŠk(CZ) LM2015073 Grant - others:AVČR PPPLZ(CZ) L200401551 Institutional support: RVO:61388955 Keywords : polymerization * electrochemical doping * graphene Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 6.337, year: 2016

  2. Emulsion polymerization with high energy radiation

    International Nuclear Information System (INIS)

    Stannett, V.T.; Stahel, E.P.

    1992-01-01

    High energy radiation, particularly that of cobalt-60 or caesium-137 gamma-rays, provides in principle an ideal initiator for emulsion polymerization. The high free radical yields from the radiolysis of the aqueous phase combined with the high kinetic chain lengths associated with emulsion polymerization lead to a highly effective utilization of the radiation. There are other important advantages compared with the use of chemical initiators such as potassium persulfate. These are outlined in the chapter, together with some attendant disadvantages. Radiation-induced initiation is temperature independent, and low temperature polymerizations can be conducted with ease. Monomers that mainly terminate their growing chains by chain transfer to monomer give higher molecular weights at lower temperatures. Industrially, vinyl acetate is an important example of such a monomer, and it has been studied using radiation initiation. Both laboratory and pilot plant studies have been carried out and reported. The results are summarized in this chapter. Styrene is the classical example of a material that under a number of conditions closely obeys the so-called ideal Smith-Ewart kinetics. It has been found that under similar conditions but substituting radiation for potassium persulfate as the initiator, ideal kinetics were closely followed. Most of the conventional and some non-standard vinyl and diene monomers have been studied to some extent with radiation-initiated polymerizations in emulsion. To conserve space however, this chapter presents and discusses the results obtained only with styrene and vinyl acetate, both in laboratory and pilot plant investigations. Other monomers and special situations are referenced either directly or to the other available reviews. (orig.)

  3. Personal Cooling Fabric Based on Polymeric Thermoelectrics

    Science.gov (United States)

    2016-07-28

    There are also concerns about environmental impact given their toxic heavy metal content. Despite these limitations and the lack of improvement in...polymeric TE materials were studied, they offered the additional advantages (over metallic materials) of low density, no toxic heavy metals (bismuth, lead...First, fluorene was reacted with two equivalents of bromoethane under basic conditions to afford 9,9’-diethyl fluorine , which was bromomethylated

  4. High-voltage polymeric insulated cables

    Energy Technology Data Exchange (ETDEWEB)

    Ross, A

    1987-01-01

    Reviews developments in high-voltage (here defined as 25 kV, 66 kV and 132 kV) polymeric insulated cables in the UK over the period 1979-1986, with particular reference to the experience of the Eastern Electricity Board. Outlines the background to the adoption of XPLE-insulated solid cable, and the design, testing, terminations, jointing and costs of 25 kV, 66 kV and 132 kV cables.

  5. Adaptive polymeric system for Hebbian type learning

    OpenAIRE

    2011-01-01

    Abstract We present the experimental realization of an adaptive polymeric system displaying a ?learning behaviour?. The system consists on a statistically organized networks of memristive elements (memory-resitors) based on polyaniline. In a such network the path followed by the current increments its conductivity, a property which makes the system able to mimic Hebbian type learning and have application in hardware neural networks. After discussing the working principle of ...

  6. Texturation and superhydrophobicity of polyethylene terephthalate thanks to plasma technology

    International Nuclear Information System (INIS)

    Tarrade, Jeanne; Darmanin, Thierry; Taffin de Givenchy, Elisabeth; Guittard, Frédéric; Debarnot, Dominique

    2014-01-01

    Anti-bioadhesive surfaces were designed from polyethylene terephthalate (PET) by three steps plasma-treatment. First, the nano-pattern is created by oxygen plasma-treatment with controlled dimensions. Then, the plasma-treated polymeric surface was hydrophobized with a tetrafluorocarbon plasma, allowing to obtain a water contact angle of 145 ± 4°. However, the SEM pictures give evidence to show the degradation of the structuration caused by the CF 4 -plasma and consequently, the superhydrophobicity was not reached. Thus, a plasma-polypyrrole layer was deposited before the plasma-fluorination, which has a protective role against the degradation generated by fluorinated species, preserving the structuration and improving the fluorination rate. Therefore, the obtained surfaces are superhydrophobic with water contact angle of 157 ± 2° and a hysteresis of 65 ± 3°. The ability of these surfaces to reduce bioadhesion will be performed in further work.

  7. Morphological study of synthesized chlorinated polyethylene by inductive plasma; Estudio morfologico de polietileno clorado sintetizado por plasmas inductivos

    Energy Technology Data Exchange (ETDEWEB)

    Olayo, M.G.; Cruz, G.; Carapia, L.; Fernandez, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Morales, J. [UAM-I, A.P. 55-534, Mexico D.F. (Mexico)

    2004-07-01

    In this work a morphological study on the synthesis of Chlorinated polyethylene for plasma starting from Trichloroethylene in a polymerization process and ablation simultaneous of metals, where silver atoms and copper are inserted directly during the growth of the polymer from the gas phase to the one solid is presented. (Author)

  8. Allylthioketone Mediated Free Radical Polymerization of Methacrylates

    Directory of Open Access Journals (Sweden)

    Feng Zhong

    2017-11-01

    Full Text Available By combination of high trapping free radical efficiency of the thioketone and resonance of the allylic radical, a new type of mediating agent, 1,3,3-triphenylprop-2-ene-1-thione (TPPT has been successfully synthesized, and then is used to study controlled free radical polymerization of methacrylates. Very stable TPPT radicals at the end of poly(methyl methacrylate (PMMA are detected in the polymerization of MMA using TPPT and AIBN as the control agent and initiator. The MALDI-TOF MS spectra are used to identify terminal groups of the resultant poly(glycidyl methacrylate (PGMA, and major component of the obtained polymer has the structure, (CH32(CNC-PGMA-C7H9O3. Chain extension reaction tests ascertain formation of the dead polymers during the polymer storage and purification process of the polymers. Owing to very slow fragmentation reaction of the TPPT-terminated polymethacrylate radical and addition reaction of this radical with a primary radical, the growing chain radicals are difficult to be regenerated, leading to an unobvious change of the molecular weight with monomer conversion. The molecular weights of polymers can be controlled by the ratios of monomer/initiator and TPPT/initiator. However, the first order kinetics of the polymerization and the polymers with narrow polydispersity are obtained, and these phenomena are discussed. This study provides useful information on how to design a better controlling agent.

  9. Comparison of potentials for polymeric liquids

    International Nuclear Information System (INIS)

    Jung, Hae Young

    2002-01-01

    Many theories for polymeric liquids are based on the concepts of cell, hole, free volume of lattice etc. In this theories, van der Waals potential, Lennard-Jones 6-12 potential and their modified potentials are commonly used. In this work, Mie(p,6)potential was applied to the Continuous Lattice Fluid Theory (which extends the discrete lattices of Lattice Fluid Theory to classically continuous lattices) and Dee-Walsch's Cell Theory (which modifies Flory's Equation of State Theory). Both of them are known to be successful theories for polymeric liquids. Thus, PVT values changing with p (the exponent in the repulsion potential) were calculated and compared with experimental values. And, calculated values of Lattice Fluid theory, Flory's Equation of State Theory and Cho-Sanchez Theory using perturbation method were also compared. Through the calculated results, van der Waals potential, Lennard-Jones 6-12 potential and Mie(p,6) potential for polymeric liquids were compared with each other

  10. Polymerization initated at sidewalls of carbon nanotubes

    Science.gov (United States)

    Tour, James M. (Inventor); Hudson, Jared L. (Inventor); Krishnamoorti, Ramanan (Inventor); Yurekli, Koray (Inventor); Mitchell, Cynthia A. (Inventor)

    2011-01-01

    The present invention is directed to aryl halide (such as aryl bromide) functionalized carbon nanotubes that can be utilized in anionic polymerization processes to form polymer-carbon nanotube materials with improved dispersion ability in polymer matrices. In this process the aryl halide is reacted with an alkyllithium species or is reacted with a metal to replace the aryl-bromine bond with an aryl-lithium or aryl-metal bond, respectively. It has further been discovered that other functionalized carbon nanotubes, after deprotonation with a deprotonation agent, can similarly be utilized in anionic polymerization processes to form polymer-carbon nanotube materials. Additionally or alternatively, a ring opening polymerization process can be performed. The resultant materials can be used by themselves due to their enhanced strength and reinforcement ability when compared to their unbound polymer analogs. Additionally, these materials can also be blended with pre-formed polymers to establish compatibility and enhanced dispersion of nanotubes in otherwise hard to disperse matrices resulting in significantly improved material properties. The resultant polymer-carbon nanotube materials can also be used in drug delivery processes due to their improved dispersion ability and biodegradability, and can also be used for scaffolding to promote cellular growth of tissue.

  11. Application of atmospheric pressure plasma on polyethylene for increased prosthesis adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Van Vrekhem, S., E-mail: stijn.vanvrekhem@ugent.be [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering and Architecture, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Ghent (Belgium); Cools, P. [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering and Architecture, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Ghent (Belgium); Declercq, H. [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering and Architecture, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Ghent (Belgium); Tissue Engineering Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185 6B3, 9000 Ghent (Belgium); Van Tongel, A. [Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185 13K12, 9000 Ghent (Belgium); Vercruysse, C.; Cornelissen, M. [Tissue Engineering Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185 6B3, 9000 Ghent (Belgium); De Geyter, N.; Morent, R. [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering and Architecture, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Ghent (Belgium)

    2015-12-01

    Biopolymers are often subjected to surface modification in order to improve their surface characteristics. The goal of this study is to show the use of plasma technology to enhance the adhesion of ultra-high molecular weight polyethylene (UHMWPE) shoulder prostheses. Two different plasma techniques (low pressure plasma activation and atmospheric pressure plasma polymerization) are performed on UHMWPE to increase the adhesion between (1) the polymer and polymethylmethacrylate (PMMA) bone cement and (2) the polymer and osteoblast cells. Both techniques are performed using a dielectric barrier discharge (DBD). A previous paper showed that low pressure plasma activation of UHMWPE results in the incorporation of oxygen-containing functional groups, which leads to an increased surface wettability. Atmospheric pressure plasma polymerization of methylmethacrylate (MMA) on UHMWPE results in a PMMA-like coating, which could be deposited with a high degree of control of chemical composition and layer thickness. The thin film also proved to be relatively stable upon incubation in a phosphate buffer solution (PBS). This paper discusses the next stage of the study, which includes testing the adhesion of the plasma-activated and plasma-polymerized samples to bone cement through pull-out tests and testing the cell adhesion and proliferation on the samples. In order to perform the pull-out tests, all samples were cut to standard dimensions and fixed in bone cement in a reproducible way with a sample holder specially designed for this purpose. The cell adhesion and proliferation were tested by means of an MTS assay and live/dead staining after culturing MC3T3 osteoblast cells on UHMWPE samples. The results show that both plasma activation and plasma polymerization significantly improve the adhesion to bone cement and enhance cell adhesion and proliferation. In conclusion, it can be stated that the use of plasma technology can lead to an implant with improved quality and a subsequent

  12. KINETICS OF SUSPENDED EMULSION POLYMERIZATION OF METHYL METHACRYLATE

    Institute of Scientific and Technical Information of China (English)

    Yong-zhong Bao; Cheng-xi Wang; Zhi-ming Huang; Zhi-xue Weng

    2004-01-01

    The kinetics of suspended emulsion polymerization of methyl methacrylate (MMA), in which water acted as the dispersed phase and the mixture of MMA and cyclohexane as the continuous phase, was investigated. It showed that the initial polymerization rate (Rp0) and steady-state polymerization rate (Rp) were proportional to the mass ratio between water and oil phase, and increased as the polymerization temperature, the potassium persulphate concentration ([I]) and the Tween20 emulsifier concentration ([S]) increased. The relationships between the polymerization rate and [I] and [S] were obtained as follows: Rp0 ∝ [I]0.73[S]0.32 and Rp ∝ [I]0.71[S]0.23. The above exponents were close to those obtained from normal MMA emulsion polymerization. It also showed that the average molecular weight of the resulting poly(methyl methacrylate) decreased as the polymerization temperature, [I] and [S] increased. Thus, MMA suspended emulsion polymerization could be considered as a combination of many miniature emulsion polymerizations proceeding in water drops and obeyed the classical kinetics of MMA emulsion polymerization.

  13. Neutral Polymeric Micelles for RNA Delivery

    Science.gov (United States)

    Lundy, Brittany B.; Convertine, Anthony; Miteva, Martina; Stayton, Patrick S.

    2013-01-01

    RNA interference (RNAi) drugs have significant therapeutic potential but delivery systems with appropriate efficacy and toxicity profiles are still needed. Here, we describe a neutral, ampholytic polymeric delivery system based on conjugatable diblock polymer micelles. The diblock copolymer contains a hydrophilic poly[N-(2-hydroxypropyl) methacrylamide-co-N-(2-(pyridin-2- yldisulfanyl)ethyl)methacrylamide) (poly[HPMA-co-PDSMA]) segment to promote aqueous stability and facilitate thiol-disulfide exchange reactions, and a second ampholytic block composed of propyl acrylic acid (PAA), dimethylaminoethyl methacrylate (DMAEMA), and butyl methacrylate (BMA). The poly[(HPMA-co-PDSMA)-b-(PAA-co-DMAEMA-co-BMA)] was synthesized using Reversible Addition-Fragmentation chain Transfer (RAFT) polymerization with an overall molecular weight of 22,000 g/mol and a PDI of 1.88. Dynamic light scattering and fluorescence measurements indicated that the diblock copolymers self-assemble under aqueous conditions to form polymeric micelles with a hydrodynamic radius and critical micelle concentration of 25 nm and 25 μg/mL respectively. Red blood cell hemolysis experiments show that the neutral hydrophilic micelles have potent membrane destabilizing activity at endosomal pH values. Thiolated siRNA targeting glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was directly conjugated to the polymeric micelles via thiol exchange reactions with the pyridal disulfide groups present in the micelle corona. Maximum silencing activity in HeLa cells was observed at a 1:10 molar ratio of siRNA to polymer following a 48 h incubation period. Under these conditions 90 % mRNA knockdown and 65 % and protein knockdown of at 48 h was achieved with negligible toxicity. In contrast the polymeric micelles lacking a pH-responsive endosomalytic segment demonstrated negligible mRNA and protein knockdown under these conditions. The potent mRNA knockdown and excellent biocompatibility of the neutral siRNA conjugates

  14. Enhanced opsonisation of Rhesus D-positive human red blood cells by recombinant polymeric immunoglobulin G anti-G antibodies.

    Science.gov (United States)

    Díaz-Solano, Dylana; Fuenmayor, Jaheli; Montaño, Ramon F

    2018-02-01

    Anti-RhD antibodies (anti-D) are important in the prophylaxis of haemolytic disease of the foetus and newborn (HDFN) due to RhD incompatibility. Current preparations of anti-D are sourced from hyperimmune human plasma, so its production carries a risk of disease and is dependent on donor availability. Despite the efforts to develop a monoclonal preparation with similar prophylactic properties to the plasma-derived anti-D, no such antibody is yet available. Here we studied the agglutinating, opsonic and haemolytic activities of two recombinant polymeric immunoglobulins (Ig) against the G antigen of the Rh complex. Recombinant polymeric anti-G IgG1 (IgG1μtp) and IgG3 (IgG3μtp) were produced in vitro, purified by protein G-affinity chromatography, and analysed by gel electrophoresis. Their agglutinating, opsonic and haemolytic activities were evaluated using haemagglutination, erythrophagocytosis, and complement activation assays. The recombinant IgG1μtp and IgG3μtp anti-G antibodies ranged from 150,000 to 1,000,000 Da in molecular weight, indicating the formation of polymeric IgG. No complement activation or haemolytic activity was detected upon incubation of RhD-positive red-blood cells with the polymeric anti-G IgG. Both polymers were better opsonins than a prophylactic preparation of plasma-derived anti-D. The enhanced opsonic properties of the polymeric anti-G IgG1μtp and IgG3μtp could allow them to mediate the clearance of RhD-positive red blood cells from circulation more efficiently than natural or other synthetic prophylactic anti-D options. Their inability to induce complement-mediated haemolysis would be prophylactically convenient and is comparable in vitro to that of the available plasma-derived polyclonal anti-D preparations. The described properties suggest that polymeric antibodies like these (but with anti-D specificity) may be testable candidates for prophylaxis of HDFN caused by anti-D.

  15. Biodegradable Polyelectrolyte Obtained by Radiation Polymerization

    International Nuclear Information System (INIS)

    Craciun, G.; Martin, D.; Manaila, E.; Nemtanu, M.; Brasoveanu, M.; Ighigeanu, D.

    2009-01-01

    Poly electrolytes are water-soluble polymers carrying ionic charge along the polymer chain. Depending upon the charge, these polymers are anionic or cationic. The inherent solid - liquid separating efficiency makes these poly electrolytes a unique class of polymers which find extensive application in potable water, industrial raw and process water, municipal sewage treatment, mineral processing and metallurgy, oil drilling and recovery, etc. Also, due to their ability to produce advanced induced coagulation, a considerable amount of bacteria and viruses are precipitated together with the suspended solids. Especially the acrylamide polymers are very efficacious for water treatment but acrylamide is a toxic monomer and therefore their use are governed by international standards that provide the residual acrylamide monomer content (RAMC) in them be less than 0.05%. Under these circumstances our attention was focused on the following research steps that are presented in this paper: 1) Preparation of a special class of poly electrolytes, named Pn, with very low RAMC values, based on electron beam (EB), microwave (MW) and EB + MW induced co-polymerization of aqueous solutions containing appropriate mixtures of acrylamide (AMD) and acrylic acid (AA) monomers (AMD - AA co-polymers). The Pn were obtained by radiation technology with very small RAMC (under 0.01%) as well as in a wide range of molecular weights and charge densities. Very low AMD monomer content of Pn is due to the major advantages of radiation induced polymerization in aqueous solution containing monomers. Due to water presence in the EB irradiated system, irradiated water radicals facilitate the polymerization process and increase rate and level of monomers conversion in co-polymers. Also, once again, by the presence of water, which absorbs MW energy very strongly, the MW polymerization reaction rate is much enhanced resulting in a reaction time about 50-100 times lowers than by conventional heating. Also

  16. Polymeric micellar pH-sensitive drug delivery system for doxorubicin.

    Science.gov (United States)

    Hrubý, Martin; Konák, Cestmír; Ulbrich, Karel

    2005-03-02

    A novel polymeric micellar pH-sensitive system for delivery of doxorubicin (DOX) is described. Polymeric micelles were prepared by self-assembly of amphiphilic diblock copolymers in aqueous solutions. The copolymers consist of a biocompatible hydrophilic poly(ethylene oxide) (PEO) block and a hydrophobic block containing covalently bound anthracycline antibiotic DOX. The starting block copolymers poly(ethylene oxide)-block-poly(allyl glycidyl ether) (PEO-PAGE) with a very narrow molecular weight distribution (Mw/Mn ca. 1.05) were prepared by anionic ring opening polymerization using sodium salt of poly(ethylene oxide) monomethyl ether as macroinitiator and allyl glycidyl ether as functional monomer. The copolymers were covalently modified via reactive double bonds by the addition of methyl sulfanylacetate. The resulting ester subsequently reacted with hydrazine hydrate yielding polymer hydrazide. The hydrazide was coupled with DOX yielding pH-sensitive hydrazone bonds between the drug and carrier. The resulting conjugate containing ca. 3 wt.% DOX forms micelles with Rh(a)=104 nm in phosphate-buffered saline. After incubation in buffers at 37 degrees C DOX was released faster at pH 5.0 (close to pH in endosomes; 43% DOX released within 24 h) than at pH 7.4 (pH of blood plasma; 16% DOX released within 24 h). Cleavage of hydrazone bonds between DOX and carrier continues even after plateau in the DOX release from micelles incubated in aqueous solutions is reached.

  17. Bio-inspired polymeric patterns with enhanced wear durability for microsystem applications

    International Nuclear Information System (INIS)

    Singh, R. Arvind; Siyuan, L.; Satyanarayana, N.; Kustandi, T.S.; Sinha, Sujeet K.

    2011-01-01

    At micro/nano-scale, friction force dominates at the interface between bodies moving in relative motion and severely affects their smooth operation. This effect limits the performance of microsystem devices such as micro-electro-mechanical systems (MEMS). In addition, friction force also leads to material removal or wear and thereby reduces the durability i.e. the useful operating life of the devices. In this work, we fabricated bio-inspired polymeric patterns for tribological applications. Inspired by the surface features on lotus leaves namely, the protuberances and wax, SU-8 polymeric films spin-coated on silicon wafers were topographically and chemically modified. For topographical modification, micro-scale patterns were fabricated using nanoimprint lithography and for chemical modification, the micro-patterns were coated with perfluoropolyether nanolubricant. Tribological investigation of the bio-inspired patterns revealed that the friction coefficients reduced significantly and the wear durability increased by several orders. In order to enhance the wear durability much further, the micro-patterns were exposed to argon/oxygen plasma and were subsequently coated with the perfluoropolyether nanolubricant. Bio-inspired patterns with enhanced wear durability, such as the ones investigated in the current work, have potential tribological applications in MEMS/Bio-MEMS actuator-based devices. Highlights: →Bio-inspired polymeric patterns for tribological applications in microsystems. →Novel surface modification for the patterns to enhance tribological properties. →Patterns show low friction properties and extremely high wear durability.

  18. Enhanced surface functionality via plasma modification and plasma deposition techniques to create more biologically relevant materials

    Science.gov (United States)

    Shearer, Jeffrey C.

    Functionalizing nanoparticles and other unusually shaped substrates to create more biologically relevant materials has become central to a wide range of research programs. One of the primary challenges in this field is creating highly functionalized surfaces without modifying the underlying bulk material. Traditional wet chemistry techniques utilize thin film depositions to functionalize nanomaterials with oxygen and nitrogen containing functional groups, such as --OH and --NHx. These functional groups can serve to create surfaces that are amenable to cell adhesion or can act as reactive groups for further attachment of larger structures, such as macromolecules or antiviral agents. Additional layers, such as SiO2, are often added between the nanomaterial and the functionalized coating to act as a barrier films, adhesion layers, and to increase overall hydrophilicity. However, some wet chemistry techniques can damage the bulk material during processing. This dissertation examines the use of plasma processing as an alternative method for producing these highly functionalized surfaces on nanoparticles and polymeric scaffolds through the use of plasma modification and plasma enhanced chemical vapor deposition techniques. Specifically, this dissertation will focus on (1) plasma deposition of SiO2 barrier films on nanoparticle substrates; (2) surface functionalization of amine and alcohol groups through (a) plasma co-polymerization and (b) plasma modification; and (3) the design and construction of plasma hardware to facilitate plasma processing of nanoparticles and polymeric scaffolds. The body of work presented herein first examines the fabrication of composite nanoparticles by plasma processing. SiOxC y and hexylamine films were coated onto TiO2 nanoparticles to demonstrate enhanced water dispersion properties. Continuous wave and pulsed allyl alcohol plasmas were used to produce highly functionalized Fe2 O3 supported nanoparticles. Specifically, film composition was

  19. Measurement and Analysis of in vitro Actin Polymerization

    Science.gov (United States)

    Doolittle, Lynda K.; Rosen, Michael K.; Padrick, Shae B.

    2014-01-01

    Summary The polymerization of actin underlies force generation in numerous cellular processes. While actin polymerization can occur spontaneously, cells maintain control over this important process by preventing actin filament nucleation and then allowing stimulated polymerization and elongation by several regulated factors. Actin polymerization, regulated nucleation and controlled elongation activities can be reconstituted in vitro, and used to probe the signaling cascades cells use to control when and where actin polymerization occurs. Introducing a pyrene fluorophore allows detection of filament formation by an increase in pyrene fluorescence. This method has been used for many years and continues to be broadly used, owing to its simplicity and flexibility. Here we describe how to perform and analyze these in vitro actin polymerization assays, with an emphasis on extracting useful descriptive parameters from kinetic data. PMID:23868594

  20. Plasma physics

    CERN Document Server

    Drummond, James E

    1961-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  1. Plasma generator

    International Nuclear Information System (INIS)

    Omichi, Takeo; Yamanaka, Toshiyuki.

    1976-01-01

    Object: To recycle a coolant in a sealed hollow portion formed interiorly of a plasma limiter itself to thereby to cause direct contact between the coolant and the plasma limiter and increase of contact area therebetween to cool the plasma limiter. Structure: The heat resulting from plasma generated during operation and applied to the body of the plasma limiter is transmitted to the coolant, which recycles through an inlet and outlet pipe, an inlet and outlet nozzle and a hollow portion to hold the plasma limiter at a level less than a predetermined temperature. On the other hand, the heater wire is, at the time of emergency operation, energized to heat the plasma limiter, but this heat is transmitted to the limiter body to increase the temperature thereof. However, the coolant recycling the hollow portion comes into direct contact with the limiter body, and since the plasma limiter surround the hollow portion, the heat amount transmitted from the limiter body to the coolant increases to sufficiently cool the plasma limiter. (Yoshihara, H.)

  2. Controlled change of transport properties of poly(ethylene terephthalate) track membranes by plasma method

    International Nuclear Information System (INIS)

    Kravets, L I; Dmitriev, S N; Drachev, A I; Gilman, A B; Lazea, A; Dinescu, G

    2007-01-01

    A process of plasma polymerization of dimethylaniline and acrylic acid vapours on the surface of poly(ethylene terephthalate) track membranes has been investigated. The surface and hydrodynamic properties of the composite membranes produced in this case have been studied. It is shown that the water permeability of the obtained polymeric membranes can be controlled by changing the filtrate pH. Membranes with such properties can be used for controllable drug delivery and in sensor control

  3. Immobilization of β-galactosidase from Kluyveromyces lactis onto polymeric membrane surfaces: effect of surface characteristics.

    Science.gov (United States)

    Güleç, Hacı Ali

    2013-04-01

    The aim of this study was to investigate the effects of surface characteristics of plain and plasma modified cellulose acetate (CA) membranes on the immobilization yield of β-galactosidases from Kluyveromyces lactis (KLG) and its galacto-oligosaccharide (GOS) yield, respectively. Low pressure plasma treatments involving oxygen plasma activation, plasma polymerization (PlsP) of ethylenediamine (EDA) and PlsP of 2-mercaptoethanol were used to modify plain CA membrane surfaces. KLG enzyme was immobilized onto plain and oxygen plasma treated membrane surfaces by simple adsorption. Oxygen plasma activation increased the hydrophylicity of CA membrane surfaces and it improved the immobilization yield of the enzyme by 42%. KLG enzyme was also immobilized onto CA membrane surfaces through amino groups created by PlsP of EDA via covalent binding. Plasma action at 60W plasma power and 15 min. exposure time improved the amount of membrane bounded enzyme by 3.5-fold. The enrichment of the amount of amino groups via polyethyleneimine (PEI) addition enhanced this increase from 3.5-fold to 4.5-fold. Although high enzyme loading was achived (65-83%), both of the methods dramatically decreased the enzyme activity (11-12%) and GOS yield due to probably negative effects of active amino groups. KLG enzyme was more effectively immobilized onto thiolated CA membrane surface created by PlsP of 2-mercaptoethanol with high immobilization yield (70%) and especially high enzyme activity (46%). Immobilized enzymes on the CA membranes treated by PlsP were successively reutilized for 5-8 cycles at 25°C and enzymatic derivatives retained approximately 75-80% of their initial activites at the end of the reactions. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Polypropylene/graphite nanocomposites by in situ polymerization

    International Nuclear Information System (INIS)

    Milani, Marceo A.; Galland, Giselda B.; Quijada, Raul

    2011-01-01

    This work presents the synthesis of nanocomposites of polypropylene/graphite by in situ polymerization using metallocene catalyst and graphene nanosheets. Initially was analyzed which of the metallocene catalysts rac-Et(Ind) 2 ZrCl 2 or rac-Me 2 Si(Ind) 2 ZrCl 2 produces polypropylene with mechanical properties more relevant. Then it were performed the in situ polymerization reactions to obtain the nanocomposites. The polymeric materials were characterized by XRD, DSC, GPC and DMTA. (author)

  5. Characterization of a dielectric barrier plasma gun discharging at atmospheric pressure

    International Nuclear Information System (INIS)

    Zhang Guangqiu; Ge Yuanjing; Zhang Yuefei; Chen Guangliang

    2004-01-01

    The authors develop a plasma gun based on dielectric barrier discharge and working at atmospheric pressure. A theoretical model to predict the gun discharge voltage is built, which is in agreement with the experimental results. After investigating the characterization of discharging gun and utilizing it for polymerization, authors find that the gun can be used as a source to generate a stable uniform plasma for different plasma-processing technologies. (author)

  6. Modification of surface properties of LLDPE by water plasma discharge

    International Nuclear Information System (INIS)

    Chantara Thevy Ratnam; Hill, D.J.T.; Firas Rasoul; Whittaker, A.K.; Imelda Keen

    2007-01-01

    Linear low density polyethylene (LLDPE) surface was modified by water plasma treatment. The LLDPE surface was treated at 10 and 20 W discharge power at various exposure times. A laboratory scale Megatherm radio frequency (RF) plasma apparatus that operates at 27 MHz was used to generate the water plasmas. The changes in chemical structure of the LLDPE polymeric chain upon plasma treatment were characterized by FTIR and XPS techniques. The selectivity of trifluoroacetic anhydride (TFAA) toward hydroxyl groups is used to quantify the hydroxyl groups formed on the polymer surface upon plasma treatment. After exposition to the plasma discharge a decline in water contact angle were observed. FTIR and XPS measurements indicate an oxidation of degraded polymeric chains and creation of hydroxyl, carbonyl, ether, ester and carboxyl groups. Chemical derivatization with TFAA of water plasma treated polymer surfaces has shown that under the conditions employed, a very small (less than 5%) of the oxygen introduced by the water plasma treatment was present as hydroxyl group. (Author)

  7. Investigations in the field of solid state polymerization Pt. 38

    International Nuclear Information System (INIS)

    Hardy, Gy.; Cser, F.; Nyitrai, K.; Fedorova, N.

    1980-01-01

    The stuctural and radiation chemical data of vinyl monomers with long chain paraffinic or cholesteric side groups are critically reviewed. Based on their structural and polymerization kinetical characteristics the monomers may be classified into three groups. Oblique layers are favourable for homogeneous topotactic polymerization. This is characterized by a low activation energy and a radiochemical efficiency very similar to that measured in liquid state polymerization. The tilted layers are not favourable for homogeneous topotactic polymerization. Allyl monomers yield polymers with higher molecular weights in the layer structure than in liquid states. (author)

  8. Nanoporous Polymeric Grating-Based Optical Biosensors (Preprint)

    National Research Council Canada - National Science Library

    Hsiao, Vincent K; Waldeisen, John R; Lloyd, Pamela F; Bunning, Timothy J; Huang, Tony J

    2007-01-01

    .... The fabrication process of the nanoporous polymeric grating involves holographic interference patterning and a functionalized pre-polymer syrup that facilitates the immobilization of biomolecules...

  9. Biocompatible Polymeric Materials Intended for Drug Delivery and Therapeutic Applications

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Javakhishvili, Irakli; Bednarek, Melania

    2007-01-01

    of polymer blocks by “click chemistry”. An all polymerization strategy would imply preparing polymers by living/controlled techniques in such a manner that one block after polymerization can be converted to a macroinitiator enabling the second block to polymerize. The coupling strategy invariably inserts...... a linking unit, 1,4-triazol, resulting from the catalyzed, irreversible 1,3-dipolar cycloaddition reaction between an alkyne and an azide. Thus, this strategy necessitates the proper end functionalization of the polymeric building blocks. Fortunately the 1,4-triazol unit is FDA approved already existing...

  10. STUDIES ON VINYL POLYMERIZATION WITH INITIATION SYSTEM CONTAINING AMINE DERIVATIVES

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; ZHANG Jingyi; FENG Xinde(S. T. Voong)

    1983-01-01

    Two main types of amine-containing initiation systems were studied in this work. In the case of MMA polymerization initiated by BPO-amine (DMT, DHET, DMA) redox systems, it was found that the polymerization rate and colour stability of the polymer for different amine systems were in the following order: DMT≈DHET>DMA. Accordingly, BPO-DMT and BPO-DHET are effective initiators. In the case of MEMA polymerization by amine (DMT, DHET, DMA) alone, it was found that the polymerization rate and the percentage of conversion for these different amine systems were in the following order: DMT≥DHET>DMA. The polymerization rate and the percentage of conversion also increased with the increase of DMT concentration. From the kinetic investigation the rate equation of Rp=K [DMT]1/2 [MEMA]3/2 was obtained, and the overall activation energy of polymerization was calculated to be 34.3 KJ/mol (8.2 Kcal/mol). Moreover, the polymerization of MEMA in the presence of DMT was strongly inhibited by hydroquinone, indicating the polymerization being free radical in nature. From these results, the mechanism of MEMA polymerization initiated by amine was proposed.

  11. Online observation of emulsion polymerization by fluorescence technique

    CERN Document Server

    Rudschuck, S; Fuhrmann, J

    1999-01-01

    An online observation of local polarity via fluorescence spectroscopy was used to study the formation and growth of polymer particles during an emulsifier-free heterogeneous polymerization. The reaction mixture consisted of styrene dispersed in water and the polymerization was initiated by a macro-initiator (hydrolyzed propene-maleic acid copolymer with t-butyl perester groups). Pyrenyl probes were attached to the backbone of the initiator to analyze the heterogeneous reaction. The experimental results allow a clear distinction of different time regions during the heterogeneous polymerization. Information about the heating period, the latex formation, the particle growth and the final stage of the polymerization process (gel point) were obtained. (11 refs).

  12. Bridge between fusion plasma and plasma processing

    International Nuclear Information System (INIS)

    Ohno, Noriyasu; Takamura, Shuichi

    2008-01-01

    In the present review, relationship between fusion plasma and processing plasma is discussed. From boundary-plasma studies in fusion devices new applications such as high-density plasma sources, erosion of graphite in a hydrogen plasma, formation of helium bubbles in high-melting-point metals and the use of toroidal plasmas for plasma processing are emerging. The authors would like to discuss a possibility of knowledge transfer from fusion plasmas to processing plasmas. (T. Ikehata)

  13. Resveratrol immobilization and release in polymeric hydrogels

    International Nuclear Information System (INIS)

    Momesso, Roberta Grazzielli Ramos Alves Passarelli

    2010-01-01

    Resveratrol (3, 4', 5-trihydroxystilbene) is a polyphenolic produced by a wide variety of plants in response to injury and found predominantly in grape skins. This active ingredient has been shown to possess benefits for the health, such as the antioxidant capacity which is related to the prevention of several types of cancer and skin aging. However, the oral bioavailability of resveratrol is poor and makes its topical application interesting. The purpose of this study was to immobilize resveratrol in polymeric hydrogels to obtain a release device for topical use. The polymeric matrices composed of poli(N-vinyl-2-pyrrolidone) (PVP), poly(ethyleneglycol) (PEG) and agar or PVP and glycerol irradiated at 20 kGy dose were physical-chemically characterized by gel fraction and swelling tests and its preliminary biocompatibility by in vitro test of cytotoxicity using the technique of neutral red uptake. Due to low solubility of resveratrol in water, the addition of 2% ethanol to the matrices was verified. All matrices showed a high crosslinking degree, capacity of swelling and the preliminary cytotoxicity test showed nontoxicity effect. The devices were obtained by resveratrol immobilization in polymeric matrices, carried out in a one-or-two-steps process, that is, before or after irradiation, respectively. The one step resveratrol devices were characterized by gel fraction, swelling tests and preliminary biocompatibility, and their properties were maintained even after the resveratrol incorporation. The devices containing 0,05% of resveratrol obtained by one-step process and 0,1% of resveratrol obtained by two-steps process were submitted to the release test during 24 h. Resveratrol quantification was done by high performance liquid chromatography (HPLC). The results obtained in the kinetics of release showed that only the devices obtained by two-step process release the resveratrol, which demonstrate antioxidant capacity after the release. (author)

  14. Polymeric media for tritium fixation. Supplement I

    International Nuclear Information System (INIS)

    Franz, J.A.; Burger, L.L.

    1976-01-01

    Procedures for the fixation of tritium as TH or THO in two different polymeric media are described. The complete procedure for THO fixation in a polyureylene-polyurethane polumer, including polymer molding procedures and leach tests is presented. The catalytic tritiation of polystyrene under very mild conditions using a rhodium catalyst is also described. Thermal stabilities and cost estimates for the polymers examined under this program are discussed. Organic polymers were found to have attractive features for the fixation and storage of concentrated tritium wastes due to the convenience of fixation procedures and favorable properties of the resulting media

  15. Proteins and Peptides in Biomimetic Polymeric Membranes

    DEFF Research Database (Denmark)

    Perez, Alfredo Gonzalez

    2013-01-01

    This chapter discusses recent advances and the main advantages of block copolymers for functional membrane protein reconstitution in biomimetic polymeric membranes. A rational approach to the reconstitution of membrane proteins in a functional form can be addressed by a more holistic view by using...... other kind of nonbiological amphiphilic molecules. An interesting possibility could be the use of self-assembled proteins in a lipid-free membrane mimicking the capside of some viruses. The membrane proteins that have been more actively used in combination with block copolymer membranes are gramicidin...

  16. Polymeric biomaterials structure and function, v.1

    CERN Document Server

    Dumitriu, Severian

    2013-01-01

    Biomaterials have had a major impact on the practice of contemporary medicine and patient care. Growing into a major interdisciplinary effort involving chemists, biologists, engineers, and physicians, biomaterials development has enabled the creation of high-quality devices, implants, and drug carriers with greater biocompatibility and biofunctionality. The fast-paced research and increasing interest in finding new and improved biocompatible or biodegradable polymers has provided a wealth of new information, transforming this edition of Polymeric Biomaterials into a two-volume set. This volume

  17. Preparation of super absorbent by irradiation polymerization

    International Nuclear Information System (INIS)

    Hua Fengjun; Tan Chunhong; Qian Mengping

    1995-01-01

    A kind of absorbent is prepared by gamma-rays irradiated by reversed-phase suspension polymerization. Drying particles have 1400 (g/g) absorbency in de-ionic water. Effects of reactive conditions, e.g.: dose-rate, dose, monomer concentration, degree of monomer neutralization and crosslinking agents on absorbency in de-ionic water are discussed. The cause of absorbing de-ionic water by polymer is related to its network structure and ionic equilibrium in particle. Accordingly, a suit reactive condition is chosen for preparation of hydro gel spheres

  18. Immobilization of cellulase by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1983-01-01

    Immobilization of cellulase by radiation polymerization at low temperatures was studied. The enzymatic activity of immobilized cellulase pellets varied with the monomer, enzyme concentration, and the thickness of immobilized cellulase pellets. The optimum monomer concentration in the immobilization of cellulase was 30-50% at the pellet thickness of 1.0 mm, in which the enzymatic activity was 50%. The enzymatic activity of immobilized cellulase pellets was examined using various substrates such as cellobiose, carboxymethylcellulose, and paper pretreated by radiation. It was found that irradiated paper can be hydrolyzed by immobilized cellulase pellets. (author)

  19. Planar elongation of soft polymeric networks

    DEFF Research Database (Denmark)

    Jensen, Mette Krog; Hassager, Ole; Rasmussen, Henrik K.

    2010-01-01

    . To validate this new technique, soft polymeric networks of poly(propylene oxide) (PPO) were investigated during deformation. Particle tracking and video recording were used to detect to what extent the imposed strain rate and the sample perimeter remained constant. It was observed that, by using...... difference deviated more from the classical prediction due to the dynamic structures in the material. A modified Lodge model using characteristic parameters from linear viscoelastic measurements gave very good stress predictions at all Deborah numbers used in the quasi-linear regime....

  20. Polymeric Cantilever Arrays for Biosensing Applications

    DEFF Research Database (Denmark)

    Calleja, M.; Tamayo, J.; Johansson, Alicia

    2003-01-01

    We report the fabrication of arrays of polymeric cantilevers for biochemistry applications. The cantilevers are fabricated in the polymer SU-8. The use of a polymer as the component material for the cantilevers provides the sensors with very high sensitivity due to convenient mechanical material...... properties. The fabrication process is based on spin coating of the photosensitive polymer and near-ultraviolet exposure. The method allows obtaining well-controlled and uniform mechanical properties of the cantilevers. The elastic constant of the cantilevers was measured, and their dynamic response...

  1. Charpy Impact Test on Polymeric Molded Parts

    Directory of Open Access Journals (Sweden)

    Alexandra Raicu

    2012-09-01

    Full Text Available The paper presents the Charpy impact tests on the AcrylonitrileButadiene-Styrene (ABS polymeric material parts. The Charpy impact test, also known as the Charpy V-notch test, is a standardized strain rate test which determines the amount of energy absorbed by a material during fracture. This is a typical method described in ASTM Standard D 6110. We use for testing an Instron - Dynatup equipment which have a fully integrated hardware and software package that let us capture load information at very high speed from the impact tests.

  2. Polymeric materials for solar thermal applications

    CERN Document Server

    Köhl, Michael; Papillon, Philippe; Wallner, Gernot M; Saile, Sandrin

    2012-01-01

    Bridging the gap between basic science and technological applications, this is the first book devoted to polymers for solar thermal applications.Clearly divided into three major parts, the contributions are written by experts on solar thermal applications and polymer scientists alike. The first part explains the fundamentals of solar thermal energy especially for representatives of the plastics industry and researchers. Part two then goes on to provide introductory information on polymeric materials and processing for solar thermal experts. The third part combines both of these fields, dis

  3. Modelling degradation of bioresorbable polymeric medical devices

    CERN Document Server

    Pan, J

    2015-01-01

    The use of bioresorbable polymers in stents, fixation devices and tissue engineering is revolutionising medicine. Both industry and academic researchers are interested in using computer modelling to replace some experiments which are costly and time consuming. This book provides readers with a comprehensive review of modelling polymers and polymeric medical devices as an alternative to practical experiments. Chapters in part one provide readers with an overview of the fundamentals of biodegradation. Part two looks at a wide range of degradation theories for bioresorbable polymers and devices.

  4. Properties of immobilized papain by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, Minoru; Kaetsu, Isao

    1984-01-01

    Papain was immobilized by the radiation polymerization of various monomers at low temperatures and the effects of the polymer matrix on the enzyme activity and thermal stability of the immobilized enzymes were studied. The activity of the immobilized enzymes prepared from monofunctional (acrylate and methacrylate) monomers was higher than that from bifunctional (bismethacrylate) monomers and that from polyoxyethylene dimethacrylate monomers increased with an increase in the number of oxyethylene units. The thermal stability of the immobilized enzymes prepared from hydrophilic monomers was higher than that from hydrophobic monomers and increased markedly with increasing monomer concentration. (author)

  5. Radiation-induced graft polymerization of amphiphilic monomers with different polymerization characteristics onto hydrophobic polysilane

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Hidenori; Iwasaki, Isao; Kunai, Yuichiro [Research Reactor Institute, Kyoto University, Asashironishi 2-1010, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Sato, Nobuhiro, E-mail: sato-n@rri.kyoto-u.ac.j [Research Reactor Institute, Kyoto University, Asashironishi 2-1010, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Matsuyama, Tomochika [Research Reactor Institute, Kyoto University, Asashironishi 2-1010, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)

    2011-08-15

    The structures of poly(methyl-n-propylsilane) (PMPrS) amphiphilically modified through {gamma}-ray-induced graft polymerization were investigated with {sup 1}H NMR measurement. By the use of methyl methacrylate (MMA) or diethyl fumarate (DEF) as monomers for the graft polymerization, grafting yield rose with increasing total absorption dose and monomer concentrations, but decreased with increasing dose rate. This result means that grafting yield of modified PMPrS can be controlled by changing irradiation conditions. However, the number of PMMA or PDEF graft chains per PMPrS chain was estimated to be less than 1.0 by analysis of {sup 1}H NMR spectra, and this value was lower than that we had expected. To improve graft density, maleic anhydride (MAH), which is known as a non-homopolymerizable monomer in radical polymerization, was used as a monomer for grafting. As a result, high density grafting (one MAH unit for 4.2 silicon atoms) was attained. It demonstrates that the structure of {gamma}-ray-modified polysilane strongly depends on the polymerization characteristics of grafted monomers.

  6. A surface science model for the Phillips ethylene polymerization catalyst : thermal activation and polymerization activity

    NARCIS (Netherlands)

    Kimmenade, van E.M.E.; Kuiper, A.E.T.; Tamminga, Y.; Thuene, P.C.; Niemantsverdriet, J.W.

    2004-01-01

    A series of CrOx/SiO2/Si(100) model catalysts were tested for ethylene polymerization activity, varying chromium loading, and calcination temperature. Chromium coverage of the model catalyst, quantified by Rutherford backscattering spectrometry, decreases with increasing calcination temperature as

  7. Plasma waves

    National Research Council Canada - National Science Library

    Swanson, D. G

    1989-01-01

    ... Swanson, D.G. (Donald Gary), D a t e - Plasma waves. Bibliography: p. Includes index. 1. Plasma waves. QC718.5.W3S43 1989 ISBN 0-12-678955-X I. Title. 530.4'4 88-34388 Printed in the United Sta...

  8. Plasma properties

    International Nuclear Information System (INIS)

    Weitzner, H.

    1991-06-01

    The Magneto-Fluid Dynamics Division continues to study a broad range of problems originating in plasma physics. Its principal focus is fusion plasma physics, and most particularly topics of particular significance for the world magnetic fusion program. During the calendar year 1990 we explored a wide range of topics including RF-induced transport as a plasma control mechanism, edge plasma modelling, further statistical analysis of L and H mode tokamak plasmas, antenna design, simulation of the edge of a tokamak plasma and the L-H transition, interpretation of the CCT experimental results at UCLA, turbulent transport, studies in chaos, the validity of moment approximations to kinetic equations and improved neoclassical modelling. In more basic studies we examined the statistical mechanisms of Coulomb systems and applied plasma ballooning mode theory to conventional fluids in order to obtain novel fluid dynamics stability results. In space plasma physics we examined the problem of reconnection, the effect of Alfven waves in space environments, and correct formulation of boundary conditions of the Earth for waves in the ionosphere

  9. Plasma container

    International Nuclear Information System (INIS)

    Ebisawa, Katsuyuki.

    1985-01-01

    Purpose: To enable to easily detect that the thickness of material to be abraded is reduced to an allowable limit from the outerside of the plasma container even during usual operation in a plasma vessel for a thermonuclear device. Constitution: A labelled material is disposed to the inside or rear face of constituent members of a plasma container undergoing the irradiation of plasma particles. A limiter plate to be abraded in the plasma container is composed of an armour member and heat removing plate, in which the armour member is made of graphite and heat-removing plate is made of copper. If the armour member is continuously abraded under the effect of sputtering due to plasma particles, silicon nitride embedded so far in the graphite at last appears on the surface of the limiter plate to undergo the impact shocks of the plasma particles. Accordingly, abrasion of the limiter material can be detected by a detector comprising gas chromatography and it can easily be detected from the outside of the plasma content even during normal operation. (Horiuchi, T.)

  10. Application of plasma technology for the modification of polymer and textile materials

    Directory of Open Access Journals (Sweden)

    Radetić Maja M.

    2004-01-01

    Full Text Available Plasma treatment is based on the physico-chemical changes of the material surface and as an ecologically and economically acceptable process it can be an attractive alternative to conventional modifications. The possibilities of plasma technology application to the modification of polymer and textile materials are discussed. Different specific properties of the material can be achieved by plasma cleaning, etching, functionalization or polymerization. The final effects are strongly influenced by the treatment parameters (treatment time, pressure, power, gas flow, the applied gas and nature of the material. The plasma treatment of polymers is predominantly focused on cleaning and activation of the surfaces to increase adhesion, binding, wettability, dye ability and printability. Current studies deal more with plasma polymerization where an ultra thin film of plasma polymer is deposited on the material surface and, depending on the applied monomer, different specific properties can be obtained (i.e. chemical and thermal resistance, abrasion resistance, antireflexion, water repellence, etc.. Plasma application to textiles is mostly oriented toward wool and synthetic fibres, though some studies also consider cotton, hemp, flax and silk. The main goal of plasma treatment is to impart a more hydrophilic fibre surface and accordingly increase wettability, dye ability, printability and particularly, shrink resistance in the case of wool. Recent studies have favored technical textiles, where plasma polymerization can offer a wide range of opportunities.

  11. Cosmic plasma

    Energy Technology Data Exchange (ETDEWEB)

    Alfven, H [California Univ., San Diego, La Jolla (USA)

    1981-01-01

    The properties of space plasmas are analyzed, based on laboratory results and data obtained by in situ measurements in the magnetosphere (including the heliosphere). Attention is given to the question of how much knowledge can be gained by a systematic comparison of different regions of plasma, and plasmas are considered with linear dimensions varying from laboratory size up to the Hubble distance. The traditional magnetic field description of plasmas is supplemented by an electric current description and it is demonstrated that many problems are easier to understand with a dualistic approach. Using the general plasma properties obtained, the origin and evolution of the solar system is summarized and the evolution and present structure of the universe (cosmology) is discussed.

  12. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A relativistic electron beam generator or accelerator produces a high-voltage electron beam which is modulated to initiate electron bunching within the beam which is then applied to a high-density target plasma which typically comprises DT, DD, or similar thermonuclear gas at a density of 10 17 to 10 20 electrons per cubic centimeter. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region of the high-density plasma target. The high-temperature plasma can be used to heat a high Z material to generate radiation. Alternatively, a tunable radiation source is produced by using a moderate Z gas or a mixture of high Z and low Z gas as the target plasma. (author)

  13. Application of living radical polymerization to the synthesis of resist polymers for radiation lithography

    International Nuclear Information System (INIS)

    Shimizu, Takashi; Ichikawa, Tsuneki

    2005-01-01

    Poly(styrene) and poly(methyl acrylate) with benzyl ester of carboxylic acid at the center of the polymer skeletons were synthesized by living radical polymerization for developing a new type of radiation resist with high resistivity to plasma etching and high sensitivity and spatial resolution to ionizing radiations. The initiators were benzyl esters with two functional groups for living radical polymerization on the benzyl and the carboxylic sides. Introduction of benzyl ester to the polymer skeletons changed the polymers from cross-link type to scission type upon γ-irradiation. Irradiation of the polymers resulted in the binary change of the molecular weight, due to dissociative capture of secondary electrons by the benzyl ester, as M n R 1 COOCH(C 6 H 5 )R 2 M n +e - ->M n R 1 COO - + · CH(C 6 H 5 )R 2 M n . The generated polymer fragments were not decomposed by further irradiation, which suggests that the synthesized polymers have high resistivity to plasma etching

  14. Application of living radical polymerization to the synthesis of resist polymers for radiation lithography

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Takashi [Nitto Denko Co. LTD., Shimohozumi 1-1-2, Ibaraki, Osaka 567-8680 (Japan); Ichikawa, Tsuneki [Division of Materials Chemistry, Graduate school of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)]. E-mail: ichikawa@eng.hokudai.ac.jp

    2005-07-01

    Poly(styrene) and poly(methyl acrylate) with benzyl ester of carboxylic acid at the center of the polymer skeletons were synthesized by living radical polymerization for developing a new type of radiation resist with high resistivity to plasma etching and high sensitivity and spatial resolution to ionizing radiations. The initiators were benzyl esters with two functional groups for living radical polymerization on the benzyl and the carboxylic sides. Introduction of benzyl ester to the polymer skeletons changed the polymers from cross-link type to scission type upon {gamma}-irradiation. Irradiation of the polymers resulted in the binary change of the molecular weight, due to dissociative capture of secondary electrons by the benzyl ester, as M{sub n}R{sub 1}COOCH(C{sub 6}H{sub 5})R{sub 2}M{sub n}+e{sup -}->M{sub n}R{sub 1}COO{sup -}+{sup {center_dot}}CH(C{sub 6}H{sub 5})R{sub 2}M{sub n}. The generated polymer fragments were not decomposed by further irradiation, which suggests that the synthesized polymers have high resistivity to plasma etching.

  15. Superconducting plasmas

    International Nuclear Information System (INIS)

    Ohnuma, Toshiro; Ohno, J.

    1994-01-01

    Superconducting (SC) plasmas are proposed and investigated. The SC plasmas are not yet familiar and have not yet been studied. However, the existence and the importance of SC plasmas are stressed in this report. The existence of SC plasmas are found as follows. There is a fundamental property of Meissner effect in superconductors, which shows a repulsive effect of magnetic fields. Even in that case, in a microscopic view, there is a region of magnetic penetration. The penetration length λ is well-known as London's penetration depth, which is expressed as δ = (m s /μ 0 n s q s 2 ) 1/2 where m s , n s , q s and μ o show the mass, the density, the charge of SC electron and the permeability in free space, respectively. Because this expression is very simple, no one had tried it into more simple and meaningful form. Recently, one of the authors (T.O.) has found that the length can be expressed into more simple and understandable fundamental form as λ = c/ω ps where c = (ε 0 μ 0 ) -1/2 and ω ps = (n s q s 2 /m s ε 0 ) 1/2 are the light velocity and the superconducting plasma frequency. From this simple expression, the penetration depth of the magnetic field to SC is found as a SC plasma skin depth, that is, the fundamental property of SC can be expressed by the SC plasmas. This discovery indicates an importance of the studies of superconducting plasmas. From these points, several properties (propagating modes et al) of SC plasmas, which consist of SC electrons, normal electrons and lattice ions, are investigated in this report. Observations of SC plasma frequency is also reported with a use of Terahertz electromagnet-optical waves

  16. Interaction of nanosecond ultraviolet laser pulses with reactive dusty plasma

    International Nuclear Information System (INIS)

    Wetering, F. M. J. H. van de; Oosterbeek, W.; Beckers, J.; Nijdam, S.; Gibert, T.; Mikikian, M.; Rabat, H.; Kovačević, E.; Berndt, J.

    2016-01-01

    Even though UV laser pulses that irradiate a gas discharge are small compared to the plasma volume (≲3%) and plasma-on time (≲6 × 10 −6 %), they are found to dramatically change the discharge characteristics on a global scale. The reactive argon–acetylene plasma allows the growth of nanoparticles with diameters up to 1 μm, which are formed inside the discharge volume due to spontaneous polymerization reactions. It is found that the laser pulses predominantly accelerate and enhance the coagulation phase and are able to suppress the formation of a dust void.

  17. Development and Optimization of Polymeric Self-Emulsifying Nanocapsules for Localized Drug Delivery: Design of Experiment Approach

    Directory of Open Access Journals (Sweden)

    Jyoti Wadhwa

    2014-01-01

    Full Text Available The purpose of the present study was to formulate polymeric self-emulsifying curcumin nanocapsules with high encapsulation efficiency, good emulsification ability, and optimal globule size for localized targeting in the colon. Formulations were prepared using modified quasiemulsion solvent diffusion method. Concentration of formulation variables, namely, X1 (oil, X2 (polymeric emulsifier, and X3 (adsorbent, was optimized by design of experiments using Box-Behnken design, for its impact on mean globule size (Y1 and encapsulation efficiency (Y2 of the formulation. Polymeric nanocapsules with an average diameter of 100–180 nm and an encapsulation efficiency of 64.85 ± 0.12% were obtained. In vitro studies revealed that formulations released the drug after 5 h lag time corresponding to the time to reach the colonic region. Pronounced localized action was inferred from the plasma concentration profile (Cmax 200 ng/mL that depicts limited systemic absorption. Roentgenography study confirms the localized presence of carrier (0–2 h in upper GIT; 2–4 h in small intestine; and 4–24 h in the lower intestine. Optimized formulation showed significantly higher cytotoxicity (IC50 value 20.32 μM in HT 29 colonic cancer cell line. The present study demonstrates systematic development of polymeric self-emulsifying nanocapsule formulation of curcumin for localized targeting in colon.

  18. Numerical simulation of anisotropic polymeric foams

    Directory of Open Access Journals (Sweden)

    Volnei Tita

    Full Text Available This paper shows in detail the modelling of anisotropic polymeric foam under compression and tension loadings, including discussions on isotropic material models and the entire procedure to calibrate the parameters involved. First, specimens of poly(vinyl chloride (PVC foam were investigated through experimental analyses in order to understand the mechanical behavior of this anisotropic material. Then, isotropic material models available in the commercial software AbaqusTM were investigated in order to verify their ability to model anisotropic foams and how the parameters involved can influence the results. Due to anisotropy, it is possible to obtain different values for the same parameter in the calibration process. The obtained set of parameters are used to calibrate the model according to the application of the structure. The models investigated showed minor and major limitations to simulate the mechanical behavior of anisotropic PVC foams under compression, tension and multi-axial loadings. Results show that the calibration process and the choice of the material model applied to the polymeric foam can provide good quantitative results and save project time. Results also indicate what kind and order of error one will get if certain choices are made throughout the modelling process. Finally, even though the developed calibration procedure is applied to specific PVC foam, it still outlines a very broad drill to analyze other anisotropic cellular materials.

  19. Functionalized nanoparticle interactions with polymeric membranes.

    Science.gov (United States)

    Ladner, D A; Steele, M; Weir, A; Hristovski, K; Westerhoff, P

    2012-04-15

    A series of experiments was performed to measure the retention of a class of functionalized nanoparticles (NPs) on porous (microfiltration and ultrafiltration) membranes. The findings impact engineered water and wastewater treatment using membrane technology, characterization and analytical schemes for NP detection, and the use of NPs in waste treatment scenarios. The NPs studied were composed of silver, titanium dioxide, and gold; had organic coatings to yield either positive or negative surface charge; and were between 2 and 10nm in diameter. NP solutions were applied to polymeric membranes composed of different materials and pore sizes (ranging from ≈ 2 nm [3 kDa molecular weight cutoff] to 0.2 μm). Greater than 99% rejection was observed of positively charged NPs by negatively charged membranes even though pore diameters were up to 20 times the NP diameter; thus, sorption caused rejection. Negatively charged NPs were less well rejected, but behavior was dependent not only on surface functionality but on NP core material (Ag, TiO(2), or Au). NP rejection depended more upon NP properties than membrane properties; all of the negatively charged polymeric membranes behaved similarly. The NP-membrane interaction behavior fell into four categories, which are defined and described here. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Degradable polymeric materials for osteosynthesis: Tutorial

    Directory of Open Access Journals (Sweden)

    D Eglin

    2008-12-01

    Full Text Available This report summarizes the state of the art and recent developments and advances in the use of degradable polymers devices for osteosynthesis. The current generation of biodegradable polymeric implants for bone repair utilising designs copied from metal implants, originates from the concept that devices should be supportive and as “inert” substitute to bone tissue. Today degradable polymeric devices for osteosynthesis are successful in low or mild load bearing applications. However, the lack of carefully controlled randomized prospective trials that document their efficacy in treating a particular fracture pattern is still an issue. Then, the choice between degradable and non-degradable devices must be carefully weighed and depends on many factors such as the patient age and condition, the type of fracture, the risk of infection, etc. The improvement of the biodegradable devices mechanical properties and their degradation behaviour will have to be achieved to broaden their use. The next generation of biodegradable implants will probably see the implementation of the recent gained knowledge in cell-material interactions and cells therapy, with a better control of the spatial and temporal interfaces between the material and the surrounding bone tissue.