WorldWideScience

Sample records for acrylic acid

  1. Acrylic Acid and Esters Will Be Oversupply

    Institute of Scientific and Technical Information of China (English)

    Zheng Chengwang

    2007-01-01

    @@ Drastic capacity growth The production capacity of acrylic acid in China has grown drastically in recent years. With the completion of the 80 thousand t/a acrylic acid and 130 thous and t/a acrylic ester project in Shenyang Paraffin Chemical Industrial Co., Ltd., (CCR2006,No. 31) the capacity of acrylic acid in China has reached 882 thousand t/a.

  2. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid...

  3. Investigation of Acrylic Acid at High Pressure using Neutron Diffraction

    DEFF Research Database (Denmark)

    Johnston, Blair F.; Marshall, William G.; Parsons, Simon;

    2014-01-01

    This article details the exploration of perdeuterated acrylic acid at high pressure using neutron diffraction. The structural changes that occur in acrylic acid-d4 are followed via diffraction and rationalised using the Pixel method. Acrylic acid undergoes a reconstructive phase transition to a n...

  4. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylamide-acrylic acid resins. 176.110 Section 176... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in...

  5. Rare linking hydrogels based on acrylic acid and carbohydrate esters

    Directory of Open Access Journals (Sweden)

    U. Akhmedov

    2012-09-01

    Full Text Available The process of copolymerization of acrylic acid and esters poliallil sucrose; pentaerythritol and sorbitol, some of its laws are identified. The kinetic regularities of copolymerization and the optimum conditions of synthesis was established.

  6. Antimicrobial activity of poly(acrylic acid) block copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Gratzl, Günther, E-mail: guenther.gratzl@jku.at [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Paulik, Christian [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Hild, Sabine [Johannes Kepler University Linz, Institute of Polymer Science, Altenberger Str. 69, 4040 Linz (Austria); Guggenbichler, Josef P.; Lackner, Maximilian [AMiSTec GmbH and Co. KG, Leitweg 13, 6345 Kössen, Tirol (Austria)

    2014-05-01

    The increasing number of antibiotic-resistant bacterial strains has developed into a major health problem. In particular, biofilms are the main reason for hospital-acquired infections and diseases. Once formed, biofilms are difficult to remove as they have specific defense mechanisms against antimicrobial agents. Antimicrobial surfaces must therefore kill or repel bacteria before they can settle to form a biofilm. In this study, we describe that poly(acrylic acid) (PAA) containing diblock copolymers can kill bacteria and prevent from biofilm formation. The PAA diblock copolymers with poly(styrene) and poly(methyl methacrylate) were synthesized via anionic polymerization of tert-butyl acrylate with styrene or methyl methacrylate and subsequent acid-catalyzed hydrolysis of the tert-butyl ester. The copolymers were characterized via nuclear magnetic resonance spectroscopy (NMR), size-exclusion chromatography (SEC), Fourier transform infrared spectroscopy (FTIR), elemental analysis, and acid–base titrations. Copolymer films with a variety of acrylic acid contents were produced by solvent casting, characterized by atomic force microscopy (AFM) and tested for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The antimicrobial activity of the acidic diblock copolymers increased with increasing acrylic acid content, independent of the copolymer-partner, the chain length and the nanostructure. - Highlights: • Acrylic acid diblock copolymers are antimicrobially active. • The antimicrobial activity depends on the acrylic acid content in the copolymer. • No salts, metals or other antimicrobial agents are needed.

  7. Intercalation of acrylic acid and sodium acrylate into kaolinite and their in situ polymerization

    Science.gov (United States)

    Zhang, Bo; Li, Yanfeng; Pan, Xiaobing; Jia, Xin; Wang, Xiaolong

    2007-02-01

    Novel nano-composites of poly (acrylic acid)-kaolinite were prepared, and intercalation and in situ polymerization were used in this process. The nano-composites were obtained by in situ polymerization of acrylic acid (AA) and sodium acrylate (AANa) intercalated into organo-kaolinite, which was obtained by refining and chemically modifying with solution intercalation step in order to increase the basal plane distance of the original clay. The modification was completed by using dimethyl-sulfoxide (DMSO)/methanol and potassium acetate (KAc)/water systems step by step. The materials were characterized with the help of XRD, FT-IR and TEM; the results confirmed that poly(acrylic acid) (PAA) and poly(sodium acrylate) (PAANa) were intercalated into the interlamellar spaces of kaolinite, the resulting copolymer composites (CC0 : copolymer crude kaolinite composite, CC1 : copolymer DMSO kaolinite composite, CC2 : copolymer KAc kaolinite composite) of CC2 exhibited a lamellar nano-composite with a mixed nano-morphology, and partial exfoliation of the intercalating clay platelets should be the main morphology. Finally, the effect of neutralization degree on the intercalation behavior was also investigated.

  8. COMPLEX OXIDE CATALYSTS OF ACRYLIC ACID OBTAINING BY ALDOL CONDENSATION METHOD

    OpenAIRE

    Nebesnyi, R.

    2015-01-01

    The present work is dedicated to solving the problem of diversification of the raw materials base for acrylate monomers obtaining,  first of all acrylic acid. Acrylic acid and its derivatives are bulk products of organic synthesis with a wide range of applications. The main industrial method of acrylic acid production is  propylene oxidation. But this method has instable economic indicators as propylene is petroleum origin raw material.It is possible to expand the resource base of acrylic aci...

  9. Decarboxylation-based traceless linking with aroyl acrylic acids

    DEFF Research Database (Denmark)

    Nielsen, John

    1998-01-01

    beta-Keto carboxylic acids are known to decarboxylate readily. In our pursuit to synthesize beta-indolinyl propiophenones, we have exploited this chemistry as a mean of establishing a traceless handle. 2-Aroyl acrylic acids have been esterified to a trityl resin, after which Michael-type addition...

  10. 40 CFR 721.9640 - Salt of an acrylic acid - acrylamide terpolymer (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Salt of an acrylic acid - acrylamide... Specific Chemical Substances § 721.9640 Salt of an acrylic acid - acrylamide terpolymer (generic). (a... generically as salt of an acrylic acid - acrylamide terpolymer (PMN P-99-817) is subject to reporting...

  11. Use of Acrylic Acid Sodium Acrylate Polymer to Maintain Cocoa Seed Viability

    Directory of Open Access Journals (Sweden)

    Pudji Rahardjo

    2010-08-01

    Full Text Available The main problem of cocoa seed storage is moisture content of the seeds because cocoa seeds will germinate if cocoa seeds moisture content is high. The objective of this research is to maintain the cocoa seeds viability in storage using acrylic acid sodium acrylate polymer (AASAP. The function of AASAP is to absorb humidity in storage due to their ability to retain water and to prevent water loss. The experiment was conducted in a laboratory of Indonesian Coffee and Cocoa Research Institute and in Kaliwining Experimental Garden. This experiment was arranged by factorial randomized complete design, in wich AASAP dosages 0%; 0.1% (0.1 g/100 seeds; 0.2% (0.2 g/100 seeds, 0.3% (0.3 g/100 seeds, 0,4% (0,4g/100 seeds, combined with seeds storage period 1, 2, 3 and 4 weeks. The experiment used 3 replications and each repli cation used 100 seeds. Parameter of observation consisted of percentage of seeds germinated in storage, percentage of seeds infected by fungi in storage, seeds moisture content, percentage of seeds germination after storage, and early growth of cocoa seedlings. The results of the experiment showed that AASAP application with some dosages cocoa seeds storage cause to germinate in storage during 2 weeks. AASAP application with some dosages in cocoa seeds storage for 2 weeks would not result in infection by fungi and did not significantly affect seed germination after storage for 1, 2 and 4 weeks, and percentage of germination of cocoa seed after storage for 3 weeks decreased with increase dosage of AASAP. Higher dosage of AASAP would reduce early growth of cocoa seedling. Key words : Theobroma cacao, seed, acrylic acid sodium acrylate, seed storage, viabilty.

  12. Acrylic acid obtaining from methanol and acetic acid in the presence of complex oxide catalysts

    OpenAIRE

    Небесний, Роман Володимирович; Піх, Зорян Григорович; Шпирка, Ірина Іванівна; Івасів, Володимир Васильович; Небесна, Юлія Віталіївна; Фуч, Уляна Василівна

    2015-01-01

    The purpose of this work is to research process of single-stage acrylic acid obtaining from methanol and acetic acid, namely: to develop effective catalysts for the process of methanol oxidation to formaldehyde with its further aldol condensation with acetic acid to acrylic acid, and to determine optimum conditions for the process. Complex oxide catalysts consisting of oxides of boron, phosphorus, tungsten and vanadium supported on the silica gel have been investigated. The effect of vanadium...

  13. Scientific Opinion on the safety evaluation of the active substance, acrylic acid, sodium salt, co-polymer with acrylic acid, methyl ester, methacrylic acid, 2 hydroxypropylester, and acrylic acid cross-linked for use in active food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the acrylic acid, sodium salt, co-polymer with acrylic acid, methyl ester, methacrylic acid, 2 hydroxypropylester, and acrylic acid cross-linked (CAS No. 117675-55-5, FCM Substance No 1022, to be used as liquid absorber in the form of fibres in absorbent pads for the packaging of fresh or frozen meat, poultry, and fish as well as fresh fruits and vegetables. The Panel considered that migration is not expected when the absorption capacity of the pads is not exceeded. Therefore no exposure from the consumption of the packed food is expected. The Panel also considered that none of these starting substances and the cross-linked polymer gives rise to concern for genotoxicity. Therefore the CEF Panel concluded that the use of the substance acrylic acid, sodium salt, co-polymer with acrylic acid, methyl ester, methacrylic acid, 2 hydroxypropylester, and acrylic acid cross-linked does not raise a safety concern when used as fibres in absorber pads for the packaging of fresh or frozen meat, poultry, fish, fruits and vegetables under conditions under which the absorption capacity of the pads is not exceeded and mechanical release of the fibres from the pads is excluded.

  14. Reactivity Ratios of Diethyldiallylammonium Chloride with Acrylamide or Acrylic Acid

    Institute of Scientific and Technical Information of China (English)

    Li Hua LIU; Zhi Qiang LIU; Zhu Qing GONG

    2006-01-01

    The compositions of copolymers of diethyldiallylammonium chloride (DEDAAC) with acrylamide (AM), acrylic acid (AA) or sodium acrylic acid (NaAA) at low conversion were determined by elemental analysis, and the reactivity ratios of monomers in copolymerization were obtained by Kelen-Tudos method. The results showed that the reactivity ratios rDE and rAM are 0.31 and 5.27 for DEDAAC with AM, rDE and rAA are 0.28 and 5.15 for DEDAAC with AA, and rDE and rNaAA are 0.40 and 3.97 for DEDAAC with NaAA, respectively. The copolymerizations for DEDAAC with AM, AA or NaAA are non-ideal copolymerization and the products are random copolymers.

  15. A New Process for Acrylic Acid Synthesis by Fermentative Process

    Science.gov (United States)

    Lunelli, B. H.; Duarte, E. R.; de Toledo, E. C. Vasco; Wolf Maciel, M. R.; Maciel Filho, R.

    With the synthesis of chemical products through biotechnological processes, it is possible to discover and to explore innumerable routes that can be used to obtain products of high addes value. Each route may have particular advantages in obtaining a desired product, compared with others, especially in terms of yield, productivity, easiness to separate the product, economy, and environmental impact. The purpose of this work is the development of a deterministic model for the biochemical synthesis of acrylic acid in order to explore an alternative process. The model is built-up with the tubular reactor equations together with the kinetic representation based on the structured model. The proposed process makes possible to obtain acrylic acid continuously from the sugar cane fermentation.

  16. Surface cross-linked humic acid - polysodium acrylate superabsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Chu, M.; Zhu, S.; Li, H.; Huang, Z.; Zhang, X. [China University of Mining and Technology, Beijing (China)

    2005-03-01

    A novel composite super-absorbent of humic acid-polysodium acrylate was invented by surface cross-linking reaction of lignite humic acid and poly. Humic acid was abstracted from leonardite and poly was synthesized by solution polymerization. Water absorbing mechanism of composite superabsorbent was explored based on FTIR and SEM. The effect of surface cross-linking reaction conditions, such as the ratio of methanol to water, cross-linking agent concentration, and the amount of humic acid on water absorbing were investigated. Experiments show that the water absorbency of superabsorbent can be greatly improved by humic acid. When the mass fraction of humic acid is 10%, the ratio of cross-linking agent to PSA is 0.2%, and the ratio of methanol to water is 1.8, the water absorbency is the best: 750 g/g for deionied water and 260 g/g for running. water. 9 refs., 5 figs., 1 tab.

  17. Positron annihilation study of acryl amide/poly (metha acrylic acid) membrane

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Hady, E E; Abdel-Hamed, M O; Hammam, A M; Elsharkawy, M R M [Physics Department, Faculty of Science, Minia University, Minia (Egypt); Eltoony, M M, E-mail: esamhady@yahoo.com [Chemistry Department, Atomic Energy Authority, Cairo 11115 (Egypt)

    2011-01-01

    Gamma irradiation posses a serious role for casting the membranes. Acryl amide /poly (methacrylic acid) membrane was synthesized under {gamma}-radiation effect. The structure of the membrane was characterized by FTIR, thermo-gravimetric analysis and the scanning electron microscope. The properties of the membranes were also investigated in terms of proton conductivity and positron annihilation lifetime (PAL) parameters. On the basis of the values of the long-lived components in the lifetime spectra, the size of the free volume and their intensity were calculated. The positron lifetime study on these irradiated casted membranes shows that the cross-linking and degradation within the membrane matrix affect the free volume content and hence the microstructure.

  18. Poly(styrene-acrylic acid) magnetic polymer microspheres

    Institute of Scientific and Technical Information of China (English)

    Yanling CHENG; Liuqiang MA; Ruohui LI

    2008-01-01

    Magnetic polymer microspheres have been considered as a kind of new biopolymer materials with great advantages in bioseparation engineering and biome-dicine engineering because they have not only polymer functional groups but also magnetic characteristics. Styrene-acrylic acid copolymer (p(S-AA)) magnetic microspheres were synthesized by dispersion polymeriza-tion with Fe3O4 as core and p(S-AA) as shell. The micro-spheres were characterized by SEM, size analysis, molecular weight and solid content measurement. All of them indicate that the microspheres are small in size, nar-row in distribution, stable in chemistry and rich in func-tional groups on their surface.

  19. Conformational Transition of Poly (Acrylic Acid) Detected by Microcantilever Sensing

    Institute of Scientific and Technical Information of China (English)

    LI Kai; LIU Hong; ZHANG Qing-Chuan; XUE Chang-Guo; WU Xiao-Ping

    2007-01-01

    Poly (acrylic acid) (PAA) chains are grafted on one side of a microcantilever by the self-assembled method and the deflections of the microcantilever are detected as a function of medium pH from 3 to 11. It is found that when the pH varies, the microcantilever deflects because of the changing surface stress. By analysing the electrostatic repulsive effect, the surface stress change is related to the conformation transition of PAA from a collapse state to a swelling state. This method offers the interaction information among the polymer chains during the conformational transition and affords an alternative way to study conformational change of polymers.

  20. Graft copolymerization of acrylic acid onto polyamide fibers

    Science.gov (United States)

    Makhlouf, Chahira; Marais, Stéphane; Roudesli, Sadok

    2007-04-01

    The grafting of acrylic acid (AA) monomer (CH 2dbnd CH sbnd COOH) on polyamide 6.6 monofilaments (PA 6.6) using benzoyl peroxide (BPO) as initiator was carried out in order to enhance the hydrophilic nature of fibers. The grafting rate depends on the AA concentration, the BPO concentration, the time and the temperature of reaction. The best conditions for optimum rate of grafting were obtained with a AA concentration of 0.5 M, a BPO concentration of 0.03 M, a reaction temperature of T = 85 °C and a reaction time of 120 mn. The fiber surface has been investigated by many experimental techniques of characterization such as Fourier transform infrared spectroscopy (FTIR), calorimetric analysis (DSC), scanning electron microscopy (SEM), and contact angle measurements. The effect of grafting of acrylic acid onto PA 6.6 fibers on their moisture and mechanical resistances was analyzed from water sorption and elongation at break measurements. The analysis of the experimental data shows clearly the efficiency of the grafting reaction used, leading to a significant increase of the hydrophilic character of the PA 6.6 surface.

  1. Plasma polymerization of acrylic acid onto polystyrene by cyclonic plasma at atmospheric pressure

    Science.gov (United States)

    Chang, Yi-Jan; Lin, Chin-Ho; Huang, Chun

    2016-01-01

    The cyclonic atmospheric-pressure plasma is developed for chamberless deposition of poly(acrylic acid) film from argon/acrylic acid mixtures. The photoemission plasma species in atmospheric-pressure plasma polymerization was identified by optical emission spectroscopy (OES). The OES diagnosis data and deposition results indicated that in glow discharge, the CH and C2 species resulted from low-energy electron-impact dissociation that creates deposition species, but the strong CO emission lines are related to nondeposition species. The acrylic acid flow rate is seen as the key factor affecting the film growth. The film surface analysis results indicate that a smooth, continuous, and uniform surface of poly(acrylic acid) films can be formed at a relatively low plasma power input. This study reveals the potential of chamberless film growth at atmospheric pressure for large-area deposition of poly(acrylic acid) films.

  2. New initiation system for polymerization of acryl acid

    Institute of Scientific and Technical Information of China (English)

    LI Hai-pu; ZHONG Hong; CHEN Qi-yuan; YIN Zhou-lan

    2005-01-01

    The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.

  3. Polymerisation by acrylamide and acrylic acid inverse suspension

    Directory of Open Access Journals (Sweden)

    Sergio Alejandro LLoreda Blanco

    2010-04-01

    Full Text Available This work describes polymerisation by inverse suspension of acrylamide monomers and acrylic acid for forming homopolymers or copolymers This type of polymersitaion's advantages are described and reasons given for why it should be studied. The article stresses the importance of these types of monomer for obtaining materials presenting great affinity for water, such as super-absorbents and controlled liberation mechanism. Important aspects are presented such as type of initiation, monomer composition and continuous phase composition; parameters are described offering an important basis for formulating a system leading to successfully obtaining the desired materials' most relevant characteristics such as particle distribution and size polymerisation kinetics, conversion and water absorption capacity respecting the system's modifiable parameters. The foregoing is important since the product can be modified, bestowing propierties on it which are suitable for its use.

  4. Swelling Behaviors of Polyaniline-Poly(Acrylic Acid) Hydrogels

    Institute of Scientific and Technical Information of China (English)

    ZHANG You-wei; ZHAO Jiong-xin; LI Xiao-feng; TAO Yong; WU Cheng-xun

    2005-01-01

    Using poly(acrylic acid) (PAA) aqueous solution, NaOH aqueous solution, aniline(An) and ammonim persulfate(APS), PAn-PAA hydrogels with a semi-interpenetrating structure connected by physical interlocks, chemical ion bonds and hydrogen bonds wcre prepared. The swelling properties of the hydrogels in solutions of different pH values(adjusted by adding NaOH or HCl) were studied. All the hydrogels prepared have similar swelling curves (the curves of equilibrium swelling ratio vs. pH value) and reach their maximum swelling at pH of 8 - 10. The maximum swelling ratio of the hydrogels is dependent on composition, including molecular weight of PAA, polymer content of the hydrogel,and molar ratios of AA to An, APS to An, and NaOH to AA.And the compositional dependence of the swelling capacity of PAn-PAA hydrogels was also studied.

  5. Copolymerization of Indene with Acrylic Acid, Itaconic Acid and Acrylonitrile: Characterization and Reactivity Ratios

    International Nuclear Information System (INIS)

    Random copolymers of indene (In) with acrylic acid (AA), itaconic acid (IA) and acrylonitrile (AN) were synthesized by free radical polymerization in dioxane in the presence of azobisisobutyronitrile as an initiator at 60 degree C. The homopolymer of indene and acrylonitrile was prepared using K2MnO4 and sulphuric acid as an initiator, while acrylic acid and itaconic acid were prepared using K2S2O8 solution. The reactivity ratios of the monomers were calculated by different methods. X-ray diffraction as well as thermal analyses were studied. The latter was studied via thermogravimetric analysis and differential thermal analysis. The complexation with metal ions such as Cu+2 and Fe+2 was investigated. The copolymerization and the complexation processes were confirmed by FTIR spectroscopy. Also the activation energy of the prepared copolymers was determined

  6. Effects of composition and layer thickness of a butyl acrylate/acrylic acid copolymer on the adhesion properties

    Energy Technology Data Exchange (ETDEWEB)

    Ghim, Deoukchen; Kim, Jung Hyeun [University of Seoul, Seoul (Korea, Republic of)

    2016-02-15

    Acrylic pressure-sensitive adhesives are synthesized by solution copolymerization using n-butyl acrylate and acrylic acid (AA) in ethyl acetate anhydrous. The copolymer composition is controlled for good adhesive properties by varying AA content. The monomer conversion is measured by the gravimetric method and FTIR technique. The adhesive layer thickness is measured by scanning electron microscopy, and the adhesive properties are evaluated with loop tack, 180 .deg. peel, and holding time measurements. The peel force increases with increasing the AA content up to 3 wt% and decreases at the AA content higher than 3 wt%, but the tack force decreases with increasing the AA content. The holding time increases with increasing the AA content, and it shows a similar trend with the T{sub g} of adhesives. The increase of layer thickness improves tack and peel forces, but it weakens the holding power. A tape thickness of about 20 μm shows well-balanced properties at 3 wt% AA content in the acrylic copolymer system.

  7. Catalytic routes towards acrylic acid, adipic acid and epsilon-caprolactam starting from biorenewables

    OpenAIRE

    Beerthuis, R.; Rothenberg, G.; Shiju, N.R.

    2015-01-01

    The majority of bulk chemicals are derived from crude oil, but the move to biorenewable resources is gaining both societal and commercial interest. Reviewing this transition, we first summarise the types of today's biomass sources and their economical relevance. Then, we assess the biobased productions of three important bulk chemicals: acrylic acid, adipic acid and epsilon-caprolactam. These are the key monomers for high-end polymers (polyacrylates, nylon 6.6 and nylon 6, respectively) and a...

  8. Poly (ethylene oxide)-block-poly (n-butyl acrylate)-blockpoly (acrylic acid) triblock terpolymers with highly asymmetric hydrophilic blocks: synthesis and aqueous solution properties

    OpenAIRE

    Petrov, P; Yoncheva, K. (Krassimira); Mokreva, P. (Pavlina); Konstantinov, S.; J M Irache; Müller, A.H.E. (Axel H.E.)

    2013-01-01

    The synthesis and aggregation behaviour in aqueous media of novel amphiphilic poly(ethylene oxide)- block-poly(n-butyl acrylate)-block-poly(acrylic acid) (PEO–PnBA–PAA) triblock terpolymers were studied. Terpolymers composed of two highly asymmetric hydrophilic PEO (113 monomer units) and PAA (10–17 units) blocks, and a longer soft hydrophobic PnBA block (163 or 223 units) were synthesized by atom transfer radical polymerisation (ATRP) of n-butyl acrylate and tert-butyl acrylate ...

  9. CATALYTIC HYDROGENATION OF ACRYLATE ASMMETRIC Dd(Ⅱ)—CHELATING RESINS CONTAINING AMINO ACID LIGANDS

    Institute of Scientific and Technical Information of China (English)

    Wangying; WangHongzuo; 等

    1995-01-01

    The catalytic hydrogenation of palladium chelating resins containing chiral amino acid ligands based on lower crosslinked poly(chloroethyl acrylate) and some effects on the rate of hydrogenation were studied.

  10. Studies on LCST of poly (N-isopropylacrylamide-co-acrylic acid-co-N-diacetone acrylamide)

    Institute of Scientific and Technical Information of China (English)

    Cai Hua Ni; Xiao Xia Zhu; Qing Lan Wang; Xian Yu Zeng

    2007-01-01

    Linear copolymers from N-isopropylacrylamide (NIPA), acrylic acid (AA) and diacetone acrylamide (DAA) have been prepared.The effect of composition, ionic strength and pH on their lower critical solution temperature (LCST) has been investigated.

  11. FT-RAMAN SPECTROSCOPY FOR MONITORING THE POLYMERIZATION OF ACRYLIC ACID IN AQUEOUS SOLUTION

    Institute of Scientific and Technical Information of China (English)

    Jiang Yu; Hui-zhou Liu; Jia-yong Chen

    1999-01-01

    FT-Raman spectroscopy was used to monitor the polymerization of acrylic acid in aqueous solution. A simple method to avoid the noise in the background during the signal processing via Fourier transformation was used in this work. The effects of the amount of initiator used on the polymerization are studied. When the amount of the initiator in the polymerization was increased, both the rate and extent of polymerization of acrylic acid will be increased.

  12. Synthesis and Properties of IPN Hydrogels Based on Konjac Glucomannan and Poly(acrylic acid)

    Institute of Scientific and Technical Information of China (English)

    Bing LIU; Zhi Lan LIU; Ren Xi ZHUO

    2006-01-01

    Novel interpenetrating polymer network (IPN) hydrogels based on konjac glucomannan (KGM) and poly(acrylic acid) (PAA) were prepared by polymerization and cross-linking of acrylic acid (AA) in the pre-fabricated KGM gel. The IPN gel was analyzed by FT-IR. The studies on the equilibrium swelling ratio of IPN hydrogels revealed their sensitive response to environmental pH value. The results of in vitro degradation showed that the IPN hydrogels retain the enzymatic degradation character of KGM.

  13. Interaction of photosensitive surfactant with DNA and poly acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Zakrevskyy, Yuriy, E-mail: yuriy.zakrevskyy@fh-koeln.de; Paasche, Jens; Lomadze, Nino; Santer, Svetlana, E-mail: santer@uni-potsdam.de [Experimental Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Germany); Cywinski, Piotr; Cywinska, Magdalena; Reich, Oliver; Löhmannsröben, Hans-Gerd [Physical Chemistry, Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Germany)

    2014-01-28

    In this paper, we investigate interactions and phase transitions in polyelectrolyte-surfactant complexes formed between a cationic azobenzene-containing surfactant and two types of polyelectrolytes: natural (DNA) or synthetic (PAA: poly acrylic acid). The construction of a phase diagram allowed distancing between four major phases: extended coil conformation, colloidally stable compacted globules, colloidal instability range, and surfactant-stabilized compact state. Investigation on the complexes’ properties in different phases and under irradiation with UV light provides information about the role of the surfactant's hydrophobic trans isomers both in the formation and destruction of DNA and PAA globules as well as in their colloidal stabilization. The trans isomer shows much stronger affinity to the polyelectrolytes than the hydrophilic cis counterpart. There is no need for complete compensation of the polyelectrolyte charges to reach the complete compaction. On contrary to the findings previously reported in the literature, we demonstrate – for the first time – complete polyelectrolyte compaction which occurs already at 20% of DNA (and at 50% of PAA) charge compensation. The trans isomer plays the main role in the compaction. The aggregation between azobenzene units in the photosensitive surfactant is a driving force of this process. The decompaction can be realized during UV light irradiation and is strongly influenced by the interplay between surfactant-surfactant and surfactant-DNA interactions in the compacted globules.

  14. Radiation-induced grafting of acrylic acid onto polypropylene film and its biodegradability

    Science.gov (United States)

    Mandal, Dev K.; Bhunia, Haripada; Bajpai, Pramod K.; Chaudhari, C. V.; Dubey, K. A.; Varshney, L.

    2016-06-01

    Polypropylene based commodity polyolefins are widely used in packaging, manufacturing, electrical, pharmaceutical and other applications. The aim of the present work is to study the effect of grafting of acrylic acid on the biodegradability of acrylic acid grafted polypropylene. The effect of different conditions showed that grafting percentage increased with increase in monomer concentration, radiation dose and inhibitor concentration but decreased with increase in radiation dose rate. The maximum grafting of 159.4% could be achieved at optimum conditions. The structure of grafted polypropylene films at different degree of grafting was characterized by EDS, FTIR, TGA, DSC, SEM and XRD. EDS studies showed that the increase in acrylic acid grafting percentage increased the hydrophilicity of the grafted films. FTIR studies indicated the presence of acrylic acid on the surface of polypropylene film. TGA studies revealed that thermal stability decreased with increase in grafting percentage. DSC studies showed that melting temperature and crystallinity of the grafted polypropylene films lower than polypropylene film. SEM studies indicated that increase in acrylic acid grafting percentage increased the wrinkles in the grafted films. The maximum biodegradability could be achieved to 6.85% for 90.5% grafting. This suggested that microorganisms present in the compost could biodegrade acrylic acid grafted polypropylene.

  15. Radiation sensitive acrylate composition

    International Nuclear Information System (INIS)

    This application relates to radiation-sensitive compositions and more particularly to such compositions comprising acrylated esters. As used in this specification, the term acrylated esters refers to either acrylic or methacrylic acid resins. 3 tabs

  16. Radiation modification of water absorption of cassava starch by acrylic acid/acrylamide

    International Nuclear Information System (INIS)

    Graft co polymerizations of acrylamide and/or acrylic acid onto cassava starch by a simultaneous irradiation technique using gamma-rays as the initiator were studied with regard to various parameters of importance: the monomer-to-cassava starch ratio, total dose (kGy), dose rate (kGy h-1), acrylamide-to-acrylic acid ratio, and the addition of nitric acid and maleic acid as the additives. Grafting parameters were determined in relation to the water absorption of the saponified graft copolymer. The water absorption of the saponified graft copolymer in salt and buffer solutions of different ionic strengths was also measured, from which the super absorbent properties are found to be P H sensitive. The starch graft copolymers of acrylamide and acrylic acid give higher water absorption than the starch graft copolymers of either acrylamide or acrylic acid alone. The porosity of the saponified starch graft copolymers prepared by the acrylamide/acrylic acid ratios of 70:30 and 50:50 was much higher than the porosity of copolymers in terms of fine networks. Ionic strength and multi-oxidation states of the saline and buffer solutions markedly decreased the water absorption of the saponified cassava starch grafted super absorbent polymers.

  17. Polymorphism and polymerisation of acrylic and methacrylic acid at high pressure

    DEFF Research Database (Denmark)

    Oswald, Iain D. H.; Urquhart, Andrew J.

    2011-01-01

    The polymorphism and polymerisation of two related acids have been investigated under high pressure conditions. Acrylic acid crystallises as a new polymorph at 0.65 GPa whilst methacrylic acid crystallises in a new polymorph at a higher pressure of 1.5 GPa. Both these new polymorphs exhibit similar...

  18. Acidic polyanion poly(acrylic acid) prevents calcium oxalate crystal deposition

    OpenAIRE

    Kleinman, Jack G.; Alatalo, Laura J.; Beshensky, Ann M.; Wesson, Jeffrey A.

    2008-01-01

    Acidic macromolecules inhibit calcium oxalate nucleation, growth, aggregation and attachment to cells in vitro. To test for such an effect in vivo we used osmotic minipumps to continuously infuse several doses of the 5.1 kDa poly(acrylic acid) (pAA5.1) into rats fed a diet which causes renal calcium oxalate crystal deposition. Although kidneys of rats receiving the saline control contained calcium oxalate crystals, measured by polarized light microscopy, those of animals given pAA5.1 had sign...

  19. Covalent Functionalization of Multiwalled Carbon Nanotubes with Poly(acrylic acid)

    Institute of Scientific and Technical Information of China (English)

    LIU, Yan-Xin; DU, Zhong-Jie; LI, Yan; ZHANG, Chen; LI, Hang-Quan

    2006-01-01

    Covalent functionalization of multiwalled carbon nanotubes (MWNT) with poly(acrylic acid) has been successfully achieved via grafting of poly(acryloyl chloride) on nanotube surface by esterification reaction of acyl chloride-bound polymer with hydroxyl functional groups present on acid-oxidized MWNT and hydrolysis of polymer attached to nanotubes. Polymer-functionalized MWNT could possess remarkably high solubility in water, and their aqueous solution was very stable without any observable black deposit for a long time. Characterizations of such functionalized MWNT samples using Fourier transform infrared spectrometer, transmission electron microscopy and nuclear magnetic resonance techniques indicated that poly(acrylic acid) was covalently attached to the surface of MWNT.

  20. Direct Synthesis of Hyperbranched Poly(acrylic acid-co-3-hydroxypropionate

    Directory of Open Access Journals (Sweden)

    Efkan Çatıker

    2015-01-01

    Full Text Available Hyperbranched poly(acrylic acid-co-3-hydroxypropionate (PAcHP was synthesized by base-catalyzed hydrogen transfer polymerization of acrylic acid through one step. The copolymers obtained through solution and bulk polymerization were insoluble in water and all organic solvents tried. Structural and compositional characterizations of hyperbranched PAcHP were performed by using FTIR, solid 13C-NMR, TGA, and titrimetric analysis. Acrylate fraction of the hyperbranched PAcHP obtained via bulk polymerization was determined as 60–65% by comparing TGA curves of hyperbranched PAcHP and pure poly(3-hydroxy propionate (PHP. However, analytical titration of the same sample revealed that acrylic acid units were about 47.3%. The results obtained from TGA and analytical titration were used to evaluate the chemical structure of the copolymer. Hyperbranched PAcHP exhibited hydrogel properties. Swelling behavior of the copolymer was investigated at a wide pH range and ionic strength. The dynamic swelling profiles of hyperbranched PAcHP exhibited a fast swelling behavior in the first hour and achieved the equilibrium state within 12 h in PBS. Depending on the conditions, the copolymers exhibited swelling ratios up to 2100%. As the copolymer has easily biodegradable propionate and versatile functional acrylic acid units, it can be used as not only biodegradable material in medical applications but also raw material in personal care commodities.

  1. Radiation synthesis of superabsorbent poly(acrylic acid)-carrageenan hydrogels

    Energy Technology Data Exchange (ETDEWEB)

    Francis, Sanju; Kumar, Manmohan; Varshney, Lalit E-mail: lalitv@magnum.barc.ernet.in

    2004-04-01

    A series of superabsorbent hydrogels were prepared from carrageenan and partially neutralized acrylic acid by gamma irradiation at room temperature. The gel fraction, swelling kinetics and the equilibrium degree of swelling (EDS) of the hydrogels were studied. It was found that the incorporation of even 1% carrageenan (sodium salt) increases the EDS of the hydrogels from {approx}320 to {approx}800 g/g. Thermal analysis were carried out to determine the amount of free water and bound water in the hydrogels. Under optimum conditions, poly(acrylic acid)-carrageenan hydrogels with high gel fraction ({approx}80%) and very high EDS ({approx}800 g/g) were prepared gamma radiolytically from aqueous solution containing 15% partially neutralized acrylic acid and 1-5% carrageenan. The hydrogels were also found to be sensitive to the pH and the ionic strength of the medium.

  2. Preparation and characteristics of acrylic acid/styrene composite plasma polymerized membranes

    International Nuclear Information System (INIS)

    Plasma polymerization has gained increasing interest for the deposition of functional plasma-polymerized membranes suitable for a wide range of applications on account of its advantageous features. In this work, acrylic acid/styrene composite plasma polymerized membranes were synthesized by plasma polymerization of a mixture of acrylic acid and styrene monomers in a low-frequency after-glow capacitively coupled plasma (CCP) discharge process. The structure and composition of the plasma polymerized membranes were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results showed that the partial pressure ratio between acrylic acid (AA) and styrene (St), applied discharge power and the energy of the extracted particles have considerable effects on the structure and the content of functional groups of the deposited membranes.

  3. Effects of gas atmospheres on poly(lactic acid) film in acrylic acid plasma treatment

    Science.gov (United States)

    Zhao, Yun; Fina, Alberto; Venturello, Alberto; Geobaldo, Francesco

    2013-10-01

    Plasma polymerized acrylic acid (AA) coatings were deposited on poly(lactic acid) (PLA) films in various gas atmospheres during the pre-treatment of PLA and the deposition of AA, respectively. Therefore, this work was twofold: the argon pretreated PLA films followed by a deposition in argon were investigated against the mixture of argon and oxygen pretreated ones under the same deposition conditions; the plasma deposition of AA operating in different atmospheres (argon, oxygen and nitrogen) was employed to modify the pretreated PLA in oxygen. Chemical and physical changes on the plasma-treated surfaces were examined using contact angle, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and attenuated total reflection infrared (ATR-FTIR) analysis. The results showed that the discharge gas can have a significant influence on the chemical composition of the PLA surfaces: oxygen plasmas introduced oxygen-containing groups in company with surface etching in pretreatment and deposition, while argon discharges was able to achieve much better hydrophilic behavior and high retention ratio of poly(acrylic acid) (PAA) coating before and after washing in water.

  4. Effects of gas atmospheres on poly(lactic acid) film in acrylic acid plasma treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yun, E-mail: yun.zhaotju@yahoo.com [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy); Fina, Alberto [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino – sede di Alessandria, V. T. Michel 5, 15121 Alessandria (Italy); Venturello, Alberto; Geobaldo, Francesco [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy)

    2013-10-15

    Plasma polymerized acrylic acid (AA) coatings were deposited on poly(lactic acid) (PLA) films in various gas atmospheres during the pre-treatment of PLA and the deposition of AA, respectively. Therefore, this work was twofold: the argon pretreated PLA films followed by a deposition in argon were investigated against the mixture of argon and oxygen pretreated ones under the same deposition conditions; the plasma deposition of AA operating in different atmospheres (argon, oxygen and nitrogen) was employed to modify the pretreated PLA in oxygen. Chemical and physical changes on the plasma-treated surfaces were examined using contact angle, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and attenuated total reflection infrared (ATR-FTIR) analysis. The results showed that the discharge gas can have a significant influence on the chemical composition of the PLA surfaces: oxygen plasmas introduced oxygen-containing groups in company with surface etching in pretreatment and deposition, while argon discharges was able to achieve much better hydrophilic behavior and high retention ratio of poly(acrylic acid) (PAA) coating before and after washing in water.

  5. Synthesis and characterization of poly acrylic acid/graphite oxide nanocomposite

    Institute of Scientific and Technical Information of China (English)

    胡源; 丁溶芳; 徐加艳; 王清安; 陈祖耀; 范维澄

    2003-01-01

    Acrylic acid-intercalated graphite oxide and poly acrylic acid (PAA)-intercalated graphite oxide were prepared and characterized by X-Ray diffraction (XRD), Fourier transform infrared spectra (FTIR) and high resolution electronic microscope (HREM). Results show that the intercalation process is not only a physical diffusion process but also mainly a chemical reaction process. The high resolution electronic microscope results also reveal that the Ic value of PAA-intercalated graphite oxide (GO) could change widely from 1.6nm to 4.0nm.

  6. The influence of Copolimers Acrylic Acid onto Poli(Etilene Terephthalate)woven fabric

    International Nuclear Information System (INIS)

    To improve suitability of wearing poli etilene terephthalate (PET) wovenfabric, it need to enhance the ability in absorbing of water vapour. For theabove reason acrylic acid (AA) has been grafted onto PET wovenfabric(PET-g-AA). Fourier Transform Infrared (FT-IR) data show that poly(acrylic acid) have grafted onto PET woven fabric. Thermal propertiesobtained from DSC (Differential Scanning Calorimeter) measurements of PET-g-AA show that the grafting does not affect bulk properties of PET. Thedecrease of the tensile strength had occurred to PET-g-MMA, however it ratherinfluenced by the reaction time than the initial concentration of acrylicacid. (author)

  7. Synthesis of Acrylic Acid/Kaoline Powder Superabsorbent Composite by Inverse-suspending Polymerization

    Institute of Scientific and Technical Information of China (English)

    ZHONG Jin-feng; XUE Yi-ming; WU Ji-huai; LIN Jian-ming; WEI Yue-lin

    2004-01-01

    An acrylic acid/kaoline powder superabsorbent composite with a water absorbency of the superabsorbent composite about 1/800 was synthesized by inverse-suspending polymerization reaction between acrylic acid monomer and kaoline ultrafine powder. The influence of the dispersant agent on the configuration of the products in the inverse suspension polymerization is investigated. The influences of the kaoline powder, cross-linker, initiator, neutralization degree and the volume ratio of oil to water phase on the water absorbency of the superabsorbent composites are discussed in the paper.

  8. Graft Copolymerization of Acrylic Acid onto Fungal Cell Wall Structural Polysaccharide

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Acrylic acid was graft-copolymerized onto Rhi. oryzae's cell wall structural polysacchaxide directly and efficiently in aqueous solution with ceric ammonium nitrate as initiator. The maximal grafting percentage of 135.5% was obtained under the condition of [Ce4+]=5mmol.L-1, [AA]=1mol.L-1, T=60°C and t=3h. Graft copolymerization was suggested to proceed through free radical reaction mechanism. Grafting occurred primarily on chitosan. Acrylic acid was also attempted to be grafted onto Asp. niger cell wall structural polysaccharide, and only 44.2% of grafting percentage was resulted.

  9. Electroactive behavior assessment of poly(acrylic acid)-graphene oxide composite hydrogel in the detection of cadmium

    NARCIS (Netherlands)

    Bejarano-Jimenez, A.; Escobar-Barrios, V.A.; Kleijn, J.M.; Oritz-Ledon, C.A.; Chazaro-Ruiz, L.F.

    2014-01-01

    Super absorbent polymers of acrylic acid-graphene oxide (PAA-GO) were synthesized with different percentage of chemical neutralization (0, 10, and 20%) of the acrylic acid monomer before its polymerization. The influence of their swelling and adsorption/desorption capacity of cadmium ions in aqueous

  10. SYNTHESIS OF 2—HYDROXYETHYL ACRYLATE BY USING STRONG ACIDIC CATION ION EXCHANGE RESIN AS CATALYST

    Institute of Scientific and Technical Information of China (English)

    GAODabin

    1992-01-01

    2-Hydroxyethyl acrylate is synthesized from acrylic acid and ethylene glycol under a simple and mild condition by using strong acidic cation ion exchange resin as a catalyst,which could be recycled as long as 10 times with high activation.

  11. Poly(acrylic acid) to induce competitive crystallization of a theophylline/oxalic acid cocrystal and a theophylline polymorph

    Science.gov (United States)

    Jang, Jisun; Kim, Il Won

    2016-01-01

    Polymeric additives to induce competitive crystallization of pharmaceutical compounds were explored. A cocrystal of theophylline and oxalic acid was used as a model system, and poly(acrylic acid), poly(caprolactone), and poly(ethylene glycol) were the additives. The cocrystal formation was selectively hindered with addition of poly(acrylic acid). First the size of the cocrystals were reduced, and eventually the cocrystallization was inhibited to generate neat theophylline crystals. The theophylline crystals were of a distinctively different crystal structure from known polymorphs, based on powder X-ray diffraction. They were also obtained in nanoscale size, when millimeter-scale crystals formed without poly(acrylic acid). Polymeric additives that could form specific interactions with crystallizing compounds seem to be useful tools for the phase and size control of pharmaceutical crystals.

  12. Gold Nanoparticles Protected with Thiol-Derivatized Amphiphilic Poly(epsilon-caprolactone)-b-poly(acrylic acid)

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Hvilsted, Søren

    2009-01-01

    Amphiphilic poly(epsilon-caprolactone)-b-poly(acrylic acid) (HS-PCL-b-PAA) with a thiol functionality in the PCL terminal has been prepared in a novel synthetic cascade. Initially, living anionic ring-opening polymerization (ROP) of epsilon-caprolactone (epsilon-CL) employing the difunctional...

  13. Selective oxidation of propane to acrylic acid over mixed metal oxide catalysts

    Institute of Scientific and Technical Information of China (English)

    Wei Zheng; Zhenxing Yu; Ping Zhang; Yuhang Zhang; Hongying Fu; Xiaoli Zhang; Qiquan Sun; Xinguo Hu

    2008-01-01

    The effects of metal atomic ratio, water content, oxygen content, and calcination temperature on the catalytic perfor-mances of MoVTeNbO mixed oxide catalyst system for the selective oxidation of propane to acrylic acid have been investigated and discussed. Among the catalysts studied, it was found that the MoVTeNbO catalyst calcined at a temperature of 600 ℃ showed the best performance in terms of propane conversion and selectivity for acrylic acid under an atmosphere of nitrogen. An effective MoVTeNbO oxide catalyst for propane selective oxidation to acrylic acid was obtained with a combination of a preferred metal atomic ratio (Mo1 V0.31Te0.23Nb0.12). The optimum reaction condition for the selective oxidation of propane was the molar ratio of C3H81 :O2 : H2O : N1 = 4.4 : 12.8 : 15.3 : 36.9. Under such conditions, the conversion of propane and the maximum yield of acrylic acid reached about 50% and 21%, respectively.

  14. Monitor of Polymerization of Inverse Microemulsions Containing Methyl Methacrylate and Acrylic Acid

    Institute of Scientific and Technical Information of China (English)

    Xiao LI; Sheng Ping XIA; Wei Jie ZENG; Wei Ying ZHANG; Sheng Xiong DONG

    2006-01-01

    The polymerization of the inverse microemulsions composed of methyl methacrylate,acrylic acid, sodium dodecyl sulfate and water was monitored by refractometer, conductometer and time-resolved light scattering device. The results showed that refractive index, conductivity or intensity distribution of scattered light changed along with polymerization, and different processes of polymerization could be identified.

  15. Radioluminescence of polyester resin modified with acrylic acid and its salts

    Science.gov (United States)

    Szalińska, H.; Wypych, M.; Pietrzak, M.; Szadkowska-Nicze, M.

    Polimal-109 polyester resin and its compounds containing acrylic acid and its salts such as: sodium, potassium, magnesium, calcium, barium, iron, cobalt, copper and manganese acrylates were studied by the radioluminescence method, including isothermal luminescence (ITL) at a radiation temperature of 77 K, thermoluminescence (RTL) and spectral distributions of isothermal luminescence. Measurements of optical absorption at 77 K before and after irradiation of the investigated samples were also carried out. The results obtained have shown that metal ions play a significant part in the processes taking place in the polyester matrix under the influence of γ 60Co radiation.

  16. Cisplatin-incorporated nanoparticles of poly(acrylic acid-co-methyl methacrylate copolymer

    Directory of Open Access Journals (Sweden)

    Lee KD

    2013-08-01

    Full Text Available Kyung Dong Lee,1,* Young-Il Jeong,2,* Da Hye Kim,3,4 Gyun-Taek Lim,2 Ki-Choon Choi5 1Department of Oriental Medicine Materials, Dongshin University, Naju, South Korea; 2Department of Polymer Engineering, Chonnam National University, Gwangju, South Korea; 3Faculty of Life and Environmental Science, Shimane University, Matsue, Japan; 4United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan; 5Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan, South Korea *These authors contributed equally to this work Background: Although cisplatin is extensively used in the clinical field, its intrinsic toxicity limits its clinical use. We investigated nanoparticle formations of poly(acrylic acid-co-methyl methacrylate (PAA-MMA incorporating cisplatin and their antitumor activity in vitro and in vivo. Methods: Cisplatin-incorporated nanoparticles were prepared through the ion-complex formation between acrylic acid and cisplatin. The anticancer activity of cisplatin-incorporated nanoparticles was assessed with CT26 colorectal carcinoma cells. Results: Cisplatin-incorporated nanoparticles have small particle sizes of less than 200 nm with spherical shapes. Drug content was increased according to the increase of the feeding amount of cisplatin and acrylic acid content in the copolymer. The higher acrylic acid content in the copolymer induced increase of particle size and decrease of zeta potential. Cisplatin-incorporated nanoparticles showed a similar growth-inhibitory effect against CT26 tumor cells in vitro. However, cisplatin-incorporated nanoparticles showed improved antitumor activity against an animal tumor xenograft model. Conclusion: We suggest that PAA-MMA nanoparticles incorporating cisplatin are promising carriers for an antitumor drug-delivery system. Keywords: cisplatin, nanoparticle, poly(acrylic acid-co-methyl methacrylate, ion complexes

  17. Adsorption of uranium ions by crosslinked polyester resin functionalized with acrylic acid from aqueous solutions

    International Nuclear Information System (INIS)

    In this paper, the crosslinked polyester resin containing acrylic acid functional groups was used for the adsorption of uranium ions from aqueous solutions. For this purpose, the crosslinked polyester resin of unsaturated polyester in styrene monomer (Polipol 353, Poliya) and acrylic acid as weight percentage at 80 and 20%, respectively was synthesized by using methyl ethyl ketone peroxide (MEKp, Butanox M60, Azo Nobel)-cobalt octoate initiator system. The adsorption of uranium ions on the sample (0.05 g copolymer and 5 mL of U(VI) solution were mixed) of the crosslinked polyester resin functionalized with acrylic acid was carried out in a batch reactor. The effects of adsorption parameters of the contact time, temperature, pH of solution and initial uranium(VI) concentration for U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid were investigated. The adsorption data obtained from experimental results depending on the initial U(VI) concentration were analyzed by the Freundlich, Langmuir and Dubinin-Radushkevich (D-R) adsorption isotherms. The adsorption capacity and free energy change were determined by using D-R isotherm. The obtained experimental adsorption data depending on temperature were evaluated to calculate the thermodynamic parameters of enthalpy (ΔHo), entropy (ΔSo) and free energy change (ΔGo) for the U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid from aqueous solutions. The obtained adsorption data depending on contact time were analyzed by using adsorption models such as the modified Freundlich, Elovich, pseudo-first order and pseudo-second-order kinetic models. (author)

  18. GROUP TRANSFER POLYMERIZATION OF ETHYL ACRYLATE WITH LEWIS ACID CATALYST

    Institute of Scientific and Technical Information of China (English)

    XU Linyun; Wang Lei

    1989-01-01

    This paper reports the kinetics of group transfer polymerization (GTP) of ethyl acrylate (EA) with zinc iodide catalyst in 1,2- dichloroethane using dimethyl ketene methyl trimethylsilyl acetal ( MTS ) as initiator at 0 ℃ and above 0 ℃ . The amount of catalyst used was studied. When zinc iodide catalyst used is more than 10mol% relative to monomer, the rate of polymerization is proportional to the concentration of monomer, whereas zinc iodide catalyst used is less than 10 mol% of the monomer, the rate of polymerization is independent of the monomer concentration. In the GTP of EA an induction period was observed when the zinc iodide contents are less than 10 mol%. If the reaction temperature is over 0 ℃ , living species become unstable and diminish, leading to incomplete monomer conversion. The reaction curves equations are obtained. The polymers have narrow molecular weight distributions which are not changed as decreasing zinc iodide contents. The polydispersity is about 1.2.

  19. CHARACTERIZATION OF RADIATION GRAFTING DEGREE OF POLYSTYRENE g-ACRYLIC ACID BY XPS

    Institute of Scientific and Technical Information of China (English)

    CHE Jitai; ZHANG Wanxi

    1990-01-01

    It this work, characterization of radiation grafting degree of polystyrene-g-acrylic acid by XPS was studied. It is found that along with the main peak C1s there is a photoelectron peak at 289.0 eV that appears to be C1s of -C(=O)-OH group and shows the presence ofpolyacrylic acid grafted on the polystyrene.The grafting degree obtained by XPS is in agreement with that from the gravimetric method.

  20. Pre-irradiation induced emulsion co-graft polymerization of acrylonitrile and acrylic acid onto a polyethylene nonwoven fabric

    Science.gov (United States)

    Liu, Hanzhou; Yu, Ming; Ma, Hongjuan; Wang, Ziqiang; Li, Linfan; Li, Jingye

    2014-01-01

    A pre-irradiation induced emulsion co-graft polymerization method was used to introduce acrylonitrile and acrylic acid onto a PE nonwoven fabric. The use of acrylic acid is meant to improve the hydrophilicity of the modified fabric. The kinetics of co-graft polymerization were studied. The existence of polyacrylonitrile (PAN) and poly(acrylic acid) (PAAc) graft chains was proven by Fourier transform infrared spectroscopy (FTIR) analysis. The existence of the nitrile groups in the graft chains indicates that they are ready for further amidoximation and adsorption of heavy metal ions.

  1. Separation of water and oil by poly (acrylic acid)-coated stainless steel mesh prepared by radiation crosslinking

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young Chang; Shin, Jung Woong; Park, Jong Seok; Lim, Young Mook; Jeun, Joon Pyo; Kang, Phil Hyun [Research Division for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2015-05-15

    The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

  2. Dehydration of lactic acid to acrylic acid over lanthanum phosphate catalysts: the role of Lewis acid sites.

    Science.gov (United States)

    Guo, Zhen; Theng, De Sheng; Tang, Karen Yuanting; Zhang, Lili; Huang, Lin; Borgna, Armando; Wang, Chuan

    2016-09-14

    Lanthanum phosphate (LaP) nano-rods were synthesized using n-butylamine as a shape-directing agent (SDA). The resulting catalysts were applied in the dehydration of lactic acid to acrylic acid. Aiming to understand the nature of the active sites, the chemical and physical properties of LaP materials were studied using a variety of characterization techniques. This study showed that the SDA not only affected the porosity of the LaP materials but also modified the acid-base properties. Clearly, the modification of the acid-base properties played a more critical role in determining the catalytic performance than porosity. An optimized catalytic performance was obtained on the LaP catalyst with a higher concentration of Lewis acid sites. Basic sites showed negative effects on the stability of the catalysts. Good stability was achieved when the catalyst was prepared using the appropriate SDA/La ratio.

  3. Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

    International Nuclear Information System (INIS)

    The oxidative dehydration of glycerol to acrylic acid was studied over vanadium-impregnated zeolite Beta. Catalysts were prepared by wet impregnation of ammonium metavanadate over ammonium-exchanged zeolite Beta, followed by air calcination at 823 K. Impregnation reduced the specific surface area, but did not significantly affected the acidity (Bronsted and Lewis) of the zeolites. The catalytic evaluation was carried out in a fixed bed flow reactor using air as the carrier and injecting glycerol by means of a syringe pump. Acrolein was the main product, with acetaldehyde and hydroxy-acetone (acetol) being also formed. Acrylic acid was formed with approximately 25% selectivity at 548 K over the impregnated zeolites. The result can be explained by XPS (X-ray photoelectron spectroscopy) measurements, which indicated a good dispersion of the vanadium inside the pores. (author)

  4. Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

    Energy Technology Data Exchange (ETDEWEB)

    Pestana, Carolina F.M.; Guerra, Antonio C.O.; Turci, Cassia C. [Universidade Federal do Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Ferreira, Glaucio B. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Quimica; Mota, Claudio J.A., E-mail: cmota@iq.ufrj.br [INCT Energia e Ambiente, Universidade Federal do Rio de Janeiro, RJ (Brazil)

    2013-01-15

    The oxidative dehydration of glycerol to acrylic acid was studied over vanadium-impregnated zeolite Beta. Catalysts were prepared by wet impregnation of ammonium metavanadate over ammonium-exchanged zeolite Beta, followed by air calcination at 823 K. Impregnation reduced the specific surface area, but did not significantly affected the acidity (Bronsted and Lewis) of the zeolites. The catalytic evaluation was carried out in a fixed bed flow reactor using air as the carrier and injecting glycerol by means of a syringe pump. Acrolein was the main product, with acetaldehyde and hydroxy-acetone (acetol) being also formed. Acrylic acid was formed with approximately 25% selectivity at 548 K over the impregnated zeolites. The result can be explained by XPS (X-ray photoelectron spectroscopy) measurements, which indicated a good dispersion of the vanadium inside the pores. (author)

  5. Superabsorbent biphasic system based on poly(lactic acid) and poly(acrylic acid)

    Science.gov (United States)

    Sartore, Luciana; Pandini, Stefano; Baldi, Francesco; Bignotti, Fabio

    2016-05-01

    In this research work, biocomposites based on crosslinked particles of poly(acrylic acid), commonly used as superabsorbent polymer (SAP), and poly-L-lactic acid (PLLA) were developed to elucidate the role of the filler (i.e., polymeric crosslinked particles) on the overall physico-mechanical behavior and to obtain superabsorbent thermoplastic products. Samples prepared by melt-blending of components in different ratios showed a biphasic system with a regular distribution of particles, with diameter ranging from 5 to 10 μm, within the PLLA polymeric matrix. The polymeric biphasic system, coded PLASA i.e. superabsorbent poly(lactic acid), showed excellent swelling properties, demonstrating that cross-linked particles retain their superabsorbent ability, as in their free counterparts, even if distributed in a thermoplastic polymeric matrix. The thermal characteristics of the biocomposites evidence enhanced thermal stability in comparison with neat PLLA and also mechanical properties are markedly modified by addition of crosslinked particles which induce regular stiffening effect. Furthermore, in aqueous environments the particles swell and are leached from PLLA matrix generating very high porosity. These new open-pore PLLA foams, produced in absence of organic solvents and chemical foaming agents, with good physico-mechanical properties appear very promising for several applications, for instance in tissue engineering for scaffold production.

  6. Determination of acrylamide and acrylic acid by isocratic liquid chromatography with pulsed electrochemical detection.

    Science.gov (United States)

    Casella, Innocenzo G; Pierri, Marianna; Contursi, Michela

    2006-02-24

    The electrochemical behaviour of the polycrystalline platinum electrode towards the oxidation/reduction of short-chain unsaturated aliphatic molecules such as acrylamide and acrylic acid was investigated in acidic solutions. Analytes were separated by reverse phase liquid chromatographic and quantified using a pulsed amperometric detection. A new two-step waveform, is introduced for detection of acrylamide and acrylic acid. Detection limits (LOD) of 20 nM (1. 4 microg/kg) and 45 nM (3.2 microg/kg) were determined in water solutions containing acrylamide and acrylic acid, respectively. Compared to the classical three-step waveform, the proposed two-step waveform shows favourable analytical performance in terms of LOD, linear range, precision and improved long-term reproducibility. The proposed analytical method combined with clean-up procedure accomplished by Carrez clearing reagent and subsequent extraction with a strong cation exchanger cartridges (SPE), was successfully used for the quantification of low concentrations of acrylamide in foodstuffs such as coffee and potato fries. PMID:16426623

  7. Hierarchically organized architecture of potassium hydrogen phthalate and poly(acrylic acid): toward a general strategy for biomimetic crystal design.

    Science.gov (United States)

    Oaki, Yuya; Imai, Hiroaki

    2005-12-28

    A hierarchically organized architecture in multiple scales was generated from potassium hydrogen phthalate crystals and poly(acrylic acid) based on our novel biomimetic approach with an exquisite association of polymers on crystallization. PMID:16333511

  8. Preparation and evaluation of chitosan-poly (acrylic acid hydrogels as stomach specific delivery for amoxicillin and metronidazole

    Directory of Open Access Journals (Sweden)

    Hemant Yadav K

    2007-01-01

    Full Text Available The objective of the present work was to develop stomach specific delivery systems for amoxicillin and metronidazole using chitosan and poly(acrylic acid hydrogels. Chitosan and poly(acrylic acid hydrogels were prepared with different composition of copolymers. The hydrogels were evaluated for swelling studies, mucoadhesive studies, in vitro drug release, scanning electron microscopic and FTIR analysis. The effect of chitosan and poly (acrylic acid on swelling and in vitro drug release was carried out. The n value calculated was < 0.5 for all the formulations containing amoxicillin and metronidazole indicating Fickian diffusion mechanism. The hydrogels with chitosan and poly (acrylic acid ratio of 0.25:1 showed greater mucoadhesive property, maximum swelling and complete release of drugs, hence can be used for stomach specific delivery of drugs.

  9. Removal of Dyes from Aqueous Solutions Using Radiation Synthesized (2-Hydroxyethyl Methacrylate/Acrylic acid) Hydrogels

    International Nuclear Information System (INIS)

    Acrylic acid/2-hydroxyethyl methacrylate super absorbent hydrogels (AAc/ HEMA) were prepared by γ-radiation copolymerization of 2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AAc). Characterization of AAc/HEMA hydrogel was done by FTIR, TGA, SEM and XRD. The swelling properties were studied as a function of time, ph and irradiation dose. The diffusion behavior of water into these hydrogels followed the Fickian character at all investigated irradiation doses. The adsorption of Direct Congo Red and Direct Blue dyes onto the AAc/ HEMA hydrogel was studied. Physico-chemical parameters like dye concentration, solution ph and temperature were varied to characterize the adsorption phenomenon. Experimental data were modeled by Freundlich isotherm. Thermodynamic parameters ( ΔHo, ΔGo and ΔSo ) were evaluated for the dyes adsorbent systems, which suggest that the adsorption process is a typical physical process and endothermic in nature

  10. Preparation of poly (acrylic acid)-modified chitosan amphiphilic gels by γ-rays irradiation

    International Nuclear Information System (INIS)

    Poly (acrylic acid)-modified chitosan amphiphilic gels were prepared via O-maleoyl-N-phthaloyl- chitosan as an intermediate by grafting with poly (acrylic acid). The reaction was carried out in a homogeneous sys- tem by γ-ray irradiation. Evidence of grafting was obtained from FTIR spectroscopy. The effects for grafting reaction were investigated systematically. Results show that the grafting degree depends on monomer concentration and ab- sorbed dose. The swelling behavior of chitosan samples with different grafting degree was studied in different buffers as a function of pH. It can be found that all the samples swollen slightly at low pH but very well at high pH. More- over, the swelling behavior of chitosan samples in DMF has been evaluated. (authors)

  11. Super absorbent Prepared by Radiation Induced Graft Copolymerization of Acrylic Acid onto Cassava Starch

    International Nuclear Information System (INIS)

    Full text: Super absorbent was synthesized by radiation-induced graft polymerization of acrylic acid onto cassava starch. Parameters such as the absorbed dose and the amount of monomer were investigated in order to determine the optimum conditions for the grafting polymerization. Water retention, germination percentage and germination energy were determined in order to evaluate the possibility of super absorbent in agricultural applications, especially in arid regions. The graft copolymer was characterized by FTIR. Results indicated that the sand mixed with 0.1%wt super absorbent can absorb more water than the sand without super absorbent. The germination energy of corn seeds mixed with 0.5% super absorbent was obviously higher than those without super absorbent. These experimental results showed that the super absorbent has considerable effect on seed germination and the growth of young plants. Keywords: Super absorbent, Radiation, Acrylic acid, Cassava starch

  12. Flocculation Efficiency of Poly(Acrylamide-Co-Acrylic Acid) Obtained by Electron Beam Irradiation

    OpenAIRE

    Gabriela Craciun; Elena Manaila; Maria-Daniela Stelescu

    2013-01-01

    A correlation between physicochemical characteristics of flocculants obtained by electron beam irradiation and their efficiency for wastewater treatment is presented. For real wastewater treatment, our interest was focused upon total suspended solids, fatty matter, and chemical oxygen demand. Flocculation studies were carried out using a standard jar test. A treatment option based on poly(acrylamide-co-acrylic acid) for wastewater taken from a slaughterhouse plant is presented.

  13. Investigation on the Inverse Emulsion Polymerization of Acrylic Acid

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Polyacrylic acid particles in nano-scale were synthesized using an inverse (W/O) emulsion polymerization method. The particle size and size change of inverse micelles which solubilize a part of monomer solution was monitored by PCS (photon correlation spectroscopy) and the particles of polyacrylic acid were viewed in scanning electron microscope for the first time. It was concluded that the inverse micelles were primarily the polymerization reaction sites.

  14. Synthesis and characterization of kappaphycus seaweed-poly (acrylic) acid superabsorbent hydrogel for agricultural use

    International Nuclear Information System (INIS)

    The main objective of this research is to synthesize and characterize kappaphycus seaweed-poly (acrylic) acid superabsorbent hydrogel for agricultural use. The superabsorbent polymers (SAPs), KCSW: PAA hydrogels were synthesized by using gamma radiation technique from Cobalt-60 source at absorbed dose 0f 5, 10 and 15 kGy. The effect of absorbed dose, seaweed concentration, and concentration of acrylic acid on the degree of swelling was studied and optimum swelling conditions were established. Irradiated samples of 3% KCSW, 50% neutralized AAC at an absorbed dose of 10kGy gave the highest degree of swelling and gel fraction and were found to be suitable for application in the agriculture. Samples with different concentrations of acrylic acid were characterized using FTIR and TGA. The water retention experiment in sandy soil showed high water retention capacity of KCSW: PAA hydrogel at a value of 92% for a period of 7 days. Effect of the germination of mung bean showed very promising result of 78% germination.(author)

  15. Acrylic acid polymerization and its graft copolymerization to poly(ethylene oxide) by gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Hochberg, A.

    1984-01-01

    Free radical initiated polymerization of acrylic acid was investigated in methanol-water solutions with and without poly(ethylene oxide) (PEO). The formation of poly(acrylic acid) (PAA) initiated both by gamma irradiation and water soluble azo initiators was found to follow classical free radical kinetics. A significant increase in the rate of the propagation step (together with the degree of polymerization) was observed as the water fraction of the medium increased. During homogeneous polymerization of acrylic acid in methanol-water solutions containing poly(ethylene oxide), PAA grafting efficiency was found to be 67% and independent of initiation rate and yield. A mechanism of grafting to poly(ethylene oxide) was proposed. Chain transfer to PEO (K/sub tr/ = 6.5 x 10/sup -5/) was found to be the dominant mechanism for graft formation. Drag reduction characteristics of these PEO-PAA graft copolymers were measured in dilute aqueous solutions as a function of Reynolds number and solution pH. PEO graft copolymers containing 45% by mole PAA graft had, in neutral and basic solutions, drag reduction characteristics equivalent on a mass basis to the initial PEO. However at low pH, drag reduction characteristics disappeared as the PEO-PAA coacervate formed.

  16. Preparation and characterization of poly(acrylic acid)-hydroxyethyl cellulose graft copolymer.

    Science.gov (United States)

    Abdel-Halim, E S

    2012-10-01

    Poly(acrylic acid) hydroxyethyl cellulose [poly(AA)-HEC] graft copolymer was prepared by polymerizing acrylic acid (AA) with hydroxyethyl cellulose (HEC) using potassium bromate/thiourea dioxide (KBrO(3)/TUD) as redox initiation system. The polymerization reaction was carried out under a variety of conditions including concentrations of AA, KBrO(3) and TUD, material to liquor ratio and polymerization temperature. The polymerization reaction was monitored by withdrawing samples from the reaction medium and measuring the total conversion. The rheological properties of the poly(AA)-HEC graft copolymer were investigated. The total conversion and rheological properties of the graft copolymer depended on the ratio of KBrO(3) to TUD and on acrylic acid concentration as well as temperature and material to liquor ratio. Optimum conditions of the graft copolymer preparation were 30 mmol KBrO(3) and 30 mmol TUD/100g HEC, 100% AA (based on weight of HEC), duration 2h at temperature 50 °C using a material to liquor ratio of 1:10. PMID:22840022

  17. Influence of ozone and paracetic acid disinfection on adhesion of resilient liners to acrylic resin

    Science.gov (United States)

    2016-01-01

    PURPOSE The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. MATERIALS AND METHODS One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. RESULTS Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. CONCLUSION The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials. PMID:27555898

  18. Phase Transition of Poly(acrylic acid-co-N-isopropylacrylamide) Core-shell Nanogels

    Science.gov (United States)

    Liu, Xiao-bing; Zhou, Jian-feng; Ye, Xiao-dong

    2012-08-01

    A series of poly(acrylic acid) macromolecular chain transfer agents with different molecular weights were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and characterized by 1H NMR and gel permeation chromatography. Multiresponsive core-shell nanogels were prepared by dispersion polymerization of N-isopropylacrylamide in water using these poly(potassium acrylate) macro-RAFT agents as the electrosteric stabilizer. The size of the nanogels decreases with the amount of the macro-RAFT agent, indicating that the surface area occupied by per polyelectrolyte group is a critical parameter for stabilizing the nanogels. The volume phase transition and the zeta potentials of the nanogels in aqueous solutions were studied by dynamic light scattering and zetasizer analyzer, respectively.

  19. ESTERIFICATION OF ACRYLIC ACID WITH 1-BUTANOL IN LIQUID PHASE CATALYZED WITH AL-MCM-41

    OpenAIRE

    Edson Avellaneda Maytán; Gustavo Paim Valença

    2010-01-01

    This work studies the esterification of acrylic acid with 1-butanol using Al-MCM-41 as catalyst with different degrees of acidity at different temperatures. Al-MCM-41 synthesis was made from bromate Cetyl trimethyl ammonium using as router agent, NH4OH (25%), deionized H2O and Al2(SO4)3. Catalytic tests were carried out by groups and worked with temperature ranges among (333 to 348) K and a small sample was collected at predetermined intervals of time for subsequent gas chromatography analysi...

  20. Ultra-Thin Films of Poly(acrylic acid)/Silver Nanocomposite Coatings for Antimicrobial Applications

    OpenAIRE

    Alaa Fahmy; Eisa, Wael H.; Mohamed Yosef; Ali Hassan

    2016-01-01

    In this work not only colloids of poly(acrylic acid) (PAA) embedded with silver nanoparticles (Ag-NPs) but thin films (10 nm) also were deposited using electrospray deposition technique (ESD). A mixture of sodium borohydride (NaBH4) and ascorbic acid (AA) were utilized to reduce the silver ions to generate Ag-NPs in the PAA matrix. Moreover, sodium tricitrate was used to stabilize the prepared colloids. The obtained colloids and films were characterized using UV-visible, transmission electron...

  1. Salicylic acid-releasing polyurethane acrylate polymers as anti-biofilm urological catheter coatings.

    Science.gov (United States)

    Nowatzki, Paul J; Koepsel, Richard R; Stoodley, Paul; Min, Ke; Harper, Alan; Murata, Hironobu; Donfack, Joseph; Hortelano, Edwin R; Ehrlich, Garth D; Russell, Alan J

    2012-05-01

    Biofilm-associated infections are a major complication of implanted and indwelling medical devices like urological and venous catheters. They commonly persist even in the presence of an oral or intravenous antibiotic regimen, often resulting in chronic illness. We have developed a new approach to inhibiting biofilm growth on synthetic materials through controlled release of salicylic acid from a polymeric coating. Herein we report the synthesis and testing of a ultraviolet-cured polyurethane acrylate polymer composed, in part, of salicyl acrylate, which hydrolyzes upon exposure to aqueous conditions, releasing salicylic acid while leaving the polymer backbone intact. The salicylic acid release rate was tuned by adjusting the polymer composition. Anti-biofilm performance of the coatings was assessed under several biofilm forming conditions using a novel combination of the MBEC Assay™ biofilm multi-peg growth system and bioluminescence monitoring for live cell quantification. Films of the salicylic acid-releasing polymers were found to inhibit biofilm formation, as shown by bioluminescent and GFP reporter strains of Pseudomonas aeruginosa and Escherichia coli. Urinary catheters coated on their inner lumens with the salicylic acid-releasing polymer significantly reduced biofilm formation by E. coli for up to 5 days under conditions that simulated physiological urine flow.

  2. Synthesis of acrylic prepolymer

    International Nuclear Information System (INIS)

    An acrylic prepolymer was synthesized from glycidyl methacrylate (GMA), butyl methacrylate (BMA), methyl methacrylate (MMA) and acrylic acid (AA). Butyl acetate (BAc), benzoyl peroxide (BzO), 4-methoxyphenol (MPh) and triethylamine (TEA) were used as solvent, initiator, inhibitor and catalyst respectively. Observations of the synthesis leading to the formation of acrylic prepolymer are described. (author)

  3. Antibacterial activity of chitosan and the interpolyelectrolyte complexes of poly(acrylic acid-chitosan

    Directory of Open Access Journals (Sweden)

    Hortensia Ortega-Ortiz

    2010-06-01

    Full Text Available The antimicrobial activity of chitosan and water soluble interpolyelectrolyte complexes of poly(acrylic acid-chitosan was studied. Chitosans of two different molecular weights were tested at different concentration for 0.5 to 5 g·L-1 as antimicrobial agents against P. aeruginosa and P. oleovorans. In both cases, the best microbial inhibition was obtained with the concentration of 5 g·L-1. However, the interpolyelectrolyte complexes of poly(acrylic acid-chitosan with composition φ =2 produced higher antibacterial activity than the two chitosans at the concentration of 0.5 g·L-1. The NPEC2 complex was more effective than chitosans. This could be attributed to the number of moles of the amino groups of chitosan and the carboxylic acid groups of the interpolyelectrolyte complexes poly(acrylic acid.A atividade antimicrobiana de quitosana e complexos interpolieletrolíticos hidrossoluvéis de poli(ácido acrílico-quitosana foi estudada. Quitosanas de dois diferentes pesos moleculares foram testados em diferentes concentrações, 0,5 a 5 g • L-1, como agentes antimicrobianos nas P. aeruginosa e P. oleovorans. Em ambos os casos, obteu-se a melhor inibição microbiana com a concentração de 5 g • L-1, no entanto os complexos interpolieletrolíticos de poli (ácido acrílico-quitosana com composição φ = 2 apresentaram maior atividade antibacteriana do que os dois quitosans na concentração de 0,5 g • L-1. O complexo NPEC2 foi mais eficaz do que as quitosanas, sendo que o resultado pode ser atribuído ao número de moles dos grupos aminos da quitosana e aos grupos carboxílicos dos complexos de poli(ácido acrílico.

  4. Synthesis of superabsorbent hydrogel by radiation crosslinking of acrylic acid, semi-refined kappa-carrageenan and sugarcane bagasse blend

    International Nuclear Information System (INIS)

    Superabsorbent hydrogels have three-dimensional networks that enable it to exhibit great water absorption capacity leading to its promising applications. However, existing commercial hydrogels are mainly acrylic acid which causes environmental problems. In this study, the incorporation of agricultural waste as filler and polysaccharide from natural sources as binder for the production of superabsorbent hydrogel was done to reduce the use of acrylic acid as well as its environmental impact while adding value to the incorporated materials. A series of superabsorbent hydrogel with the blend of acrylic acid, semi-refined kappa carrageenan and sugarcane bagasse were synthesized by radiation crosslinking. The gel fraction and swelling capacity of the hydrogels were determined and studied. The characterizations were facilitated by Fourier transform infrared spectroscopy technique (FTIR) and Thermogravimetric Analysis (TGA). In the results obtained from analyses, the characteristic peaks of acrylic acid and sugarcane bagasse were observed in the FTIR spectra and the three step peaks if synthesized hydrogel in its TGA implies an improvement in thermal stability of the product. The synthesized superabsorbent hydrogel blends had exhibited comparable gel fraction to that of the polyacrylic acid hydrogel, had great swelling capacity, and achieved equilibrium degree of swelling within 72-96 hours. The optimum synthesized superabsorbent hydrogel is 3% semi-refined kappa-carrageenan, 3% sugarcane bagasse, 15% acrylic acid neutralize up to 50% and irradiated at 15kGy dose which exhibited a swelling of 599.53 and gel fraction of 39.73. (author)

  5. Physicochemical and electrochemical characterization of battery separator prepared by radiation induced grafting of acrylic acid onto microporous polypropylene membranes

    Directory of Open Access Journals (Sweden)

    2009-05-01

    Full Text Available Mutual radiation grafting technique was used to graft acrylic acid on micrometer thick micro-porous polypropylene membrane using high-energy gamma radiation. Grafting could not be achieved in aqueous acrylic acid solution. The presence of Mohr’s salt effectively retarded the homopolymerization of acrylic acid but did not lead to grafting enhancement. Mohr’s salt in presence of acids was found to be effective in enhancing the grafting yield. Contact angle measurement studies of the grafted and radiation treated polypropylene showed that initial grafting as well as radiation treatment of poly(propylene in aqueous medium and in presence of Mohr’s salt enhances its affinity towards the grafting solution. The enhancement in the polar component of surface energy of treated polypropylene membrane is the primary cause of grafting enhancement. The membranes grafted to an extent of ~20% were found to perform comparably with the battery separator presently being used by battery industry.

  6. Modification of hydrophobic polypeptide-based film by blending with hydrophilic poly(acrylic acid

    Directory of Open Access Journals (Sweden)

    Guoquan Zhu

    2013-01-01

    Full Text Available In this study, a series of poly(γ-benzyl L-glutamate/poly(acrylic acid (PBLG/PAA polymer blend films were prepared by casting the polymer blend solution in dimethylsulfoxide (DMSO. The structure and morphology of the polymer blend film were investigated by Fourier Transform Infrared Spectroscopy (FT-IR and Scanning Electron Microscopy (SEM. Thermal, mechanical, and chemical properties of PBLG/PAA polymer blend films were studied by Differential Scanning Calorimetry (DSC, Thermogravimetric (TG Analysis, Tensile Tests, and measurements of Surface Contact Angles. The results revealed that the introduction of PAA could exert great effects on the structure and properties of the polypeptide films.

  7. Synthesis of poly(N-isopropylacrylamide-co-acrylic acid) model compounds for filtration experiments

    DEFF Research Database (Denmark)

    Hinge, Mogens; Christensen, Morten Lykkegaard; Scales, Peter;

    2005-01-01

    is investigated by titration, differential scanning calorimetry (DSC) and capillary rheometry. The titration experiments indicates that the polymerization is a block copolymerization and the DSC result show that the blocks of poly(N-isopropylacrylamide) are not randomly distributed in the microgels. Capillary...... concentrations of acrylic acid as co-monomer. The microgels have a charge density between 0.2 and 0.9 mmol/g.   Preliminary filtration experiments show that filtration properties of the microgel model system significantly differs from the properties for inorganic colloidals such as titaniumdioxid....

  8. Synthesis of hemicellulose-acrylic acid graft copolymer super water absorbent resin by ultrasonic irradiation technology

    OpenAIRE

    Liu, Fangfang; Conghui DU; Linya ZHANG

    2015-01-01

    The hemicellulose super water absorbent resin is prepared by using ultrasonic irradiation technology, with the waste liquid produced during the preparation of viscose fiber which contains a large amount of hemicellulose as raw material, acrylic acid as graft monomer, N,N’-methylene bis acrylamide (NMBA) as cross linking agent, and (NH4)2S2O8-NaHSO3 as the redox initiation system. The synthesis conditions, structure and water absorption ability of resin are discussed. The results indicate that...

  9. Depletion of abundant plasma proteins by poly(N-isopropylacrylamide-acrylic acid) hydrogel particles

    DEFF Research Database (Denmark)

    Such-Sanmartín, Gerard; Ventura-Espejo, Estela; Jensen, Ole N

    2014-01-01

    the application of pH-sensitive poly(N-isopropylacrylamide-acrylic acid) hydrogel particles for removal of abundant plasma proteins, prior to proteome analysis by MS. Protein depletion occurs by two separate mechanisms: (1) hydrogel particles incubated with low concentrations of plasma capture abundant proteins...... at higher efficiency than low abundance proteins, which are enriched in the supernatants, whereas (2) hydrogel particles incubated with high concentrations of plasma capture and irreversibly trap abundant proteins. During the elution step, irreversibly trapped proteins remain captured while low abundance...... (SRM) liquid chromatography (LC)-MS/MS. This novel use of hydrogel particles opens new perspectives for biomarker analysis based on mass spectrometry....

  10. Synthesis of carboxymethylcellulose/acrylic acid hydrogels with superabsorbent properties by radiation-initiated crosslinking

    Science.gov (United States)

    Fekete, Tamás; Borsa, Judit; Takács, Erzsébet; Wojnárovits, László

    2016-07-01

    Superabsorbent hydrogels were prepared by gamma irradiation from aqueous solutions of carboxymethylcellulose (CMC) and acrylic acid (AAc) with varying CMC:AAc ratio. By partially replacing the CMC with AAc the gelation increased and led to a higher gel fraction and lower water uptake. Moreover, the gelation required significantly milder synthesis conditions. Decreasing both the dose and the solute concentration in the presence of AAc led to gels with higher gel fraction and higher degree of swelling compared to pure CMC gels. Increasing the AAc content up to 10% proved to be very effective, while very high AAc content (over 50%) hindered the gelation process.

  11. GRAFTING ONTO WOOL V. RADIATION-INITIATED GRAFTING OF ACRYLIC ACID ONTO WOOL FIBER

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xin; LI Cui; ZHOU Zixiong; WANG Tiandiao; CHEN Shanming

    1994-01-01

    This paper deals with graft copolymerization of acrylic acid (AA) onto Xinjiang fine wool fiber in aqueous medium initiated by gamma rays. Graft copolymerization was carried out by the mutual irradiation method in limited air. Percent grafting and percent efficiency have been determined as a function of total dose, dose rate, concentration of monomer, wool weight and reaction temperature. Graft copolymers are characterized with infrared (IR) spectroscopy, scanning electron microscopy (SEM), and X-ray diffractometer. Properties of the grafts were studied, and compared with the virgin fiber.

  12. Novel Routes for the Design of Poly((meth)acrylic acid) Containing Polymer Structures by Controlled Radical Polymerization

    OpenAIRE

    Van Camp, W

    2007-01-01

    Easy preparation of specialty polymers containing poly((meth)acrylic acid) Poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMAA) are well-known polymers in a high number of applications because of their pH-responsive nature, their hydrophylic characteristics and for their interaction with metal ions. PAA, high tech material An increasing part of high tech polymer materials introduce P(M)AA as segments in well-defined polymer structures. These can be block copolymers, polymer brushes, sta...

  13. Antimicrobial and Thermal Properties of Metal Complexes of Grafted Fabrics with Acrylic Acid by Gamma Irradiation

    International Nuclear Information System (INIS)

    Cotton, cotton/PET blend and PET fabrics were treated against microbial effect by radiation - induced grafting of acrylic acid followed by metal complexation with some divalent transition metal ions Co (II), Ni (II) and Cu (II). The microbial resistance was evaluated by testing the mechanical properties of the treated fabrics after burring for one and two weeks in a moist soil reach with microorganisms. Also, the growth of microorganisms was examined by scanning electron microscope (SEM). Moreover, the effect of this treatment on the thermal decomposition behavior was investigated by thermogravimetric analysis (TGA). On the basis of microbial studies, it was found that the metal complexation of the grafted fabrics with acrylic acid enhanced the antimicrobial resistance of the fabrics and the antimicrobial resistance could be arranged according to the metal ions as follows: copper> nickel> cobalt. Also, the thermal stability of different fabrics could be arranged as follow: grafted fabrics complexed with Cu (II) > grafted fabrics complexed with Ni (II) > grafted fabrics complexed with Co (II)

  14. Investigation of small molecular weight poly(acrylic acid) adsorption on γ-alumina

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lei; Luo, Shi-Zhong [College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065 (China); Wang, Bin, E-mail: bin_wang@scu.edu.cn [College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065 (China); Guo, ZhanHu [Chemical and Biomolecular Engineering Department, University of Tennessee, Knoxville, TN 37996 (United States)

    2015-08-01

    Highlights: • Small molecular weight poly(acrylic acid) incorporated on γ-alumina. • PAA adsorbed primarily on outer surface of alumina at low pH. • PAA infiltrated inside alumina pore at high pH. • Polymer chain reptation motion during the infiltration. - Abstract: The interactions between poly(acrylic acid) (PAA) and alumina have been widely investigated. In this study, the pattern of small molecular weight PAA (M{sub W} 3000) interaction with γ-alumina has been dissected. The alumina/PAA hybrids were prepared at pH 4.0, 5.5, and 7.0, respectively. Nitrogen absorption–desorption analysis, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and elemental analysis were conducted to illustrate the characteristics of the hybrids. At pH 4.0, the coiled PAA conformation yielded polymer adsorption primarily on alumina outer surface. At higher pH values, the more stretched PAA molecules were able to infiltrate inside the alumina pores. The phenomenon is explained by the polymer chain reptation motion model. Coiled polymer chains are not oriented enough to penetrate the oxide pore channels. In contrary, stretched polymer chains are more likely to move along the pore channels.

  15. Graft Polymerization of Acrylic Acid and Acrylamide onto BOPET Corona Films

    Institute of Scientific and Technical Information of China (English)

    SUN Jie; TIAN Hua-yu; BAI Yong-ping

    2004-01-01

    The graft polymerization of acrylic acid ( A ) and acrylamide (B) was carried out onto bi- ori ented polyester BOPET corona film. The influence of monomer concentration, reducer concentration and reaction time on the graft polymerization was investigated. The surface tension of the films increased with an increase of monomer concentration, till the concentration of monomer A reached 1.5 × 10-2 g/mL and the concentration of monomer B reached 4.0× 10-2 g/ mL. The surface tension of the films reached a maximum value at 7 × 10 4 M of reducer concentration and subsequently decreased with further increase in reducer concentration. The surface tension of the films increased with the increase of the reaction time apparently within 50min. The grafted corona BO PET films were characterized with IR and XPS. The presence of graft on the film surface was confirmed. The atten uation experiments on grafted corona BOPET films in air at 50℃ and in water were carried out to investigate the persistence of graft polymerization of acrylic acid and arylamide onto BOPET corona films.

  16. Acrylic acid grafted cellulosic Luffa cylindrical fiber for the removal of dye and metal ions.

    Science.gov (United States)

    Gupta, Vinod Kumar; Agarwal, Shilpi; Singh, Prerna; Pathania, Deepak

    2013-10-15

    Acrylic acid grafted cellulosic Luffa cylindrical fiber was utilized for the removal of methylene blue and metal ions from the water system using batch process. The grafted sample used was found to demonstrate a maximum grafting efficiency of 90.8% under concentrations of 0.432×10(-3) mol/L, temperature of 35 °C, time of 60 min and pH of 7.0 respectively. The remarkable improvement in thermal properties of the grafted sample was observed. The formation of new bands in FTIR spectra of grafted sample confirmed the grafting of acrylic acid onto the cellulosic fiber. The maximum adsorption capacity of dye onto adsorbent was observed to be 62.15 mg g(-1) at 175 min. A maximum removal of 45.8% was observed for Mg(2+) as compared to other metal ions. High values of correlation coefficient for methylene blue (0.995) and metal ions such as Mg(2+) (0.996), Ni(2+) (0.995), Zn(2+) (0.996) confirmed the applicability of Langmuir isotherm that assumed a monolayer coverage and uniform activity distribution on the adsorbent surface.

  17. Radiation synthesis of chitosan beads grafted with acrylic acid for metal ions sorption

    Energy Technology Data Exchange (ETDEWEB)

    Benamer, S., E-mail: benamers@yahoo.fr [Division of Nuclear Applications, Centre de Recherche Nucleaire d' Alger, BP-399 Alger-Gare (Algeria); Mahlous, M.; Tahtat, D.; Nacer-Khodja, A.; Arabi, M. [Division of Nuclear Applications, Centre de Recherche Nucleaire d' Alger, BP-399 Alger-Gare (Algeria); Lounici, H.; Mameri, N. [Ecole Nationale Polytechnique d' El-Harrach Alger (Algeria)

    2011-12-15

    Radiation-induced grafting of acrylic acid onto chitosan beads was performed in solution at a dose rate of 20.6 Gy/min of cobalt-60 gamma rays. The effect of absorbed dose on grafting yield was investigated. The characterization of the grafted material was performed by FTIR spectroscopy and the swelling measurements at different pHs. The grafting yield increased with the increase in dose, it reached 80% at 40 kGy irradiation dose. The removal of Pb and Cd ions from aqueous solutions was investigated with both ungrafted and grafted chitosan beads. The sorption behavior of the sorbents was examined through pH, kinetics and equilibrium measurements. Grafted chitosan beads presented higher sorption capacity for both metal ions than unmodified chitosan beads. - Highlights: > Pb and Cd ions are removed from aqueous solution by adsorption on chitosan beads. > Crosslinking process improves chemical stability of chitosan beads. > Radiation grafting of acrylic acid onto chitosan improves its metal adsorption capacity. > Increase in grafting degree enhances the adsorption capacity of the material. > Gamma radiation is a powerful tool for an accurate control of the grafting yield.

  18. Radiation synthesis of chitosan beads grafted with acrylic acid for metal ions sorption

    International Nuclear Information System (INIS)

    Radiation-induced grafting of acrylic acid onto chitosan beads was performed in solution at a dose rate of 20.6 Gy/min of cobalt-60 gamma rays. The effect of absorbed dose on grafting yield was investigated. The characterization of the grafted material was performed by FTIR spectroscopy and the swelling measurements at different pHs. The grafting yield increased with the increase in dose, it reached 80% at 40 kGy irradiation dose. The removal of Pb and Cd ions from aqueous solutions was investigated with both ungrafted and grafted chitosan beads. The sorption behavior of the sorbents was examined through pH, kinetics and equilibrium measurements. Grafted chitosan beads presented higher sorption capacity for both metal ions than unmodified chitosan beads. - Highlights: → Pb and Cd ions are removed from aqueous solution by adsorption on chitosan beads. → Crosslinking process improves chemical stability of chitosan beads. → Radiation grafting of acrylic acid onto chitosan improves its metal adsorption capacity. → Increase in grafting degree enhances the adsorption capacity of the material. → Gamma radiation is a powerful tool for an accurate control of the grafting yield.

  19. Acrylic and Methacrylic Acids Obtaining by Gas-Phase Aldol Condensation of Carbonyl Compounds on B2O3?P2O5?WO3?V2O5/SiO2 Catalysts

    OpenAIRE

    Nebesnyi, Roman; Petelka, Oksana; Shpyrka, Iryna

    2013-01-01

    Prospects of acrylic acid obtaining by acetic acid aldol condensation with formaldehyde are considered. Complex oxide catalysts of the process have been developed. It is shown that raw materials costs in case of acrylic acid production by the condensation method are commeasurable with those in case of its production by oxidation method (main industrial method of acrylic acid production).This method of acrylic acid obtaining may be used as an alternative and enables diversifying the raw materi...

  20. Synthesis and characterization of organometallic copolymers of acrylic acid g-polyethylene, with Mo, Fe, Co, Zn and Ni

    International Nuclear Information System (INIS)

    In this study, the preparation of a series of low density polyethylenes grafted with acrylic acid is presented. The grafting reactions were initiated by different doses of γ radiation; it was observed that grafting increased with the doses of radiation. The prepared copolymers were coordinated with different metals, as Mo, Fe, Co, Zn and Ni. The amount of metal supported on the polymer was determined by atomic absorption. Infrared spectroscopy and thermogravimetric analysis confirmed the metal chelation on the graft copolymer. The film surfaces were observed by scanning electron microscopy. positron annihilation spectroscopy revealed a decrease on the free volume in the low density polyethylene after the grafting with acrylic acid. (Author)

  1. Poly (acrylic acid sodium) grafted carboxymethyl cellulose as a high performance polymer binder for silicon anode in lithium ion batteries

    OpenAIRE

    Liangming Wei; Changxin Chen; Zhongyu Hou; Hao Wei

    2016-01-01

    The design of novel binder systems is required for the high capacity silicon (Si) anodes which usually undergo huge volume change during the charge/discharge cycling. Here, we introduce a poly (acrylic acid sodium)-grafted-carboxymethyl cellulose (NaPAA-g-CMC) copolymer as an excellent binder for Si anode in lithium ion batteries (LIBs). The NaPAA-g-CMC copolymer was prepared via a free radical graft polymerization method by using CMC and acrylic acid as precursors. Unlike the linear, one-dim...

  2. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension using hydrophobically modified poly(acrylic acid).

    Science.gov (United States)

    Chen, J; Chen, M C

    2011-01-01

    A series of hydrophobically modified poly(acrylic acid) (PAA), poly(2-phenoxyethyl acrylate-co-acrylic acid) (poly(PHEA-co-AA)), have been synthesized and characterized by Ubbelohde type viscometry, Nuclear Magnetic Resonance (1H NMR) spectrometry and Differential Scanning Calorimetry (DSC). The shear thinning Non-Newtonian fluid behavior of their aqueous solution and the dependence on pH and hydrophobic group contents were found through apparent viscosity and rheological property investigating. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension was evaluated through visible absorbance data. Decolourization performance of hydrophobically associated polymer indicates two times better than that of PAA. The quantitative relationship was mainly studied. PMID:21866762

  3. UV-induced graft polymerization of acrylic acid in the sub-micronchannels of oxidized PET track-etched membrane

    Science.gov (United States)

    Korolkov, Ilya V.; Mashentseva, Anastassiya A.; Güven, Olgun; Taltenov, Abzal A.

    2015-12-01

    In this article, we report on functionalization of track-etched membrane based on poly(ethylene terephthalate) (PET TeMs) oxidized by advanced oxidation systems and by grafting of acrylic acid using photochemical initiation technique for the purpose of increasing functionality thus expanding its practical application. Among advanced oxidation processes (H2O2/UV) system had been chosen to introduce maximum concentration of carboxylic acid groups. Benzophenone (BP) photo-initiator was first immobilized on the surfaces of cylindrical pores which were later filled with aq. acrylic acid solution. UV-irradiation from both sides of PET TeMs has led to the formation of grafted poly(acrylic acid) (PAA) chains inside the membrane sub-micronchannels. Effect of oxygen-rich surface of PET TeMs on BP adsorption and subsequent process of photo-induced graft polymerization of acrylic acid (AA) were studied by ESR. The surface of oxidized and AA grafted PET TeMs was characterized by UV-vis, ATR-FTIR, XPS spectroscopies and by SEM.

  4. Novel one-dimensional lanthanide acrylic acid complexes: an alternative chain constructed by hydrogen bonding

    Science.gov (United States)

    Li, Hui; Hu, Chang Wen

    2004-12-01

    Novel one-dimensional (1D) chains of three lanthanide complexes La(L 1) 3(CH 3OH)]·CH 3OH (L 1=(E)-3-(2-hydroxyl-phenyl)-acrylic acid) 1, La(L 2) 3(H 2O) 2]·2.75H 2O (L 2=(E)-3-(3-hydroxyl-phenyl)-acrylic acid) 2, and La(L 3) 3(CH 3OH) 2(H 2O)]·CH 3OH (L 3=(E)-3-(4-hydroxyl-phenyl)-acrylic acid) 3 are reported. The crystal structure data are as follows for 1: C 29H 29LaO 11, monoclinic, P2 1/ n, a=15.4289(12) Å, b=7.9585(6) Å, c=23.041(2) Å, β=99.657(2)°, Z=4, R1=0.0637, w R2=0.0919; for 2: C 27H 30.50LaO 13.75, triclinic, P-1, a=8.4719(17) Å, b=13.719(3) Å, c=14.570(3) Å, α=62.19(3)°, β=99.657(2)°, γ=78.22(3)°, Z=2, R1=0.0384, w R2=0.0820; and for 3: C 30H 35LaO 13, monoclinic, P2(1)/ c, a=9.5667(6) Å, b=24.3911(15) Å, c=14.0448(9) Å, β=109.245(2)°, Z=4, R1=0.0374, w R2=0.0630. All the three structure data were collected using graphite monochromated molybdenum Kα radiation and refined using full-matrix least-squares techniques on F 2. These structures show that four kinds of the carboxylato bridge modes are included in these chains to link the La(III) ions. It is the first time that it has been found that the intra-chain hydrogen bonding can construct an alternative chain even, when the coordination bridge mode is the same along the chain (complex 2). There are 2D and 3D hydrogen bonding in the crystal lattices of complexes 1- 3.

  5. Enzyme immobilization on ultrafine cellulose fibers via poly(acrylic acid) electrolyte grafts.

    Science.gov (United States)

    Chen, Hong; Hsieh, You-Lo

    2005-05-20

    Ultrafine cellulose fiber (diameter 200-400 nm) surfaces were grafted with polyacrylic acid (PAA) via either ceric ion initiated polymerization or methacrylation of cellulose with methacrylate chloride (MACl) and subsequent free-radical polymerization of acrylic acid. PAA grafts by ceric ion initiated polymerization increased with increasing reaction time (2-24 h), monomer (0.3-2.4 M), and initiator (1-10 mM) concentrations, and spanned a broad range from 5.5-850%. PAA grafts on the methacrylated cellulose fibers also increased with increasing molar ratios of MACl to cellulosic hydroxyl groups (MACl/OH, 2-6.4) and monomer acrylic acid (AA) to initiator potassium persulfate (KPS) ratios ([AA]/[KPS], 1.5-6), and were in a much narrower range between 12.8% and 29.4%. The adsorption of lipase (at 1 mg/ml lipase and pH 7) and the activity of adsorbed lipase (pH 8.5, 30 degrees C), in both cases decreased with increasing PAA grafts. The highest adsorption and activity of the lipase on the ceric ion initiated grafted fibers were 1.28 g/g PAA and 4.3 U/mg lipase, respectively, at the lowest grafting level of 5.5% PAA, whereas they were 0.33 g/g PAA and 7.1 U/mg lipase, respectively, at 12.8% PAA grafts on the methacrylated and grafted fibers. The properties of the grafted fibers and the absorption behavior and activity of lipase suggest that the PAA grafts are gel-like by ceric-initiated reaction and brush-like by methacrylation and polymerization. The adsorbed lipase on the ceric ion-initiated grafted surface possessed greatly improved organic solvent stability over the crude lipase. The adsorbed lipases exhibited 0.5 and 0.3 of the initial activity in the second and third assay cycles, respectively. PMID:15816022

  6. Electromechanical reliability of flexible transparent electrodes during and after exposure to acrylic acid

    International Nuclear Information System (INIS)

    The effect of deposition temperature on pulsed laser deposition (PLD) fabricated flexible transparent electrodes subjected to mechanical loading, after exposure to acrylic acid, and the combined effect of fatigue and corrosion on sputter-deposited polyester-based indium tin oxide (ITO) films are both investigated in this study. Acrylic acid containing pressure sensitive adhesives, which are commonly used in various flexible device stacks, can corrode the ITO film. In addition, fatigue due to cyclic loading can lead to film cracking. The combined effect of fatigue and corrosion can lead to catastrophic failure of the system. We found that PLD-produced ITO on polyethylene naphthalate samples deposited at 150 °C performs better than samples deposited at 50 °C under uniaxial mechanical loading. They were found to exhibit higher crack onset strain than their 50 °C counterparts. However, they were observed to be more sensitive to increasing acid concentrations. Scanning electron microscopy images show a larger number of adhesive cracks on the surfaces of the 150 °C-deposited samples than the 50 °C-deposited samples. Atomic force microscopy results reveal that the increased temperature causes a significant increase in surface roughness which may affect the corrosion behavior of the ITO film. Furthermore, in situ electrical resistance measurements and crack density analysis suggest that the combination of fatigue and corrosion can cause film failure at low strains, less than those needed for failure with no corrosion. For example, at 0.9% applied strain and 500,000 cycles, the crack density under fatigue–corrosion is 1.7 times that of the fatigue-only case. - Highlights: ► ITO films were deposited on polymers with PLD or magnetron sputtering. ► The combination of fatigue and corrosion was investigated using a custom apparatus. ► Adhesion and film roughness played roles in the fatigue-corrosion behavior

  7. A facile one pot strategy for the synthesis of well-defined polyacrylates from acrylic acid via RAFT polymerization.

    Science.gov (United States)

    Li, Qianbiao; Wang, Taisheng; Dai, Jingwen; Ma, Chao; Jin, Bangkun; Bai, Ruke

    2014-03-28

    A facile one pot strategy for the preparation of linear and hyperbranched polyacrylates has been successfully developed by the combination of in situ esterification of acrylic acid with halogenated compounds promoted by 1,1,3,3-tetramethylguanidine (TMG) and RAFT polymerization. PMID:24534953

  8. Structure-function properties of amylose-oleic acid inclusion complexes grafted with poly(methyl acrylate)

    Science.gov (United States)

    Spherulites, produced by steam jet-cooking high-amylose starch and oleic acid, were grafted with methyl acrylate, both before and after removal of un-complexed amylopectin. For comparison, granular high-amylose corn starch was graft polymerized in a similar manner. The amount of grafted and ungrafte...

  9. On the effect of treating poly(acrylic acid) with argon and tetrafluoromethane plasmas: Kinetics and degradation mechanism

    NARCIS (Netherlands)

    Terlingen, Johannes G.A.; Takens, Gijsbert A.J.; Gaag, van der Frederik J.; Hoffman, Allan S.; Feijen, Jan

    1994-01-01

    Poly(acrylic acid) (PAAc) films were treated with either an argon or a tetrafluoromethane (CF4) plasma and subsequently analyzed with X-ray photoelectron spectroscopy (XPS). PAAc films were decarboxylated during both types of plasma treatments. In addition, during the CF4 plasma treatment, the PAAc

  10. Comparison of various models to describe the charge-pH dependence of poly(acrylic acid)

    NARCIS (Netherlands)

    Lützenkirchen, J.; Male, van J.; Leermakers, F.A.M.; Sjöberg, S.

    2011-01-01

    The charge of poly(acrylic acid) (PAA) in dilute aqueous solutions depends on pH and ionic strength. We report new experimental data and test various models to describe the deprotonation of PAA in three different NaCl concentrations. A simple surface complexation approach is found to be very success

  11. Poly-Acrylic Acid Derivatives as Diesel Flow Improver for Paraffin-Based Daqing Diesel

    Institute of Scientific and Technical Information of China (English)

    Cuiyu Jiang; Ming Xu; Xiaoli Xi; Panlun Qi; Hongyan Shang

    2006-01-01

    Since the diesel products from paraffin-based Daqing crude oil showed low sensitivity to certain commercial diesel pour point depressant (PPDs) that resulted from the high content of paraffin, certain poly-acrylic acid derivatives (PADE) with-COOR,-COOH,-CONHR, and -COO-NH3+R groups by molecular design on the mechanics of diesel; PPDs were synthesized and evaluated as cold flow improver for Daqing 0# diesel in this paper. The pure PADE was superior to the commercial PPDs and displayed a substantial ability of wax crystals dispersion. There was a synergistic effect among the PADE and T1804 and secondary amine. The synergism clearly improved the low temperature performance of Daqing diesel products and could reduce the cold filter plugging point of 0# diesel by 6-7 ℃.

  12. Thermal degradation of biopolymer binders: the example of starch-poly(acrylic acid

    Directory of Open Access Journals (Sweden)

    B. Grabowska

    2010-01-01

    Full Text Available To characterise a polymer, it is of fundamental importance to determine its parameters, like the temperatures of destruction, vitrification, melting point, specific mass losses or polymorphic transformations, which frequently determine the quality of the product and its applications. Thermal analyses were conducted of samples of a biopolymer binder: a starch-poly(acrylic acid composition and a moulding sand with a biopolymer binder previously hardened with microwaves. In order to determine the thermal stability of the examined samples by determining the destruction temperature and the thermal effects of transformations taking place during heating, FTIR spectroscopy and thermal analysis (DSC, DTG, TG methods were used. In addition, volatile products of degradation were analysed using the thermogravimetry (TG method coupled online with mass spectrometry (MS. These examinations were also aimed at identifying the changes that can take place in the moulding sand when it comes into contact with liquid metal.

  13. Dielectric properties of solution-grown-undoped and acrylic-acid-doped ethyl cellulose

    Indian Academy of Sciences (India)

    P K Khare; Sandeep K Jain

    2000-02-01

    Dielectric capacities and losses were measured, in the temperature (50–170°C) and frequency (01–100 kHz range), for undoped and acrylic acid (AA) doped ethyl cellulose (EC) films (thickness about 20 m) with progressive increase in the concentration of dopant in the polymer matrix. The variation of capacity with temperature is attributed to thermal expansion in the lower temperature region to the orientation of dipolar molecules in the neighbourhood of glass transition temperature () and random thermal motion of molecules above . The dielectric losses exhibit a broad peak. Doping with AA is found to affect the magnitude and position of the peak. AA is found to have a two-fold action. Firstly, it enhances the chain mobility and secondly, it increases the dielectric loss by forming charge transfer complexes.

  14. Graft polymerization of acrylic acid onto chitin nanofiber to improve dispersibility in basic water.

    Science.gov (United States)

    Ifuku, Shinsuke; Iwasaki, Masayoshi; Morimoto, Minoru; Saimoto, Hiroyuki

    2012-09-01

    Graft copolymerization of acrylic acid (AA) on chitin nanofibers was carried out with potassium persulfate as a free radical initiator in an aqueous medium. The molar ratio of grafted AA increased with the AA concentration. The grafted chitin nanofibers were characterized by FT-IR, FE-SEM, UV-vis, XRD, and TGA. After polymerization, the characteristic morphology of chitin nanofibers was maintained. Chitin nanofibers grafted with AA were efficiently dissociated and dispersed homogeneously in basic water because of the electrostatic repulsion effect between nanofibers. AA was grafted on the surface and amorphous part of chitin nanofibers, and the original crystalline structure of α-chitin was maintained. At 330 °C, the weight residue of the graft copolymer increased with the grafted AA content. PMID:24751085

  15. Hydrophobically modified polyelectrolytes I. Dilute solution properties of fluorocarbon-containingpoly(acrylic acid)

    Institute of Scientific and Technical Information of China (English)

    ZHOU, Hui(周晖); SONG, Guo-Qiang(宋国强); ZHANG, Yun-Xiang(章云祥); DIEING, Reinhold; MA, Lian; HAEUSSLING, Lukas

    2000-01-01

    Dilute solution viscosity of fluorocarbon-containing hydrophobically modified poly(acrylic acid) was measured in aqueous solutions of various NaCl concentrations. The intrinsic viscosity ([η]) and Huggins coefficient (kH) were evaluated using Huggins equations. It is found that, at low NaCl concentration, the modified polymers exhibit values of intrinsic viscosity ( [η] ) and Huggins coefficient (kH) similar to those of unmodified polymers. For both of the modified and unmodified polymers, the intrinsic viscosity decreases with increase of NaCl concentration, while the Huggins coefficient increases upon addition of NaCl. But the variation of [η] and kH is more significant for the modified polymers, which reflects the enhanced intra- and intermolecular hydrophobic association at higher NaCl concentration.

  16. Superabsorbent Prepared by Radiation Induced Graft Copolymerization of Acrylic Acid onto Cassava Starch. Chapter 18

    International Nuclear Information System (INIS)

    Superabsorbent was synthesized by radiation induced graft polymerization of acrylic acid onto cassava starch. Parameters such as the absorbed dose and the amount of monomer were investigated in order to determine the optimum conditions for the grafting polymerization. Water retention, germination percentage, and germination energy were also determined in order to evaluate the possibility of superabsorbent in agricultural applications, especially in arid regions. The graft copolymer was characterized by the Fourier transform infrared spectroscopy (FTIR). Results indicated that the sand mixed with 0.1% wt superabsorbent could absorb more water than the sand without superabsorbent. The germination energy of corn seeds mixed with 0.5% superabsorbent was obviously higher than those without superabsorbent. These experimental results showed that the superabsorbent has considerable effects on seed germination and the growth of young plants. (author)

  17. Poly(acrylic acid)-poly(ethylene glycol) nanoparticles designed for ophthalmic drug delivery.

    Science.gov (United States)

    Vasi, Ana-Maria; Popa, Marcel Ionel; Tanase, Edi Constantin; Butnaru, Maria; Verestiuc, Liliana

    2014-02-01

    Poly(acrylic acid) (PAA) and poly(ethylene glycol) (PEG), four-arm, amine-terminated particles with nanometer size and spherical shape were obtained by the polymers cross-linking, via activation with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride, in a w/o emulsion. The morphology and surface charge of the final particles are strongly dependent on the molar ratio of PAA-PEG and the PAA concentration. The physicochemical characteristics correlated with the drug-loading capacity, in vitro and ex vivo release kinetics of pilocarpine hydrochloride and biocompatibility results indicate that these nanoparticles exhibit the prerequisite behavior for use as carriers of ophthalmic drugs. PMID:24357331

  18. Michael-type addition of azoles of broad-scale acidity to methyl acrylate

    Directory of Open Access Journals (Sweden)

    Krzysztof Z. Walczak

    2011-02-01

    Full Text Available An optimisation of Michael-type addition of azole derivatives of broad-scale acidity – ranging from 5.20 to 15.00 pKa units – namely 4-nitropyrazole, 3,5-dimethyl-4-nitropyrazole, 4(5-nitroimidazole, 4,5-diphenylimidazole, 4,5-dicyanoimidazole, 2-methyl-4(5-nitroimidazole, 5(4-bromo-2-methyl-4(5-nitroimidazole and 3-nitro-1,2,4-triazole to methyl acrylate as an acceptor was carried out. The optimisation process involved the use of an appropriate basic catalyst (DBU, DIPEA, NaOH, NaH, TEDA, a donor/base/acceptor ratio and the reaction temperature. The reactions were performed in DMF as solvent. Target Michael adducts were obtained in medium to excellent yields. Importantly, for imidazole and 1,2,4-triazole derivatives, no corresponding regioisomers were obtained.

  19. Cascade enzymatic catalysis in poly(acrylic acid) brushes-nanospherical silica for glucose detection.

    Science.gov (United States)

    Zhao, Yan; Wang, Ying; Zhang, Xiaobin; Kong, Rongmei; Xia, Lian; Qu, Fengli

    2016-08-01

    The ultrasensitive monitoring of glucose with a fast and accurate method is significant in potential therapeutics and optimizes protein biosynthesis. Incorporation of enzyme into matrix is considered as promising candidates for constructing highly sensitive glucose-responsive systems. In this study, three-dimensional poly(acrylic acid) brushes-nanospherical silica (PAA-nano silica) with high amplification capability and stability were used to covalently immobilize bienzymes for cascade enzymatic catalysis. The major advantages of PAA-nano silica-bienzyme co-incorporation is that the enzymes are proximity distribution, and such close confinement both minimized the diffusion of intermediates among the enzymes in the consecutive reaction and improve the utilization efficiency of enzymes, thereby enhancing the overall reaction efficiency and specificity. Thus, this present bienzymatic biosensor shows robust signal amplification and ultrasensitivity of glucose-responsive properties with a detection limit of 0.04μM. PMID:27216683

  20. Study on swelling behaviour of hydrogel based on acrylic acid and pectin from dragon fruit

    Science.gov (United States)

    Abdullah, Mohd Fadzlanor; Lazim, Azwani Mat

    2014-09-01

    Biocompatible hydrogel based on acrylic acid (AA) and pectin was synthesized using gamma irradiation technique. AA was grafted onto pectin backbone that was extracted from dragon fruit under pH 3.5 and extracts and ethanol ratios (ER) 1:0.5. The optimum hydrogel system with high swelling capacity was obtained by varying the dose of radiation and ratio of pectin:AA. FTIR-ATR spectroscopy was used to verify the interaction while thermal properties were analyzed by TGA and DSC. Swelling studies was carried out in aqueous solutions with different pH values as to determine the pH sensitivity. The results show that the hydrogel with a ratio of 2:3 (pectin:AA) and 30 kGy radiation dose has the highest swelling properties at pH of 10.

  1. Poly(acrylic acid surface grafted polypropylene films: Near surface and bulk mechanical response

    Directory of Open Access Journals (Sweden)

    2008-11-01

    Full Text Available Radical photo-grafting polymerization constitutes a promising technique for introducing functional groups onto surfaces of polypropylene films. According to their final use, surface grafting should be done without affecting overall mechanical properties. In this work the tensile drawing, fracture and biaxial impact response of biaxially oriented polypropylene commercial films grafted with poly(acrylic acid (PAA were investigated in terms of film orientation and surface modification. The variations of surface roughness, elastic modulus, hardness and resistance to permanent deformation induced by the chemical treatment were assessed by depth sensing indentation. As a consequence of chemical modification the optical, transport and wettability properties of the films were successfully varied. The introduced chains generated a PAA-grafted layer, which is stiffer and harder than the neat polypropylene surface. Regardless of the surface changes, it was proven that this kind of grafting procedure does not detriment bulk mechanical properties of the PP film.

  2. Preparation of porous chitosan-poly(acrylic acid)-calcium phosphate hybrid nanoparticles via mineralization

    Institute of Scientific and Technical Information of China (English)

    CHEN ChangJing; DENG Yu; YAN ErYun; HU Yong; JIANG XiQun

    2009-01-01

    In this work,the preparation of chitosan-poly(acrylic acid)-calcium phosphate hybrid nanoparticles (CS-PAA-CaP NP) based on the mineralization of calcium phosphate (CAP) on the surface of chitosan-poly (acrylic acid) nanoparticles (CS-PAA NPs) was reported. CS-PAA-CaP NPs were achieved by directly adding ammonia to the aqueous solution of CS-PAA nanoparticles or by thermal decomposition of urea in the aqueous solution of CS-PAA nanoparticles,resulting in the mineralization of CaP on the surface of CS-PAA NPs. Through these two routes,especially using urea as a pH-regulator,the precipitation of CS-PAA NPs,a common occurrence in basic environment,was avoided. The size,morphology and ingredient of CS-PAA-CaP hybrid nanoparticles were characterized by dynamic light scattering (DLS),transmission electron microscope (TEM),scanning electron microscope (SEM),thermogravimetry analysis (TGA) and X-ray diffractometer (XRD). When urea was used as the pH regulator to facilitate the mineralization during the thermal urea decomposition procedure,regular CS-PAA-CaP hybrid nanoparticles with a porosity-structural CaP shells and 400-600 nm size were obtained. TGA result revealed that the hybrid NPs contained approximately 23% inorganic component,which was consistent with the ratio of starting materials. The XRD spectra of hybrid nanoparticles indicated that dicalcium phosphate (DCP:CaHPO4) crystal was a dominant component of mineralization.The porous structure of the CS-PAA-CaP hybrid NPs might be greatly useful in pharmaceutical and other medical applications.

  3. Swelling characteristics of acrylic acid polyelectrolyte hydrogel in a dc electric field

    Science.gov (United States)

    Jabbari, Esmaiel; Tavakoli, Javad; Sarvestani, Alireza S.

    2007-10-01

    A novel application of environmentally sensitive polyelectrolytes is in the fabrication of BioMEMS devices as sensors and actuators. Poly(acrylic acid) (PAA) gels are anionic polyelectrolyte networks that exhibit volume expansion in aqueous physiological environments. When an electric field is applied to PAA polyelectrolyte gels, the fixed anionic polyelectrolyte charges and the requirement of electro-neutrality in the network generate an osmotic pressure, above that in the absence of the electric field, to expand the network. The objective of this research was to investigate the effect of an externally applied dc electric field on the volume expansion of the PAA polyelectrolyte gel in a simulated physiological solution of phosphate buffer saline (PBS). For swelling studies in the electric field, two platinum-coated plates, as electrodes, were wrapped in a polyethylene sheet to protect the plates from corrosion and placed vertically in a vessel filled with PBS. The plates were placed on a rail such that the distance between the two plates could be adjusted. The PAA gel was synthesized by free radical crosslinking of acrylic acid monomer with ethylene glycol dimethacrylate (EGDMA) crosslinker. Our results demonstrate that volume expansion depends on the intensity of the electric field, the PAA network density, network homogeneity, and the position of the gel in the field relative to positive/negative electrodes. Our model predictions for PAA volume expansion, based on the dilute electrolyte concentration in the gel network, is in excellent agreement with the experimental findings in the high-electric-field regime (250-300 Newton/Coulomb).

  4. Fluorescence and Judd-Ofelt analysis of rare earth complexes with maleic anhydride and acrylic acid

    Institute of Scientific and Technical Information of China (English)

    WEN Shipeng; ZHANG Xiaoping; HU Shui; ZHANG Liqun; LIU Li

    2008-01-01

    Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTFA=2-Thenoyltrifluoroacetone, Phen=1,10-phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluorescence properties of Eu(TTA)2(Phen)(H2O) and the reactivity of acrylic acid and maleic anhydride with radicals, were synthesized. The two complexes were characterized by elemental analysis, infrared (IR) spectra, and X-ray photoelectron spectroscopy (XPS). Based on the data shown from the fluorescent spectra of the Eu-MA and Eu-AA complexes, the Ωλ (λ=2 and 4) experimental intensity parameters were calculated. The results demonstrated that the Ω2 intensity parameters for the two complexes were smaller than those for the Eu(TTA)2(Phen)(H2O) complex, indicating that a less symmetri-cal chemical environment existed in the complexes. It implied that the radiative efficiency of the 5D0 of these two complexes could be en-hanced by ligand of MA and AA, respectively. The luminescent lifetime of the Eu-AA (τ=7.26×10-4 s) or Eu-MA complex (τ=-8.12×10-4 s) was higher than that of the Eu(TTA)2(Phen)(H2O) complex, which was attributed to the substitution of the water molecule (H2O) in Eu(TTA)2(Phen)(H2O) by the MA or AA ligand.

  5. Synthesis of Hydrophobically Modified Poly(acrylic acid) Gels and Interaction of the Gels with Cationic/Anionic Surfactants

    Institute of Scientific and Technical Information of China (English)

    TIAN,Qin(田琴); TANG,Xiao-Zhen(唐小真); ZHUANG,Dong-Qing(庄东青); ZHANG,Yun-Xiang(章云祥)

    2002-01-01

    Poly( acrylic acid) (PAA) gel network with only chemical crosslinking and hydrophobically modified PAA (HM-PAA)gels with both chemical and physical crosslinking were synthesized by radical polymerization in tert-butanol, using ethylene glycol dimethacrylate (EGDMA) as crosslinker, and 2-(Nethylperfiuorooctanesulfoamido) ethyl methacrylate ( FMA ),stearyl acrylate (SA) or lauryl acrylate (LA) as hydrophobic comonomer respectively. The effect of the fractions and the species of the hydrophobes on swelling properties of HM-PAA gels and the interaction of gels and surfactants were studied.The results showed that the swelling ratio of HM-PAA gels exhibited a sharp decrease with increasing hydrophobic comonomer concentration, which could be ascribed to the formation of strong hydrophobic association among hydrophobic groups. It was proved that two kinds of binding mechanisms of surfactant/gel and different kinds of hydrophobic dusters existed in gels containing both physical and chemical networks.

  6. Corrosion Inhibitive Evaluation of an Environmentally Friendly Water-Base Acrylic Terpolymer on Mild Steel in Hydrochloric Acid Media

    Science.gov (United States)

    Azghandi, Mojtaba Vakili; Davoodi, Ali; Farzi, Gholam Ali; Kosari, Ali

    2013-12-01

    The corrosion inhibitive performance of an environmentally friendly water-base acrylic terpolymer [methyl methacrylate/Butyl Acrylate/Acrylic acid (ATP)] on mild steel in 1 M HCl was investigated by alternating current and direct current electrochemical techniques and the quantum chemical method. An efficiency of more than 97 pct was obtained with 0.8 mmol/L ATP. The increase in inhibitor concentration and immersion time has a positive effect, while the temperature influence is negligible on the inhibitor efficiency. The present terpolymer obeys the Langmuir isotherm, and thermodynamic calculation reveals a chemisorption type on the surface. Density functional calculations showed that the lone pairs of electrons of oxygen in the structure of three monomers are suitable sites to adsorb onto the metal surface. Finally, in the presence of ATP, a decrease in surface roughness and corrosion attacks was demonstrated by atomic force microscopy and optical microscopy examinations, respectively.

  7. Self-assembly and the hemolysis effect of monodisperse N,N-diethylacrylamide/acrylic acid nanogels with high contents of acrylic acid.

    Science.gov (United States)

    Li, Xueting; Zhao, Di; Shi, Xiaodi; Qiu, Gao; Lu, Xihua

    2016-09-21

    Monodisperse temperature/pH sensitive poly(N,N-diethylacrylamide/acrylic acid) (P(DEA/AAc)) nanogels with high contents of AAc up to 40 wt% have been prepared. In this study, it was unexpectedly found that the polydispersity of the nanogels with 40 wt% AAc strongly depended on the initiator concentration. Monodisperse P(DEA/AA) nanogels were synthesized only at a very low concentration of initiator. The phase transition behavior of the nanogels in water can be tuned by pH and temperature. Due to low polydispersity, the nanogels self-assembled into colloidal crystals at different temperatures below the volume phase transition temperature (VPTT). The sharp Bragg peaks of the crystals were significantly blue-shifted as the concentration of the nanogels was increased. In contrast, the condensed suspensions without crystals still exhibited clear colours resulting from a short-range order structure. The reflection spectra of the coloured suspensions showed that the peak wavelength became a bit longer and much broader. And the reflection intensity of the coloured suspensions was much weaker. Elastic and coloured crosslinked nanogel networks prepared by a one-pot and rapid light-initiated crosslinking method showed responses to pH and temperature. Furthermore, the interaction between the nanogels and peptide melittin was investigated. The results showed that an increasing AAc composition led to more efficient inhibition of the hemolytic activity of melittin. The nanogels with 40 wt% AAc composition completely inhibited hemolytic activity at a nanogel concentration of 400 µg ml(-1). Thus, monodisperse P(DEA/AAc) nanogels of high AAc composition may be developed as efficient substitutes for antibody-based antidotes. Owing to the combined influence of the periodic structure of the crystals of the nanogels and an efficient neutralization effect, the P(DEA/AAc) nanogels show promise to become an integral step for preparing valuable naked-eye biosensors as simple, cheap and

  8. Thiomers: Influence of molecular mass and thiol group content of poly(acrylic acid) on efflux pump inhibition.

    Science.gov (United States)

    Grabovac, Vjera; Laffleur, Flavia; Bernkop-Schnürch, Andreas

    2015-09-30

    The aim of the present study was to investigate the influence of molecular mass and thiol group content of poly(acrylic acid)-cysteine conjugates on the permeation of sulforhodamine 101 and penicillin G. acting as substrates for multidrug resistance-associated protein 2 efflux pump. Poly(acrylic acids) of 2 kDa, 100 kDa, 250 kDa, 450 kDa and 3000 kDa were conjugated with cysteine. The thiol group content of all these polymers was in the range from 343.3 ± 48.4 μmol/g to 450.3 ± 76.1 μmol/g. Transport studies were performed on rat small intestine mounted in Ussing-type chambers. Since 250 kDa poly(acrylic acid) showed the highest permeation enhancing effect, additionally thiolated 250 kDa polyacrylates displaying 157.2 μmol/g, 223.0 ± 18.1 and 355.9 μmol/g thiol groups were synthesized in order to investigate the influence of thiol group content on the permeation enhancement. The permeation of sulforhodamine was 3.93- and 3.85-fold improved using 250 kDa poly(acrylic acid)-cysteine conjugate exhibiting 355.9 ± 39.5 μmol/g and 223.0 ± 18.1 μmol/g thiol groups. Using the same conjugates the permeation of penicillin G was 1.70- and 1.59-fold improved, respectively. The study demonstrates that thiolated poly(acrylic acid) inhibits Mrp2 mediated transport and that the extent of inhibition depends on the molecular mass and degree of thiolation of the polymer. PMID:26238816

  9. Controlled release of insulin through hydrogels of (acrylic acid)/trimethylolpropane triacrylate

    Science.gov (United States)

    Raymundi, Vanessa C.; Aguiar, Leandro G.; Souza, Esmar F.; Sato, Ana C.; Giudici, Reinaldo

    2015-12-01

    Hydrogels of poly(acrylic acid) crosslinked with trimethylolpropane triacrylate (TMPTA) were produced through solution polymerization. After these hydrogels were loaded with insulin solution, they evidenced swelling. Experiments of controlled release of insulin through the hydrogels were performed in acidic and basic media in order to evaluate the rates of release of this protein provided by the referred copolymer. Additionally, a mathematical description of the system based on differential mass balance was made and simulated in MATLAB. The model consists of a system of differential equations which was solved numerically. As expected, the values of swelling index at the equilibrium and the rates of insulin release were inversely proportional to the degree of crosslinking. The mathematical model provided reliable predictions of release profiles with fitted values of diffusivity of insulin through the hydrogels in the range of 6.0 × 10-7-1.3 × 10-6 cm2/s. The fitted and experimental values of partition coefficients of insulin between the hydrogel and the medium were lower for basic media, pointing out good affinity of insulin for these media in comparison to the acidic solutions.

  10. pH-Responsive Behavior of Poly(acrylic acid) Brushes of Varying Thickness

    Science.gov (United States)

    Yadav, Vivek; Robertson, Megan; Conrad, Jacinta

    2015-03-01

    We have investigated the pH-dependent response of polyelectrolyte brushes of varying thickness. Our model system consists of poly(acrylic acid) brushes, which change from hydrophobic and neutral at low pH to hydrophilic and negatively charged at high pH, synthesized using a grafting-from approach at constant grafting density. As the polymer brush thickness increased, the brushes exhibited greater hysteresis in static water contact angle as a function of pH. We extracted the pKa of the polymer brushes from contact angle measurements. The relationship between the pKa and brush thickness depended on the order in which the brushes were exposed to solutions of varying pH: pKa decreased on increasing brush thickness when going from basic to acidic medium whereas pKa increased on increasing brush thickness when going from acidic to basic medium. We speculate that the origin of hysteresis can be explained by pH-dependent conformational changes in these polyelectrolyte brushes.

  11. Controlled release of insulin through hydrogels of (acrylic acid)/trimethylolpropane triacrylate

    Science.gov (United States)

    Raymundi, Vanessa C.; Aguiar, Leandro G.; Souza, Esmar F.; Sato, Ana C.; Giudici, Reinaldo

    2016-10-01

    Hydrogels of poly(acrylic acid) crosslinked with trimethylolpropane triacrylate (TMPTA) were produced through solution polymerization. After these hydrogels were loaded with insulin solution, they evidenced swelling. Experiments of controlled release of insulin through the hydrogels were performed in acidic and basic media in order to evaluate the rates of release of this protein provided by the referred copolymer. Additionally, a mathematical description of the system based on differential mass balance was made and simulated in MATLAB. The model consists of a system of differential equations which was solved numerically. As expected, the values of swelling index at the equilibrium and the rates of insulin release were inversely proportional to the degree of crosslinking. The mathematical model provided reliable predictions of release profiles with fitted values of diffusivity of insulin through the hydrogels in the range of 6.0 × 10-7-1.3 × 10-6 cm2/s. The fitted and experimental values of partition coefficients of insulin between the hydrogel and the medium were lower for basic media, pointing out good affinity of insulin for these media in comparison to the acidic solutions.

  12. Fabrication and Characterization of Gd-DTPA-Loaded Chitosan-Poly(Acrylic Acid) Nanoparticles for Magnetic Resonance Imaging.

    Science.gov (United States)

    Ahmed, Arsalan; Zhang, Chao; Guo, Jian; Hu, Yong; Jiang, Xiqun

    2015-08-01

    Gd-DTPA-loaded chitosan-poly(acrylic acid) nanoparticles (Gd-DTPA@CS-PAA NPs) were formulated based on the reaction system of water-soluble polymer-monomer pairs of acrylic acid in chitosan solution followed by sorption of Gd-DTPA. Morphological investigations revealed the spherical shape of these NPs with about 220 nm particle size. These NPs showed charge reversal characteristic in acidic solution. In vitro and in vivo magnetic characteristics of these NPs were explored to estimate their utilization in targeted enhanced magnetic resonance imaging. Relaxation studies showed that these NPs possessed pH susceptible relaxation properties, which could introduce in vivo-specific distribution of contrast agent. MRI experiment showed that these nanoparticles had better results in contrast enhancement, and the concentration of contrast agent increased in liver and brain with increment in time. Thus, these NPs could maintain in vivo long circulation and high relaxation rate and were suitable agents for magnetic resonance imaging.

  13. Synthesis of poly acrylic acid modified silver nanoparticles and their antimicrobial activities

    International Nuclear Information System (INIS)

    Poly acrylic acid modified silver (Ag/PAA) nanoparticles (NPs) have been successfully synthesized in the aqueous solution by using tannic acid as a reductant. The structure, morphology and composition of Ag/PAA NPs were characterized by various techniques such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible absorption spectroscopy (UV–vis) and thermogravimetry analysis (TGA). The results show that PAA/Ag NPs have a quasi-ball shape with an average diameter of 10 nm and exhibit well crystalline, and the reaction conditions have some effect on products morphology and size distribution. In addition, the as-synthesized Ag/PAA NPs antimicrobial activities against Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were evaluated by the methods of broth dilution, cup diffusion, optical density (OD600) and electron microscopy observation. The as-synthesized Ag/PAA NPs exhibit excellent antibacterial activity. The antimicrobial mechanism may be attributed to the damaging of bacterial cell membrane and causing leakage of cytoplasm. - Highlights: • Dispersed Ag/PAA NPs with small size were synthesized. • Ag/PAA NPs exhibited excellent antimicrobial properties. • Interaction mechanism between Ag/PAA NPs and bacteria was verified

  14. Synthesis of poly acrylic acid modified silver nanoparticles and their antimicrobial activities

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Zhihui [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China); Wang, Zhihua [Institute of Environmental and Analytical Sciences, College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004 (China); Sun, Lei, E-mail: sunlei@henu.edu.cn [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China); Li, Binjie [Key Laboratory of Cellular and Molecular Immunology, Henan University, Kaifeng 475004 (China); Zhao, Yanbao [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China)

    2014-08-01

    Poly acrylic acid modified silver (Ag/PAA) nanoparticles (NPs) have been successfully synthesized in the aqueous solution by using tannic acid as a reductant. The structure, morphology and composition of Ag/PAA NPs were characterized by various techniques such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible absorption spectroscopy (UV–vis) and thermogravimetry analysis (TGA). The results show that PAA/Ag NPs have a quasi-ball shape with an average diameter of 10 nm and exhibit well crystalline, and the reaction conditions have some effect on products morphology and size distribution. In addition, the as-synthesized Ag/PAA NPs antimicrobial activities against Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were evaluated by the methods of broth dilution, cup diffusion, optical density (OD600) and electron microscopy observation. The as-synthesized Ag/PAA NPs exhibit excellent antibacterial activity. The antimicrobial mechanism may be attributed to the damaging of bacterial cell membrane and causing leakage of cytoplasm. - Highlights: • Dispersed Ag/PAA NPs with small size were synthesized. • Ag/PAA NPs exhibited excellent antimicrobial properties. • Interaction mechanism between Ag/PAA NPs and bacteria was verified.

  15. A MORPHOLOGICAL STUDY OF POLY(DIVINYLBENZENE-co-ACRYLIC ACID) IN CROSSLINKING PRECIPITATION POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    Feng Bai; Xin-lin Yang; Wen-qiang Huang

    2006-01-01

    Divinylbenzene-80 (DVB-80) and polar monomer acrylic acid (AA) having hydrogen bonding at a total monomer loading of 5 vol% were precipitated-copolymerized in a variety of organic solvents with 2,2'-azobis(isobutyronitrile) (AIBN) as initiator. The experiments were investigated from a two-dimensional matrix, i.e., the actual crosslinking degree of DVB varying from 0 to 80% and the solvent composition varying from 0 to 100% of toluene mixture with acetonitrile, when the mixture of acetonitrile and toluene was used as the reaction solvent. Under various reaction conditions, six distinct morphologies including soluble polymers, swellable microgels, coagulum, irregular microparticles, and nano-/micrometer microspheres were formed and the structures of these polymer architectures were described. A morphological map was utilized to discuss the effects of both crosslinking degree of DVB and composition of solvent on the transitions between morphology domains. The results demonstrated that the microspheres are formed by an internal contraction due to the marginal solvency of the continuous phase and the crosslinking of the polymer network through the covalent bonding from DVB as well as the interchain hydrogen-bonding between the carboxylic acid units.

  16. Synthesis of poly(acrylic acid-maleic acid)SiO2/Al2O3 as novel composite material for cesium removal from acidic solutions

    International Nuclear Information System (INIS)

    A novel composite material of SiO2-Al2O3 based on poly(acrylic acid-maleic acid) was synthesized by irradiated with 60Co γ-rays at a dose of 25 KGy. The composite material was characterized using FTIR, TGA and BET surface area. Adsorption of 134Cs from HNO3 was studied as a function of contact time, temperature and concentration of Cs. Sorption behavior of 134Cs in different concentration of HCl, HNO3, acetic acid, ascorbic acid, citric acid, NaCl and NaNO3 solutions has been investigated. It can be concluded that the P(AA-MA)/SiO2/Al2O3 is promising adsorbent for Cs removal from acidic liquid radioactive waste. (author)

  17. The influence of poly(acrylic) acid number average molecular weight and concentration in solution on the compressive fracture strength and modulus of a glass-ionomer restorative.

    LENUS (Irish Health Repository)

    Dowling, Adam H

    2011-06-01

    The aim was to investigate the influence of number average molecular weight and concentration of the poly(acrylic) acid (PAA) liquid constituent of a GI restorative on the compressive fracture strength (σ) and modulus (E).

  18. Synthesis of Hydrogel Based on Nata De Coco and Acrylic Acid as Co-Monomer Using Free Radical Polymerization Method

    International Nuclear Information System (INIS)

    Nata de Coco or known as bacterial cellulose is produced by Acetobacter xylinum where it is more stable than plant cellulose. Moreover, it also provides outstanding advantages to be developed as an environmental responsive hydrogels. In this study the bacterial cellulose-g-acrylic acid hydrogel was synthesized by using a free radical polymerization method. Ammonium persulfate (APS) was used to initiate the reaction, while N,N'-methylene bis acrylamide has been used as the crosslinking agent. In order to test the hydrogel respond, swelling tests were made at different pH. Furthermore, ATR-FTIR analysis was used to determine the interactions between bacterial cellulose and acrylic acid. Finally, the determination of glass transition (Tg) was made by using DSC. (author)

  19. A Novel Approach for the Desalination of Seawater by Means of Reusable Poly(acrylic acid) Hydrogels and Mechanical Force.

    Science.gov (United States)

    Höpfner, Johannes; Klein, Christopher; Wilhelm, Manfred

    2010-08-01

    Desalination of a sodium chloride solution is achieved by the incorporation of salt depleted water into an acrylic acid based hydrogel and the subsequent deswelling of the gel by mechanical force to gain water with a lower salt content. This is a new approach towards the problem of desalination of seawater that has, to the best of our knowledge, not been presented before. In a proof-of-principle experiment the salt content of a 10 g/L NaCl solution could be reduced by 35% in one cycle. The influence of main chemical parameters, e.g. degree of crosslinking, degree of neutralization and experimental parameters like particle size and salt concentration on the desalination process are examined. Possible optimum conditions for the desalination using a poly(acrylic acid) network are discussed and the construction of a simple apparatus for deswelling by mechanical force is described.

  20. Preparation, characterization, and antibacterial activity studies of silver-loaded poly(styrene-co-acrylic acid) nanocomposites.

    Science.gov (United States)

    Song, Cunfeng; Chang, Ying; Cheng, Ling; Xu, Yiting; Chen, Xiaoling; Zhang, Long; Zhong, Lina; Dai, Lizong

    2014-03-01

    A simple method for preparing a new type of stable antibacterial agent was presented. Monodisperse poly(styrene-co-acrylic acid) (PSA) nanospheres, serving as matrices, were synthesized via soap-free emulsion polymerization. Field-emission scanning electron microscopy micrographs indicated that PSA nanospheres have interesting surface microstructures and well-controlled particle size distributions. Silver-loaded poly(styrene-co-acrylic acid) (PSA/Ag-NPs) nanocomposites were prepared in situ through interfacial reduction of silver nitrate with sodium borohydride, and further characterized by transmission electron microscopy and X-ray diffraction. Their effects on antibacterial activity including inhibition zone, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bactericidal kinetics were evaluated. In the tests, PSA/Ag-NPs nanocomposites showed excellent antibacterial activity against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli. These nanocomposites are considered to have potential application in antibacterial coatings on biomedical devices to reduce nosocomial infection rates. PMID:24433897

  1. Synthesis, characterization, and swelling behaviors of salt-sensitive maize bran-poly(acrylic acid) superabsorbent hydrogel.

    Science.gov (United States)

    Zhang, Mingyue; Cheng, Zhiqiang; Zhao, Tianqi; Liu, Mengzhu; Hu, Meijuan; Li, Junfeng

    2014-09-01

    A novel composite hydrogel was prepared via UV irradiation copolymerization of acrylic acid and maize bran (MB) in the presence of composite initiator (2,2-dimethoxy-2-phenylacetophenone and ammonium persulfate) and cross-linker (N,N'-methylenebis(acrylamide)). Under the optimized conditions, maize bran-poly(acrylic acid) was obtained (2507 g g(-1) in distilled water and 658 g g(-1) in 0.9 wt % NaCl solution). Effects of granularity, salt concentration, and various cations and anions on water absorbency were investigated. It was found that swelling was extremely sensitive to the ionic strength and cation and anion type. Swelling kinetics and water diffusion mechanism in distilled water were also discussed. Moreover, the product showed excellent water retention capability under the condition of high temperature or high pressure. The salt sensitivity, good water absorbency, and excellent water retention capability of the hydrogels give this intelligentized polymer wide potential applications.

  2. Electron Beam Synthesis and Characterization of Acrylamide/Acrylic Acid Hydrogels Using Trimethylolpropane Trimethacrylate as Cross-Linker

    Directory of Open Access Journals (Sweden)

    Gabriela Craciun

    2016-01-01

    Full Text Available The purpose of the paper is to present the synthesis and characterization of hydrogels prepared by free-radical copolymerization of acrylamide and acrylic acid in aqueous solutions using potassium persulfate as initiator and trimethylolpropane trimethacrylate as cross-linker, via the radiation technique. The samples were subjected to electron beam treatment in the dose range of 2 to 4 kGy and the influence of the absorbed dose and amount of cross-linker on the swelling properties, diffusion coefficient, and network parameters of hydrogels was investigated. A possible reaction mechanism for acrylamide/acrylic acid/trimethylolpropane trimethacrylate hydrogels was also suggested. The structure and morphology of hydrogels were characterized by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy.

  3. Improvement in the behavior of bromelain coupled to pNIPAm polymers containing acrylamide or acrylic acid

    OpenAIRE

    Rubab Mahmood

    2014-01-01

    Bromelain was coupled to N-isopropyl acrylamide (NIPAm)polymers, synthesized using NIPAm and various concentrations of acrylamide (Ac) or acrylic acid (AAc). Incorporation of Ac/AAcinto the polymer increased the LCST (lower critical solutiontemperature) in a concentration dependent manner but AAc wasmore effective in this regard; the LCST rose to 40°C when 6 percent AAc was used. Incorporation of Ac/AAc increased the coupling of enzyme to the polymer and the η (effectiveness factor) o...

  4. Rapid 3D Patterning of Poly(acrylic acid) Ionic Hydrogel for Miniature pH Sensors.

    Science.gov (United States)

    Yin, Ming-Jie; Yao, Mian; Gao, Shaorui; Zhang, A Ping; Tam, Hwa-Yaw; Wai, Ping-Kong A

    2016-02-17

    Poly(acrylic acid) (PAA), as a highly ionic conductive hydrogel, can reversibly swell/deswell according to the surrounding pH conditions. An optical maskless -stereolithography technology is presented to rapidly 3D pattern PAA for device fabrication. A highly sensitive miniature pH sensor is demonstrated by in situ printing of periodic PAA micropads on a tapered optical microfiber. PMID:26643765

  5. Obtention and characterization of acrylic acid-i-polyethylene organometallic copolymers with Mo, Fe, Co, Zn, and Ni

    International Nuclear Information System (INIS)

    In this study a graft acrylic acid (AA) in low density polyethylene (PEBD) copolymers were prepared, using as reaction initiator, gamma radiation at different doses. These copolymers were coordinated with molybdenum, cobalt, iron, zinc and nickel. the obtained polymeric materials were characterized by conventional analysis techniques. It was studied the measurement parameter variation of the positron annihilation when they inter activated with this type of materials and so obtaining information about microstructure of these polymers. (Author)

  6. Tuning of thermally induced sol-to-gel transitions of moderately concentrated aqueous solutions of doubly thermosensitive hydrophilic diblock copolymers poly(methoxytri(ethylene glycol) acrylate)-b-poly(ethoxydi(ethylene glycol) acrylate-co-acrylic acid).

    Science.gov (United States)

    Jin, Naixiong; Zhang, Hao; Jin, Shi; Dadmun, Mark D; Zhao, Bin

    2012-03-15

    We report in this article a method to tune the sol-to-gel transitions of moderately concentrated aqueous solutions of doubly thermosensitive hydrophilic diblock copolymers that consist of two blocks exhibiting distinct lower critical solution temperatures (LCSTs) in water. A small amount of weak acid groups is statistically incorporated into the lower LCST block so that its LCST can be tuned by varying solution pH. Well-defined diblock copolymers, poly(methoxytri(ethylene glycol) acrylate)-b-poly(ethoxydi(ethylene glycol) acrylate-co-acrylic acid) (PTEGMA-b-P(DEGEA-co-AA)), were prepared by reversible addition-fragmentation chain transfer polymerization and postpolymerization modification. PTEGMA and PDEGEA are thermosensitive water-soluble polymers with LCSTs of 58 and 9 °C, respectively, in water. A 25 wt % aqueous solution of PTEGMA-b-P(DEGEA-co-AA) with a molar ratio of DEGEA to AA units of 100:5.2 at pH = 3.24 underwent multiple phase transitions upon heating, from a clear, free-flowing liquid (sol-to-gel transition temperature (T(sol-gel)) shifted to higher values, while the gel-to-sol transition (T(gel-sol)) and the clouding temperature (T(clouding)) of the sample remained essentially the same. These transitions and the tunability of T(sol-gel) originated from the thermosensitive properties of two blocks of the diblock copolymer and the pH dependence of the LCST of P(DEGEA-co-AA), which were confirmed by dynamic light scattering and differential scanning calorimetry studies. Using the vial inversion test method, we mapped out the C-shaped sol-gel phase diagrams of the diblock copolymer in aqueous buffers in the moderate concentration range at three different pH values (3.24, 5.58, and 5.82, all measured at ~0 °C). While the upper temperature boundaries overlapped, the lower temperature boundary shifted upward and the critical gelation concentration increased with the increase of pH. The AA content in PTEGMA-b-P(DEGEA-co-AA) was found to have a significant

  7. Graft copolymerization of N-maleoyl-N-phthaloyl-chitosan (MAPHCS) and acrylic acid via γ-ray irradiation

    International Nuclear Information System (INIS)

    Chitosan is a well-known abundant natural polymer with good biodegradability, biocompatibility and bioactivity. But its insolubility in common organic solvents of chitosan have hindered its utilization and basic research. N-maleoyl-N-phthaloyl-chitosan (MAPHCS), soluble in DMF or DMSO, was synthesized and characterized by Fourier transform infrared spectra analysis (FT-IR) and 1H-NMR. The graft copolymerization of acrylic acid onto chitosan was carried out with N-maleoyl-N-phthaloyl-chitosan as intermediate in homogeneous system and initiated by γ-irradiation. The double bond of MAPHCS may be the grafting site because the grafting field was much higher than that of the graft copolymerization of acrylic acid and phthaloylchitosan via γ-ray irradiation. The chemical structure of the graft copolymer was characterized by FT-IR and 1H-NMR. As indicated in FTIR spectra, the evidence of the stronger absorbance at 2800-3000 cm-1 for C-H and at 1720 cm-1 for carboxyl group implied significantly the successful introduction of the poly (acrylic acid) on the chitosan chain. Differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) were also used to characterize the copolymer. Effects of synthesis variables on the graft copolymerization were studied in light of the grafting percentage. The grafting percentage increased with the dose at lower doses, and then decreased. The maximum grafting percentage was up to 132%. (authors)

  8. Optical spectroscopy of Nd{sup 3+} ions in poly(acrylic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Ramos-Lara, F [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 Mexico, DF (Mexico); C, A Lira [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 Mexico, DF (Mexico); Ramirez, M O [Departamento de Fisica de Materiales, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Flores, M [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 Mexico, DF (Mexico); Arroyo, R [Departamento de Quimica, Universidad Autonoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 Mexico, DF (Mexico); Caldino, U [Departamento de Fisica de Materiales, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)

    2006-08-30

    Nd{sup 3+} dissolved in solid poly(acrylic acid) was synthesized by polymerization of the monomer partially neutralized with neodymium hydroxide in aqueous solution. The monomer modification and the coordination of ligands to Nd{sup 3+} were confirmed by {sup 1}H NMR spectroscopy. The measured oscillator strengths for transitions from the ground state to the main excited state manifolds compared favourably with calculated electric dipole oscillator strengths. The spontaneous emission rates, the fluorescence branching ratios and the stimulated emission cross sections of the {sup 4}F{sub 3/2} {yields} {sup 4}I{sub 9/2}, {sup 4}F{sub 3/2} {yields} {sup 4}I{sub 11/2} and {sup 4}F{sub 3/2} {yields} {sup 4}I{sub 13/2} transitions, as well as the radiative lifetime and the quantum efficiency of the {sup 4}F{sub 3/2} emitting level, were determined.

  9. Antimicrobial activity of poly(vinyl alcohol)-poly(acrylic acid) electrospun nanofibers.

    Science.gov (United States)

    Santiago-Morales, Javier; Amariei, Georgiana; Letón, Pedro; Rosal, Roberto

    2016-10-01

    Electrospun nanofibers were prepared from blends of poly(acrylic acid) (PAA) and poly(vinyl alcohol) (PVA). The fibers were stabilized by heat curing at 140°C via anhydride and ketone formation and crosslinking esterification. The antimicrobial effect was assessed using strains of Escherichia coli and Staphylococcus aureus by tracking their capacity to form colonies and their metabolic impairment upon contact with PAA/PVA membranes. Membranes containing >35wt.% PAA displayed significant antibacterial activity, which was particularly high for the gram-positive S. aureus. All membranes were negatively charged, with surface ζ-potential in the (-34.5)-(-45.6)mV range, but the electrostatic interaction with the negatively charged cells was not the reason for the antimicrobial effect. Neither pH reduction nor the passing of non-crosslinked polymers to the solution affected microbial growth. The antibacterial activity was attributed to the chelation of the divalent cations stabilizing the outer cell membrane. The effect on gram-positive bacteria was attributed to the destabilization of the peptidoglycan layer. The sequestration of divalent cations was demonstrated with experiments in which calcium and a chelating agent were added to the cultures in contact with membranes. The damage to bacterial cells was tracked by measuring their surface charge and the evolution of intracellular calcium during the early stages after contact with PAA/PVA membranes. PMID:27318959

  10. Potassium fulvate as co-interpenetrating agent during graft polymerization of acrylic acid from cellulose.

    Science.gov (United States)

    Ghazy, Mohamed B M; El-Hai, Farag Abd; Mohamed, Magdy F; Essawy, Hisham A

    2016-10-01

    Grafting polymerization of acrylic acid onto cellulose in presence of potassium fulvate (KF) as a co-interpenetrating agent results enhanced water sorption compared to materials prepared similarly in its absence. The insertion of potassium fulvate (KF) did not affect the grafting process and is thought to proceed in parallel to the graft polymerization via intensive polycondensation reactions of its function groups (-COOH and OH) with COOH of the monomer and OH groups of cellulose. The combination of graft copolymerization and polycondensation reactions is assumed to produce interpenetrating network structure. Fourier transform infrared (FTIR) confirmed successful incorporation within the network structure which is an evidence for formation of interpenetrating network. The obtained structures showed homogeneous uniform surface as revealed by scanning electron microscopy (SEM). The obtained superabsorbent possessed high water absorbency 422 and 48.8g/g in distilled water and saline (0.9wt.% NaCl solution), respectively, and enhanced water retention even at elevated temperatures as revealed by thermogravimetric analysis (TGA). This could be explained by the high content of hydrophilic groups. The new superabsorbents proved to be efficient devices for controlled release of fertilizers which expands their use in agricultural applications. PMID:27370745

  11. Syntheses and Crystal Structures of Two Complexes with 3-(3-Pyridyl)acrylic Acid

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The reaction of 3-(3-pyridyl)acrylic acid (H(3-PYA)) with Co(NO3)2·6H2O or Complex 1 crystallizes in monoclinic, space group C2/c with a = 9.9473(12), b = 13.7227(16), c =14.7376(18) (A), β = 99.043(2)°, V = 1986.7(4) (A)3, Z = 4, Dc = 1.549 g/cm3, μ = 0.921 mm 1, F(000)= 964, R = 0.0786 and wR = 0.1443. Six types of hydrogen bonds and π-π packing interactions molecular architecture. Complex 2 crystallizes in monoclinic, space group P21/n with a =11.3630(16), b = 7.0346(10), c = 12.1365(18) (A), β = 112.545(3)°, V = 896.0(2) (A)3, Z = 2, Dc =1.997 g/cm3,μ = 0.785 mm-1, F(000) = 438, R = 0.0787 and wR = 0.1550. The discrete entity Mn(Ⅱ)(3-PYD)2(H2O)4 is extended into a 3-D supramolecular architecture by four kinds of hydrogen bonds.

  12. Removal of cationic dyes by poly(acrylamide-co-acrylic acid) hydrogels in aqueous solutions

    International Nuclear Information System (INIS)

    Poly(acrylamide-co-acrylic acid (poly(AAm-co-AAc)) hydrogels prepared by irradiating with γ-radiation were used in experiments on swelling, diffusion, and uptake of some cationic dyes such as Safranine-O (SO) and Magenta (M). Poly(AAm-co-AAc) hydrogels irradiated at 8.0 kGy have been used for swelling and diffusion studies in water and cationic dye solutions. The maximum swellings in water, and SO, and M solutions observed are 2700%, 3500%, and 4000%, respectively. Diffusions of water and cationic dyes within hydrogels have been found to be non-Fickian in character. Adsorption of the cationic dyes onto poly(AAm-co-AAc) hydrogels is studied by the batch adsorption technique. The adsorption type was found Langmuir type in the Giles classification system. The moles of adsorbed dye for SO and M per repeating unit in hydrogel (binding ratio, r) have been calculated as 3834x10-6 and 1323x10-6, respectively. These results show that poly(AAm-co-AAc) hydrogels can be used as adsorbent for water pollutants such as cationic dyes

  13. Dynamic wettability and contact angles of poly(vinylidene fluoride nanofiber membranes grafted with acrylic acid

    Directory of Open Access Journals (Sweden)

    2010-09-01

    Full Text Available Wettability has been recognized as one of the most important properties of fibrous materials for both fundamental and practical applications. In this study, the plasma induced grafting of acrylic acid (AAc was applied to improve the wettability of the electrospun poly(vinylidene fluoride (PVDF nanofiber membranes. The diameter and chemical structure of the modified PVDF nanofibers were characterized by scanning electron microscopy (SEM and Fourier transform infrared (FTIR. Nitrogen adsorption based on BET (Brunauer, Emmett and Teller principle was employed to measure the specific surface areas and porosities of the modified nanofiber membrances. The contact angles of the modified membrane were evaluated by drop shape analysis (DSA and the modified Washburn method. The dependence of contact angles on specific surface area and porosity was also discussed in this paper. Water adsorptions were used to evaluate the dynamic wetting behavior of the grafted membranes by a dynamic adsorption apparatus (CDCA100-F. The experimental results revealed that the wettablity of the modified PVDF membrane was significantly affected by both surface and porous contact angles.

  14. Cellulose nanocrystal-filled poly(acrylic acid) nanocomposite fibrous membranes

    Science.gov (United States)

    Lu, Ping; Hsieh, You-Lo

    2009-10-01

    Nanocomposite fibrous membranes have been fabricated by electrospinning cellulose nanocrystal (CNC)-loaded poly(acrylic acid) (PAA) ethanol mixtures. Incorporating CNC in PAA significantly reduced fiber diameters and improved fiber uniformity. The average diameters of the as-spun nanocomposite fibers were significantly reduced from 349 nm to 162 nm, 141 nm, 90 nm and 69 nm at 5%, 10%, 15% and 20% CNC loading (by weight of a constant 4% PAA solution), respectively. CNC was well dispersed in the fibers as isolated rods oriented along the fiber axis and as spheres in the PAA matrix. The Young modulus and stress of the PAA/CNC nanocomposite fibers were significantly improved with increasing CNC loadings by up to 35-fold and 16-fold, respectively. Heat-induced esterification between the CNC surface hydroxyls and PAA carboxyl groups produced covalent crosslinks at the CNC-PAA interfaces, rendering the nanocomposite fibrous membranes insoluble in water, more thermally stable and far more superior in tensile strength. With 20% CNC, the crosslinked nanocomposite fibrous membrane exhibited a very impressive 77-fold increase in modulus and 58-fold increase in stress.

  15. Cellulose nanocrystal-filled poly(acrylic acid) nanocomposite fibrous membranes

    International Nuclear Information System (INIS)

    Nanocomposite fibrous membranes have been fabricated by electrospinning cellulose nanocrystal (CNC)-loaded poly(acrylic acid) (PAA) ethanol mixtures. Incorporating CNC in PAA significantly reduced fiber diameters and improved fiber uniformity. The average diameters of the as-spun nanocomposite fibers were significantly reduced from 349 nm to 162 nm, 141 nm, 90 nm and 69 nm at 5%, 10%, 15% and 20% CNC loading (by weight of a constant 4% PAA solution), respectively. CNC was well dispersed in the fibers as isolated rods oriented along the fiber axis and as spheres in the PAA matrix. The Young modulus and stress of the PAA/CNC nanocomposite fibers were significantly improved with increasing CNC loadings by up to 35-fold and 16-fold, respectively. Heat-induced esterification between the CNC surface hydroxyls and PAA carboxyl groups produced covalent crosslinks at the CNC-PAA interfaces, rendering the nanocomposite fibrous membranes insoluble in water, more thermally stable and far more superior in tensile strength. With 20% CNC, the crosslinked nanocomposite fibrous membrane exhibited a very impressive 77-fold increase in modulus and 58-fold increase in stress.

  16. Poly(acrylic acid) coating induced 2-line ferrihydrite nanoparticle transport in saturated porous media

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Aishuang [Princeton University, Chemical and Biological Engineering Department (United States); Yan, Weile [Texas Tech University, Civil and Environmental Engineering (United States); Koel, Bruce E., E-mail: bkoel@princeton.edu [Princeton University, Chemical and Biological Engineering Department (United States); Jaffe, Peter R., E-mail: jaffe@princeton.edu [Princeton University, Civil and Environmental Engineering Department (United States)

    2013-07-15

    Iron oxide and iron nanoparticles (NPs) have been used effectively for environmental remediation, but are limited in their applications by strong retention in groundwater-saturated porous media. For example, delivery of NPs to large groundwater reservoirs would require large numbers of injection wells. To address this problem, we have explored polymer coatings as a surface engineering strategy to enhance transport of oxide nanoparticles in porous media. We report here on our studies of 2-line ferrihydrite NPs and the influence of poly (acrylic acid) (PAA) polymer coatings on the colloidal stability and transport in natural sand-packed column tests simulating flow in groundwater-saturated porous media. Measurements were also made of zeta potential, hydrodynamic diameter, and polymer adsorption and desorption properties. The coated NPs have a diameter range of 30-500 nm. We found that NP transport was improved by PAA coating and that the transport properties could be tuned by adjusting the polymer concentration. Our results demonstrate that a high stability of oxide particles and improved transport can be achieved in groundwater-saturated porous media by introducing negatively charged polyelectrolytes and optimizing polymer concentrations.

  17. Synthesis and characterization of polycaprolactone/acrylic acid (PCL/AA) hydrogel for controlled drug delivery

    Indian Academy of Sciences (India)

    Nazar Mohammad Ranjha; Jahanzeb Mudassir; Sajid Majeed

    2011-12-01

    In the present work biodegradable pH-sensitive polycaprolactone/acrylic acid (PCL/AA) hydrogels have been developed using ethylene glycol dimethacrylate (EGDMA) as a cross-linker and benzoyl peroxide as initiator. For these prepared hydrogels swelling studies, sol–gel fraction analysis and porosity measurements were performed. Results show that swelling of the hydrogels decreases on increasing the concentration of PCL and EGDMA, however swelling of hydrogels increases on increasing the concentration of AA. Results of sol–gel fraction analysis show that gel fraction increases on increasing concentration of monomer AA, polymer PCL as well as cross-linker EGDMA. As far as porosity is concerned, it increases on increasing the concentration of AA and PCL while porosity decreases on increasing the concentration of EGDMA. Hydrogels were characterized by measuring diffusion coefficient () and equilibrium water content (EWC). Network formation, morphology and crystallinity of PCL/AA hydrogels were investigated using FTIR, SEM and XRD, respectively. Tramadol hydrochloride was loaded as model drug and its release pattern was analysed using various kinetic models like zero order, first order, Higuchi and Peppas. Results indicated that most of the samples followed non-Fickian release mechanism.

  18. Synthesis and characterization of zinc chloride containing poly(acrylic acid) hydrogel by gamma irradiation

    International Nuclear Information System (INIS)

    In this study, the characterization of zinc chloride incorporated into a poly(acrylic acid) (PAAc) hydrogel prepared by gamma-ray irradiation was investigated. Zinc chloride powder with different concentrations was dissolved in the PAAc solution, and it was crosslinked with gamma-ray irradiation. The effects of various parameters such as zinc ion concentration and irradiation doses on characteristics of the hydrogel formed were investigated in detail for obtaining an antibacterial wound dressing. In addition, the gel content, pH-sensitive (pH 4 or 7) swelling ratio, and UV–vis absorption spectra of the zinc particles in the hydrogels were characterized. Moreover, antibacterial properties of these new materials against Staphylococcus aureus and Escherichia coli strains were observed on solid growth media. The antibacterial tests indicated that the zinc chloride containing PAAc hydrogels have good antibacterial activity. - Highlights: • The characterization of zinc chloride containing PAA hydrogel was investigated. • The gel content increased with an increase in absorbed dose up to 75 kGy. • Finally, the zinc chloride based hydrogels have an antibacterial activity

  19. Preparation and properties of poly(acrylic acid) oligomer stabilized superparamagnetic ferrofluid.

    Science.gov (United States)

    Lin, Chia-Lung; Lee, Chia-Fen; Chiu, Wen-Yen

    2005-11-15

    Ferrofluids, which are stable dispersions of magnetic particles, behave as liquids that have strong magnetic properties. Nanoparticles of magnetite with a mean diameter of 10-15 nm, which are in the range of superparamagnetism, are usually prepared by the traditional method of co-precipitation from ferrous and ferric electrolyte solution. When diluted, the ferrofluid dispersions are not stable if anionic or cationic surfactants are used as the stabilizer. This work presents an efficient way to prepare a stable aqueous nanomagnetite dispersion. A stable ferrofluid containing Fe3O4 nanoparticles was synthesized via co-precipitation in the presence of poly(acrylic acid) oligomer. The mechanism, microstructure, and properties of the ferrofluid were investigated. The results indicate that the PAA oligomers promoted the nucleation and inhibited the growth of the magnetic iron oxide, and the average diameter of each individual Fe3O4 particle was smaller than 10 nm. In addition, the PAA oligomers provided both electrostatic and steric repulsion against particle aggregation, and the stability of dispersions could be controlled by adjusting the pH value of solution. A small amount of Fe2O3 was found in the nanoparticles but the superparamagnetic behavior of the nanoparticles was not affected. PMID:16009367

  20. Poly(acrylic acid) brushes pattern as a 3D functional biosensor surface for microchips

    Science.gov (United States)

    Wang, Yan-Mei; Cui, Yi; Cheng, Zhi-Qiang; Song, Lu-Sheng; Wang, Zhi-You; Han, Bao-Hang; Zhu, Jin-Song

    2013-02-01

    Poly(acrylic acid) (PAA) brushes, a novel three dimensional (3D) precursor layer of biosensor or protein microarrays, possess high protein loading level and low non-specific protein adsorption. In this article, we describe a simple and convenient way to fabricate 3D PAA brushes pattern by microcontact printing (μCP) and characterize it with FT-IR and optical microscopy. The carboxyl groups of PAA brushes can be applied to covalently immobilize protein for immunoassay. Thriving 3D space made by patterning PAA brushes thin film is available to enhance protein immobilization, which is confirmed by measuring model protein interaction between human immunoglobulin G (H-IgG) and goat anti-H-IgG (G-H-IgG) with fluorescence microscopy and surface plasmon resonance imaging (SPRi). As expected, the SPRi signals of H-IgG coating on 3D PAA brushes pattern and further measuring specific binding with G-H-IgG are all larger than that of 3D PAA brushes without pattern and 2D bare gold surface. We further revealed that this surface can be used for high-throughput screening and clinical diagnosis by label-free assaying of Hepatitis-B-Virus surface antibody (HBsAb) with Hepatitis-B-Virus surface antigen (HBsAg) concentration array chip. The linearity range for HBsAb assay is wider than that of conventional ELISA method.

  1. A study on the effect of the concentration of N,N-methylenebisacrylamide and acrylic acid toward the properties of Dioscorea hispida-starch-based hydrogel

    Science.gov (United States)

    Ashri, Airul; Lazim, Azwan

    2014-09-01

    The research investigated the effects of acrylic acid (monomer) and N,N,-methylenebisacrylamide, MBA (crosslinker) toward the percentage of gel content, swelling ratio and ionic strength of a starch-based hydrogel. Starch grafted on poly (sodium acrylate), St-g-PAANa hydrogel was prepared by incorporating starch extracted from Dioscorea hispida in NaOH/aqueous solution using different composition of acrylic acid (AA) and N,N-methylenebisacrylamide (MBA) in the presence of potassium persulfate (KPS) as chemical initiator. The highest gel content was observed at 1:30 ratio of starch to AA and 0.10 M of MBA. Results showed the highest swelling ratio was observed at 1:15 ratio of starch to acrylic acid and 0.02 M of MBA solution. The same results also gave the highest swelling ratio for the ionic strength study. The FTIR analysis was also conducted in order to confirm the grafting of AA onto starch backbone.

  2. Chelation in Metal Intoxication XLVI:Synthesis of Some α-Mercapto-β-Substituted Aryl Acrylic Acids and Their In vitro Cadmium Chelating Ability

    Institute of Scientific and Technical Information of China (English)

    MADHUMITA CHATTERJEE; VINOD K. DWIVEDI; KIRTI KHANDEKAR; SUSHIL K. TANDON

    2004-01-01

    Objective To synthesize some new α-mercapto-β-substituted aryl acrylic acids, characterize them and investigate their in vitro cadmium chelating ability. Methods Six α-mercapto-β-substituted aryl acrylic acids were prepared by the alkaline hydrolysis of 5-(aryl methylene)rhodanines, obtained from the condensation of substituted aldehydes and rhodanine following the reported procedure. The new compounds were characterized by elemental analysis, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. The liver and kidney from cadmium chloride pre-administered rats were homogenized and their nuclear mitochondrial fraction (NMF) and supernatant cytosol fraction (SCF) were separated. A measured volume of each fraction was dialyzed separately using "dialysis sack" against buffered-KCl medium containing a compound in the final concentration of 1×10-3 mol/L for 3 h at 37℃C. The whole content of "sack" was subjected to cadmiumestimation following digestion with conc. Nitric acid was detected using flame atomic absorption spectrometer. Results The in vitro screening showed that α-mercapto-β-(p-methoxyphenyl)acrylic acid (compound 2) and α-mercapto-β-(m-methoxy, p-hydroxyphenyl) acrylic acid (compound 4) were more effective than α-mercapto-β-thienyl acrylic acid (compound 1) and α-mercapto-β-(p-dimethylaminophenyl) acrylic acid (compound 3) in mobilizing cadmium as their dialyzable chelates. The presence of a methoxy group on the phenyl moiety (compounds 2 and 4) increases the metal chelating ability of mercapto acrylic acids. Conclusions Compounds 2 and 4 seem to have accessibility to the cellular system and capability of chelating-out the intracellularly bound cadmium.

  3. Acetic and Acrylic Acid Molecular Imprinted Model Silicone Hydrogel Materials for Ciprofloxacin-HCl Delivery

    Directory of Open Access Journals (Sweden)

    Lyndon Jones

    2012-01-01

    Full Text Available Contact lenses, as an alternative drug delivery vehicle for the eye compared to eye drops, are desirable due to potential advantages in dosing regimen, bioavailability and patient tolerance/compliance. The challenge has been to engineer and develop these materials to sustain drug delivery to the eye for a long period of time. In this study, model silicone hydrogel materials were created using a molecular imprinting strategy to deliver the antibiotic ciprofloxacin. Acetic and acrylic acid were used as the functional monomers, to interact with the ciprofloxacin template to efficiently create recognition cavities within the final polymerized material. Synthesized materials were loaded with 9.06 mM, 0.10 mM and 0.025 mM solutions of ciprofloxacin, and the release of ciprofloxacin into an artificial tear solution was monitored over time. The materials were shown to release for periods varying from 3 to 14 days, dependent on the loading solution, functional monomer concentration and functional monomer:template ratio, with materials with greater monomer:template ratio (8:1 and 16:1 imprinted tending to release for longer periods of time. Materials with a lower monomer:template ratio (4:1 imprinted tended to release comparatively greater amounts of ciprofloxacin into solution, but the release was somewhat shorter. The total amount of drug released from the imprinted materials was sufficient to reach levels relevant to inhibit the growth of common ocular isolates of bacteria. This work is one of the first to demonstrate the feasibility of molecular imprinting in model silicone hydrogel-type materials.

  4. Fracture Mechanisms of Layer-By-Layer Polyurethane/Poly(Acrylic Acid) Nanocomposite

    Science.gov (United States)

    Kheng, Eugene R.

    A layer-by-layer(LBL) manufactured material is examined in detail in this thesis. Improvements are made to the method of its manufacture. Efforts are made to understand its fracture mechanisms and take advantage of these fracture mechanisms in the absorption of impact energy. A novel series of experiments has been performed on LBL manufactured thin films to demonstrate their unique fracture mechanisms. Polyurethane/Poly(Acrylic Acid) (PU/PAA) and PU/PAA/(PU/Clay)5 nanocomposite films readily undergo Interlaminar mode II fracture, because of the relatively weak elctrostatic bonds between monolayers. Tensile tests performed while under observation by a scanning electron microscope demonstrate the tendency of these nanocomposite films to undergo interlaminar mode II fracture even when loads are applied in the plane of nanocomposite film. It is concluded that these mechanisms of energy dissipation are responsible for the enhanced toughness of these films when used as layers between glass blocks in the prevention of impact damage to the glass. A novel automated manufacturing facility has been designed and built to deposit large sheets of Layer-by-Layer nanocomposite film. These large sheets are incorporated into a borosillicate glass composite in order to compare the ballistic characteristics of LBL PU based nanocomposite films to a single cast layer of polyurethane. It is demonstrated that shear fracture is the mode of failure in the blocks containing the nanocomposite film. The shear fracture surface in the nanocomposite after it has undergone a ballistic impact is characterized. Additional experiments are performed to characterize the interlaminar fracture stresses and toughnesses of the nanocomposite LBL layers, to assist in the implementation of a numerical crack band model that describes the nanocomposite film. The computational model predicts the failure of the ballistic nanocomposite samples, and the predicted V50 velocity is found to be in good agreement with

  5. Hydrophobically Modified Polyelectrolytes: V. Interaction of Fluorocarbon Modified Poly (acrylic acid) with Various Added Surfactants

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Hui(周晖); SONG,Guo-Qaiang(宋国强); GUO,Jin-Feng(郭金峰); ZHANG,Yun-xiang (章云祥); DIEING,Reinhold; MA,Lian(马莲); HAEUSSLING,Lukas

    2001-01-01

    The interactions between fiuorocarbon-medified pol(sodium acrylate) and various kinds of added surfactant have been studied by means of viscometric measurement. Association behavior was found in both hydrogenated and fluorinated anionic, nonionic and cationic surfactants. Among them, the interactions between fluorocarbon-modified poly ( sodium acrylate) and cationic surfactants are the strongest, owing to the cooperation of both electrostatic attractions and hydrophobic associations. The anionic surfactants have the weakest effects on the solution properties because of the existence of unfavorable electrostatic repulsion. The hydrophobic interactions between copolymers and fluorinated surfactants are much stronger than those between copolymers and hydrogenated surfactants.

  6. SYNTHESIS AND IN VITRO CHARACTERIZATION OF HYDROXYPROPYL METHYLCELLULOSE-GRAFT-POLY (ACRYLIC ACID/2-ACRYLAMIDO-2-METHYL-1-PROPANESULFONIC ACID) POLYMERIC NETWORK FOR CONTROLLED RELEASE OF CAPTOPRIL.

    Science.gov (United States)

    Furqan Muhammad, Iqbal; Mahmood, Ahmad; Aysha, Rashid

    2016-01-01

    A super-absorbent hydrogel was developed by crosslinking of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and acrylic acid with hydroxypropyl methylcellulose (HPMC) for controlled release drug delivery of captopril, a well known antihypertensive drug. Acrylic acid and AMPS were polymerized and crosslinked with HPMC by free radical polymerization, a widely used chemical crosslinking method. N,N'-methylenebisacrylamide (MBA) and potassium persulfate (KPS) were added as cross-linker and initiator, respectively. The hydrogel formulation was loaded with captopril (as model drug). The concentration of captopril was monitored at 205 nm using UV spectrophotometer. Equilibrium swelling ratio was determined at pH 2, 4.5 and 7.4 to evaluate the pH responsiveness of the formed hydrogel. The super-absorbent hydrogels were evaluated by FTIR, SEM, XRD, and thermal analysis (DSC and TGA). The formation of new copolymeric network was determined by FTIR, XRD, TGA and DSC analysis. The hydrogel formulations with acrylic acid and AMPS ratio of 4: 1 and lower amounts of crosslinker had shown maximum swelling. Moreover, higher release rate of captopril was observed at pH 7.4 than at pH 2, because of more swelling capacity of copolymer with increasing pH of the aqueous medium. The present research work confirms the development of a stable hydrogel comprising of HPMC with acrylic acid and AMPS. The prepared hydrogels exhibited pH sensitive behav-ior. This superabsorbent composite prepared could be a successful drug carrier for treating hypertension. PMID:27008813

  7. SYNTHESIS OF POLY(DIVINYLBENZENE-co-ACRYLIC ACID) HOLLOW MICROSPHERES WITH GOLD NANOPARTICLES ON THE INTERIOR SURFACE

    Institute of Scientific and Technical Information of China (English)

    Wei Liu; Xin-lin Yang; Xu-gang He

    2009-01-01

    Poly(divinylbenzene-co-acrylic acid) (poly(DVB-co-AA)) hollow microspheres with gold nanoparticles on the interior surfaces were prepared from the gold nanoparticles-coated poly(methacrylic acid) (PMAA@Au@poly(DVB-co-AA)) core-shell microspheres by removal of the PMAA core in water.Au nanoparticles-coated PMAA microspheres were afforded by the in-situ reduction of gold trichloride with PMAA microsphere as stabilizer via the interaction between carboxylic acid groups and Au nanoparticles.Gold nanoparticles-coated (PMAA@Au@poly(DVB-co-AA)) microspheres were formed during the distillation precipitation copolymerization of divinylbenzene and acrylic acid in acetonitrile with Au-coated PMAA microspheres as seeds.The thickness of the poly(DVB-co-AA) shell-layer was controlled by the amount of the solvent distilled off the polymerization system.The PMAA microspheres,Au nanoparticles-coated PMAA microspberes,core-shell microspheres,and hollow microspheres with Au nanoparticles on the interior surfaces were studied by transmission electron microscopy and scanning electron microscopy.The stabilization to L-cysteine and the preliminary catalytic property of the Au nanoparticles on the inner surface of hollow poly(DVB-co-AA) microspheres were investigated.

  8. Advances in the Research and Development of Acrylic Acid Production from Biomass%从生物量生产丙烯酸的研究和开发进展

    Institute of Scientific and Technical Information of China (English)

    许晓波; 林建平; 岑沛霖

    2006-01-01

    The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fermentation has been commercialized since longer times, the dehydration process of lactic acid is still under development because of its low yield. Further efforts should be made before this process became economically feasible.Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic engineering provides also a possibility to produce acrylic acid directly from biomass by fermentation.

  9. Synthesis of hollow silver spheres using poly-(styrene-methyl acrylic acid) as templates in the presence of sodium polyacrylate

    Science.gov (United States)

    Wang, Aili; Yin, Hengbo; Ge, Chen; Ren, Min; Liu, Yumin; Jiang, Tingshun

    2010-02-01

    Hollow silver spheres were successfully prepared by reducing AgNO 3 with ascorbic acid and using negatively charged poly-(styrene-methyl acrylic acid) (PSA) spheres as templates in the presence of sodium polyacrylate as a stabilizer. Firstly, silver cations adsorbed on the surface of PSA spheres via electrostatic attraction between the carboxyl groups and silver cations were reduced in situ by ascorbic acid. The silver nanoparticles deposited on the surface of PSA spheres served as seeds for the further growth of silver shells. After that, extra amount of AgNO 3 and ascorbic acid solutions were added to form PSA/Ag composites with thick silver shells. In order to obtain compact silver shells, the as-prepared PSA/Ag composites were heated at 150 °C for 3 h. Then hollow silver spheres were prepared by dissolving PSA templates with tetrahydrofuran.

  10. Characterization of interpenetrating networks of acrylic acid (AAc) and N-isopropylacrylamide (NIPAAm) synthesized by ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Adem, E. [Departamento de Fisica Experimental, Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico DF 04510 (Mexico); Burillo, G. [Departamento de Quimica de Radiaciones y Radioquimica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico DF 04510 (Mexico)], E-mail: burillo@nucleares.unam.mx; Bucio, E. [Departamento de Quimica de Radiaciones y Radioquimica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico DF 04510 (Mexico); Magana, C. [Departamento de Fisica Experimental, Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico DF 04510 (Mexico); Avalos-Borja, M. [Centro de Nanociencias y Nanotecnologia, Universidad Nacional Autonoma de Mexico, A. Postal 2681, Ensenada, B.C. 22800 (Mexico)

    2009-07-15

    Interpenetrating networks of poly(acrylic acid) (PAAc) and poly(N-isopropylacrylamide) (PNIPAAm) were synthesized in two consecutive steps utilizing ionizing radiation in the first step and chemical reaction in the second step. The first network of PAAc hydrogel was formed by ionizing radiation (gamma or electron beam). The secondary gel of PNIPAAm was synthesized directly within the primary gel of PAAc from an aqueous solution of N-isopropylacrylamide (NIPAAm) containing a crosslinking agent, accelerator and redox initiator. The interpenetrating networks (IPNs) were characterized morphologically by scanning electron microscopy (SEM), and their thermal behavior was analyzed by differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA)

  11. Preparation and characterization of acrylic acid-grafted poly (vinyl alcohol) hydrogel actuators using γ-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    An, Sung Jun; Lim, Youn Mook; Gwon, Hui Jeong; Kim, Yun Hye; Youn, Min Ho; Nho, Young Chang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Han, Dong Hyun; Kim, Chong Yeal [Dept. of Radiation Science AND Technology, Graduate School of Chonbuk National University, Jeonju (Korea, Republic of)

    2008-01-15

    Active polymer gels expand and contract in response to certain environmental stimuli, such as the application of an electric field or a change in the pH level of the surroundings. This ability to achieve large, reversible deformations with no external mechanical loading has generated much interest in the use of these gels as biomimetic actuators and artificial muscles. In this study, poly (vinyl alcohol)(PVA) grafted acrylic acid monomer (PVA-g-AAc) hydrogels were prepared by {sup 60}Co γ-ray irradiation and their properties such as degree of grafting and weight swelling in electrostimulation as an artificial muscle and actuator were investigated.

  12. New liner and reticular polyelectrolytes based an acetoacetic ehter and acrylic acid: synthesis, structure and stimulating sensitivity characteristics

    International Nuclear Information System (INIS)

    Novel linear and crosslinked poly-carbolytes based on acetoacetic ester and acrylic acid were synthesized for the first time via Michael addition reaction followed by the radical poly-mineralization. The structure and properties of polyelectrolytes were characterized by FTIR, Raman and NMR spectroscopy, TGA, DSC, GPC, viscosimetry, and potentiometric titration. Considerable influence of water content on the swelling rate of hydrogel was established. The swelling-deswelling properties of hydrogels were studied in water-organic solvent mixtures, electric and magnetic fields. (author)

  13. Preparation of pH-responsive ceramic composite membranes by grafting acrylic acid onto a-alumina membranes

    Institute of Scientific and Technical Information of China (English)

    YANG LianLi; ZHAO YiJiang; ZHOU ShouYong; LI MeiSheng; CHEN Yan; XING WeiHong

    2009-01-01

    A pH-responsive ceramic composite membrane was prepared by chemical graft polymerization of acrylic acid (AA) onto the KH-570 modified a-alumina membrane. The influence of monomer concentration on the gating characteristics of the pH-responsive membrane was investigated. The FT-IR spectrum, contact angle and water filtration rate of the membrane were measured. The monomer concentration was found to have a remarkable effect on the pH-response coefficient and the water filtration rate. In addition, the grafted membrane exhibited fast and reversible response to the pH change in the external solution.

  14. Effect of acid additives on graft copolymerization and water absorption of graft copolymers of cassava starch and acrylamide/acrylic acid

    International Nuclear Information System (INIS)

    Gelatinized cassava starch was radiation graft copolymerized with acrylamide or acrylic acid in the presence of sulfuric acid, nitric acid or maleic acid at a specific dose rate to a fixed total dose. Homopolymer or free copolymer was extracted by water to obtain the pure graft copolymer, which was subsequently saponified with 5% potassium hydroxide solution at room temperature for 90 min. The saponified graft copolymer was investigated for the effect of acid additives and water absorption. The addition of 2% maleic acid into the grafting reaction containing acrylamide-to-starch ratio of 2.5:1 can produce the superabsorbent copolymer having water absorption as high as 2,256 ± 25 g g-1. The effect of acid additive was explained. (author)

  15. Radiation Synthesis of Poly(N-Vinyl Pyrrolidone) Nanogels and Nanoscale Grafting of Poly(Acrylic Acid) from Cellulose

    International Nuclear Information System (INIS)

    Ionizing radiation has long been known to be a very useful tool for the preparation of nanogels. Although preparation is straightforward, the control of the sizes of nanogels has been a challenging issue. This report shows the results of our work on using radiation for the synthesis of PVP nanogels in the range of 40-200nm by making use of the principles of solution thermodynamics of aqueous polymer solutions. Nanoscale grafting of responsive polymers however has been of scientific and industrial importance due to fine control of the molecular weight and molecular weight distribution of grafted polymers. The second part of this report deals with the grafting of poly(acrylic acid) onto the surface of cellulose, thus imparting pH response to the substrate. The use of radiation as a constant source of radical generation and Reversible-Addition-Fragmentation-Chain transfer agents for the control of free radical polymerization provided a full control over the molecular weight and distribution of poly(acrylic acid) grafts on cellulose. (author)

  16. Poly (acrylic acid sodium) grafted carboxymethyl cellulose as a high performance polymer binder for silicon anode in lithium ion batteries.

    Science.gov (United States)

    Wei, Liangming; Chen, Changxin; Hou, Zhongyu; Wei, Hao

    2016-01-01

    The design of novel binder systems is required for the high capacity silicon (Si) anodes which usually undergo huge volume change during the charge/discharge cycling. Here, we introduce a poly (acrylic acid sodium)-grafted-carboxymethyl cellulose (NaPAA-g-CMC) copolymer as an excellent binder for Si anode in lithium ion batteries (LIBs). The NaPAA-g-CMC copolymer was prepared via a free radical graft polymerization method by using CMC and acrylic acid as precursors. Unlike the linear, one-dimensional binders, the NaPAA-g-CMC copolymer binder is expected to present multi-point interaction with Si surface, resulting in enhanced binding ability with Si particles as well as with the copper (Cu) current collectors, and building a stable solid electrolyte interface (SEI) layer on the Si surface. The NaPAA-g-CMC based Si anode shows much better cycle stability and higher coulombic efficiency than those made with the well-known linear polymeric binders such as CMC and NaPPA. PMID:26786315

  17. Preparation of acrylic acid-modified chitin improved by an experimental design and its application in absorbing toxic organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chao-Ming, E-mail: charming@mail.ksu.edu.tw [Department of Materials Engineering, Kun Shan University, Tainan, Taiwan (China); Chen, Lung-Chuan, E-mail: lcchen@mail.ksu.edu.tw [Department of Materials Engineering, Kun Shan University, Tainan, Taiwan (China); Yang, Hui-Chia, E-mail: yang.junkdna@gmail.com [Department of Environmental Engineering, Kun Shan University, Tainan, Taiwan (China); Li, Min-Hsing, E-mail: a1487561a@yahoo.com.tw [Department of Environmental Engineering, Kun Shan University, Tainan, Taiwan (China); Pan, Ting-Chung, E-mail: tcpan@mail.ksu.edu.tw [Department of Environmental Engineering, Kun Shan University, Tainan, Taiwan (China)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Acrylic acid-modified chitin. Black-Right-Pointing-Pointer Experimental design. Black-Right-Pointing-Pointer Graft copolymerization. Black-Right-Pointing-Pointer Adsorption of toxic organic compounds. Black-Right-Pointing-Pointer Very high adsorption capacity. - Abstract: Chitin grafted poly (acrylic acid) (chi-g-PAA) is synthesized and characterized as an adsorbent of toxic organic compounds. Chi-g-PAA copolymers are prepared using of ammonium cerium (IV) nitrate (Ce{sup 4+}) as the initiator. The highest grafting percentage of AA in chitin obtained using the traditional technique is 163.1%. A maximum grafting percentage of 230.6% is obtained using central composite design (CCD). Experimental results are consistent with theoretical calculations. The grafted copolymer is characterized by Fourier transform Infrared spectroscopy and solid state {sup 13}C NMR. A representative chi-g-AA copolymer is hydrolyzed to a type of sodium salt (chi-g-PANa) and used in the adsorption of malachite green (MG), methyl violet (MV), and paraquat (PQ) in aqueous. The monolayer adsorption capacities of these substances are 285.7, 357.1, and 322.6 mg/g-adsorbent, respectively. Thermodynamic calculations show that the adsorption of MG, MV, and PQ are more favored at diluted solutions. The high adsorption capacity of chi-g-PANa for toxic matter indicates its potential in the treatment of wastewater and emergency treatment of PQ-poisoned patients.

  18. Dye-sensitized solar cell with poly(acrylic acid-co-acrylonitrile)-based gel polymer electrolyte

    International Nuclear Information System (INIS)

    Highlights: ► A nontoxic, easily synthesized poly(acrylic acid-co-acrylonitrile) showed suitable transmittance for dye-sensitized solar cell. ► A cell with relatively large active area fabricated with this polymer material showed acceptable efficiency. ► The gel polymer matrix affected the charge recombination, I3− diffusion, double layer capacitance, and electron lifetime in the cell. - Abstract: A non-conducting, nontoxic poly(acrylic acid-co-acrylonitrile) (PAA) was prepared and used as a supporting matrix for the electrolyte of dye-sensitized solar cells (DSSCs). DSSCs of active area 0.80 cm × 1.10 cm fabricated with PAA, 0.5 M LiI, 0.05 M I2, 0.5 M 3-tert-butylpyridine, and 0.1 M 1-methyl-3-propylimidazolium iodide in 3-methoxypropionitrile solvent showed an average solar energy conversion efficiency of 1.61% under simulated sunlight illumination of 100 mW cm−2, AM 1.5. The effects of the gel polymer matrix on the electrochemical properties of DSSCs were studied using the electrochemical impedance spectroscopy. Relative to the non-gel reference cells, the results showed a decrease in charge recombination, ionic diffusion, and double layer capacitance and an increase in electron lifetime. These results could play an important role in determining the future direction for the development of high-performance gel polymer electrolytes.

  19. Improved Method for Preparation of Amidoxime Modified Poly(acrylonitrile-co-acrylic acid: Characterizations and Adsorption Case Study

    Directory of Open Access Journals (Sweden)

    Nur Amirah Mohd Zahri

    2015-07-01

    Full Text Available Redox polymerization of poly(acrylonitrile-co-acrylic acid (poly(AN-co-AA is performed at 40 °C under N2 gas by varying the ratio of acrylonitrile (AN and acrylic acid (AA in the feed. The yield production of poly(acrylonitrile (PAN is 73% and poly(AN-co-AA with a feed ratio of 93:7 is the highest yield (72%. The PAN and poly(AN-co-AA are further chemically modify with hydroxylamine hydrochloride. The FTIR spectroscopy is used to confirm the copolymerization of poly(AN-co-AA and chemical modification of poly(AN-co-AA. Elemental microanalysis shows that the overall trend percentage of carbon, hydrogen, and nitrogen for all feed ratios are slightly decreasing as the feed ratio of AA is increasing except for poly(AN-co-AA 93:7. The SEM images shows that spherical diameter of poly(AN-co-AA is smaller compared to the PAN and amidoxime (AO modified poly(AN-co-AA. The TGA (thermogravimetric analysis analysis reveals that the poly(AN-co-AA degrades at lower temperatures compared to the PAN but higher than AO modified poly(AN-co-AA. The case study adsorption test showed that the AO modified poly(AN-co-AA 93:7 had the highest percentage removal of Cd2+ and Pb2+.

  20. Preparation, characterization, and antibacterial activity studies of silver-loaded poly(styrene-co-acrylic acid) nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Song, Cunfeng [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Chang, Ying; Cheng, Ling; Xu, Yiting [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Chen, Xiaoling, E-mail: tinachen0628@163.com [Department of Endodontics, Xiamen Stomatology Hospital, Teaching Hospital of Fujian Medical University, Xiamen 361003 (China); Zhang, Long; Zhong, Lina [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Dai, Lizong, E-mail: lzdai@xmu.edu.cn [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China)

    2014-03-01

    A simple method for preparing a new type of stable antibacterial agent was presented. Monodisperse poly(styrene-co-acrylic acid) (PSA) nanospheres, serving as matrices, were synthesized via soap-free emulsion polymerization. Field-emission scanning electron microscopy micrographs indicated that PSA nanospheres have interesting surface microstructures and well-controlled particle size distributions. Silver-loaded poly(styrene-co-acrylic acid) (PSA/Ag-NPs) nanocomposites were prepared in situ through interfacial reduction of silver nitrate with sodium borohydride, and further characterized by transmission electron microscopy and X-ray diffraction. Their effects on antibacterial activity including inhibition zone, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bactericidal kinetics were evaluated. In the tests, PSA/Ag-NPs nanocomposites showed excellent antibacterial activity against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli. These nanocomposites are considered to have potential application in antibacterial coatings on biomedical devices to reduce nosocomial infection rates. - Highlights: • A new type of antibacterial agent (PSA/Ag-NPs nanocomposites) was synthesized. • The antibacterial activity against S. aureus and E. coli was studied. • Inhibition zone, MIC, MBC, and bactericidal kinetics were evaluated. • PSA/Ag-NPs nanocomposites showed excellent antibacterial activity.

  1. Controlled release of diclofenac sodium from pH-responsive carrageenan-g-poly(acrylic acid) superabsorbent hydrogel

    Indian Academy of Sciences (India)

    Hossein Hosseinzadeh

    2010-07-01

    In this paper, controlled release of diclofenac sodium (DS) from pH-sensitive carrageenan-gpoly(acrylic acid) superabsorbent hydrogels was investigated. The hydrogels were prepared by graft copolymerization of acrylic acid (AA) onto kappa-carrageenan, using ammonium persulfate (APS) as a free radical initiator in the presence of methylene bisacrylamide (MBA) as a crosslinker. Infrared spectroscopy was carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM). The synthesized hydrogels were subjected to equilibrium swelling studies in simulated gastric and intestinal fluids (SGF and SIF). Hydrogels containing drug DS, at different drug-to-polymer ratios, were prepared by direct adsorption method. The loading yield was found to depend on both the impregnation time and the amount of encapsulated drug. In vitro drug-release studies in different buffer solutions showed that the most important parameter affecting the drug-release behaviour of hydrogels is the pH of the solution. The mechanism involved in release was Fickian ( ≤ 0.43, = 0.348) and Super Case II kinetics ( > 1, = 1.231) at pH 1.2 and 7.4, respectively.

  2. The Chemical and Physical Properties of Poly( ε -caprolactone) Scaffolds Functionalised with Poly(vinyl phosphonic acid-co-acrylic acid)

    OpenAIRE

    Bassi, A. K.; Gough, J. E.; Zakikhani, M.; Downes, S

    2011-01-01

    There is a clinical need for a synthetic alternative to bone graft substitute (BGS) derived from demineralised bone matrix. We report the electrospinning of Poly(ε-caprolactone) (PCL) to form a 3-dimensional scaffold for use as a synthetic BGS. Additionally, we have used Poly(vinyl phosphonic acid-co-acrylic acid) (PVPA) to improve bone formation. Fibres were formed using a 10% w/v PCL/acetone solution. Infrared spectroscopy confirmed that the electrospinning process had no effect on the func...

  3. NaY zeolites modified by La~(3+) and Ba~(2+): the effect of synthesis details on surface structure and catalytic performance for lactic acid to acrylic acid

    Institute of Scientific and Technical Information of China (English)

    闫婕; 余定华; 李恒; 孙鹏; 黄和

    2010-01-01

    Modified NaY zeolites have been widely studied and the modification metal element is normally single, while few researches have been conducted on NaY zeolites modified by two kinds of metals. In our study, a series of La3+ and Ba2+ modified NaY zeolites were synthesized through different impregnation procedures. Lactic acid dehydration to acrylic acid was selected as a probe reaction to test the catalytic performance of these zeolites synthesized. The effects of synthesis details on their pore structures an...

  4. Physicochemical properties of poly(lactic acid-co-glycolic acid film modified via blending with poly(butyl acrylate-co-methyl methacrylate

    Directory of Open Access Journals (Sweden)

    Guoquan Zhu

    2013-01-01

    Full Text Available A series of poly(lactic acid-co-glycolic acid (PLGA/poly(butyl acrylate-co-methyl methacrylate (P(BA-co-MMA blend films with different P(BA-co-MMA mole contents were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the PLGAP(BA-co-MMA blend films were studied by scanning electron microscopy (SEM. Thermal, mechanical, and chemical properties of PLGAP(BA-co-MMA blend films were investigated by differential scanning calorimeter (DSC, thermogravimetric analysis (TGA, tensile tests, and surface contact angle tests. The introduction of P(BA-co-MMA could modify the properties of PLGA films.

  5. Characterization of pH-sensitive Poly (acrylic acid-co-N-vinyl-2-pyrrolidone) Hydrogels Prepared by Gamma Radiation

    Institute of Scientific and Technical Information of China (English)

    YANG Ming-cheng; HE Su-qin; LIU Wen-tao; SONG Hong-yan; ZHU Cheng-shen

    2007-01-01

    The pH-sensitive copolymer hydrogels were prepared with the monomers of acrylic acid and N-vinyl-2-pyrrolidone based on gamma radiation technique. The morphology of the hydrogels was monitored by using scanning electron microscope. The influence of absorbed dose, monomer compasition and concentration on the swelling ratio (SR) of the hydrogels were investigated in detail. The effect of pH and temperature of the swelling medium on the swelling behavior of the hydrogels were also examined. The results show that the SR of the copolymer hydrogels decreases with the monomer concentration and absorbed dose increasing. The copolymer hydrogels show a better pH-sensitive behavior. In alkaline solution, the SR of the hydrogels is much higher than in acid solution.

  6. Effect of time and temperature exposition in the crystallinity degree of sulfonated poly-(styrene acrylic acid) (PSAA-S)

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, G.W.; Becker, E.B.; Silva, L.; Naspolini, A.M.; Consenso, E.C.; Paula, M.M.S.; Fiori, M.A., E-mail: glau_bn@hotmail.co [University of Extreme South of Santa Catarina Criciuma, SC (Brazil). Dept. of Materials Engineering; Silveira, F.Z. [Federal University of Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. of Chemical Engineering

    2010-07-01

    Polymers with special properties have been increasingly applied in the development of technological devices. For example, polymeric materials with special electric properties, such as sulfonated poly-(styrene-acrylic acid) - PSAA-S, are of great interest for showing different conductivities depending on the environment where they are applied. The special properties of PSAA are obtained only after sulfonation step in acidic media. The present work aimed to evaluate the effect of time and temperature exposition in the crystallinity degree of PSAA-S, through a statistical experimental factorial planning. The samples of PSAA-S were submitted to FT-IR and DRX tests. The results showed that the temperature and the time of exposition are significant factors in the crystallinity degree of PSAA-S, considering that the crystal lattices created during the polymerization are damaged by the action of time and temperature at which the polymer is exposed. (author)

  7. Preparation and drug-loading properties of Fe{sub 3}O{sub 4}/Poly(styrene-co-acrylic acid) magnetic polymer nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wensheng [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China); Coordination Chemistry Institute, School of Chemistry and Chemical Engineering and Life Science, Chaohu University, Chaohu 238000 (China); Shen, Yuhua, E-mail: s_yuhua@163.com [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China); Xie, Anjian [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China); Zhang, Weiqiang [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China); Coordination Chemistry Institute, School of Chemistry and Chemical Engineering and Life Science, Chaohu University, Chaohu 238000 (China)

    2013-11-15

    Fe{sub 3}O{sub 4}/poly(styrene-co-acrylic acid) magnetic polymer nanocomposites were synthesized by the dispersion polymerization method using styrene as hard monomer, acrylic acid as functional monomer, Fe{sub 3}O{sub 4} nanoparticles modified with oleic acid as core, and poly(styrene-co-acrylic acid) as shell. Drug-loading properties of magnetic polymer nanocomposites with curcumin as a model drug were also studied. The results indicated that magnetic polymer nanocomposites with monodisperse were obtained, the particle size distribution was 50–120 nm, and the average size was about 100 nm. The contents of poly(styrene-co-acrylic acid) and Fe{sub 3}O{sub 4} nanoparticles in magnetic polymer nanocomposites were 74% and 24.7%, respectively. The drug-loading capacity and entrapment efficiency were 2.5% and 44.4%, respectively. The saturation magnetization of magnetic polymer nanocomposites at 300 K was 20.2 emu/g without coercivity and remanence. The as-prepared magnetic polymer nanocomposites have not only lots of functional carboxyl groups but also stronger magnetic response, which might have potential applications in drug carrier and targeted drug release.

  8. Synthesis of a proline-modified acrylic acid copolymer in supercritical CO2 for glass-ionomer dental cement applications.

    Science.gov (United States)

    Moshaverinia, Alireza; Roohpour, Nima; Darr, Jawwad A; Rehman, Ihtesham U

    2009-06-01

    Supercritical (sc-) fluids (such as sc-CO(2)) represent interesting media for the synthesis of polymers in dental and biomedical applications. Sc-CO(2) has several advantages for polymerization reactions in comparison to conventional organic solvents. It has several advantages in comparison to conventional polymerization solvents, such as enhanced kinetics, being less harmful to the environment and simplified solvent removal process. In our previous work, we synthesized poly(acrylic acid-co-itaconic acid-co-N-vinylpyrrolidone) (PAA-IA-NVP) terpolymers in a supercritical CO(2)/methanol mixture for applications in glass-ionomer dental cements. In this study, proline-containing acrylic acid copolymers were synthesized, in a supercritical CO(2) mixture or in water. Subsequently, the synthesized polymers were used in commercially available glass-ionomer cement formulations (Fuji IX commercial GIC). Mechanical strength (compressive strength (CS), diametral tensile strength (DTS) and biaxial flexural strength (BFS)) and handling properties (working and setting time) of the resulting modified cements were evaluated. It was found that the polymerization reaction in an sc-CO(2)/methanol mixture was significantly faster than the corresponding polymerization reaction in water and the purification procedures were simpler for the former. Furthermore, glass-ionomer cement samples made from the terpolymer prepared in sc-CO(2)/methanol exhibited higher CS and DTS and comparable BFS compared to the same polymer synthesized in water. The working properties of glass-ionomer formulations made in sc-CO(2)/methanol were comparable and better than the values of those for polymers synthesized in water. PMID:19269267

  9. SYNTHESIS OF SOAP-FREE ACRYLIC HYDROSOLS

    Institute of Scientific and Technical Information of China (English)

    Li Jia; Zong-hui Liu; De-qing Wei

    2002-01-01

    Poly(methyl methacrylate/ethyl acrylate/acrylic acid) hydrosols were prepared by employing soap-freepolymerization, and (acrylic acid/butyl acrylate) oligomer was used as the polymeric surfactant. The effect of reactioncondition on the morphology and particle size of the hydrosols was investigated. The minimum amount of acrylic acid in thehydrosols is 2%. The maximum weight average molecular weight (Mw) of polymer that assures soap-free emulsionconversion into hydrosol is about 1.2 × 105-1.3 × 105. The particle transforming process was investigated, and an obviouschange of particle diameter and morphology was observed.

  10. A new coordination mode of (E)-3-(3-hydroxyl-phenyl)-acrylic acid in copper complex: Crystal structure and magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin; Zhou, Pei; Zheng, Chunying [Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, Beijing 100081 (China); Li, Hui, E-mail: lihui@bit.edu [Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, Beijing 100081 (China)

    2015-05-15

    A copper complex ([Cu(py){sub 2}(L){sub 2}]·2CH{sub 3}OH){sub n} (HL=(E)-3-(3-hydroxyl-phenyl)-acrylic acid) (1) with acrylic acid ligand was synthesized and structurally analyzed by IR, elemental analysis, TGA and the single-crystal X-ray diffraction methods. It is the first time to find that phenolic hydroxyl of L coordinates to Cu(II). Complex 1 exhibits 1D chain by a double-bridge of ligands, and the 3D supramolecular framework in complex 1 is constructed by π–π stacking interactions and van der Waals Contacts among the 1D chains. The magnetic properties of complex 1 have been studied. - Graphical abstract: A copper complex based on (E)-3-(3-hydroxyl-phenyl)-acrylic acid in a novel coordinated way was synthesized and a ferromagnetic exchange interactions between neighboring Cu(II) ions has be achieved. - Highlights: • A new copper complex with acrylic acid ligand was synthesized and analyzed. • We find the phenolic hydroxyl of MCA ligand coordinates to metal ion firstly. • A ferromagnetic exchange interactions between Cu(II) ions has been achieved.

  11. Graft copolymerization of acrylic acid to cassava starch-Evaluation of the influences of process parameters by an experimental design method

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, I. W.; Heeres, H. J.; Janssen, L. P. B. M.

    2012-01-01

    The graft copolymerization of cassava starch with acrylic acid was investigated using a free radical initiator system (Fe2+/H2O2 redox system) in water. A comprehensive understanding of the important variables and their interaction has been obtained by applying an experimental design method. In this

  12. Tensile properties of low density polypropylene (LDPE)/palm kernel shell (PKS) biocomposites: The effect of acrylic acid (AA)

    Energy Technology Data Exchange (ETDEWEB)

    Romisuhani, A; Salmah, H [School of Materials Engineering, Universiti Malaysia Perlis, Taman Muhibah, 02600, Jejawi, Perlis (Malaysia); Akmal, H, E-mail: romisuhani@yahoo.com [School of Bioprocess Engineering, Universiti Malaysia Perlis, Taman Muhibah, 02600, Jejawi, Perlis (Malaysia)

    2010-05-15

    The surface of palm kernel was modified by acrylic acid (AA). Low density polyethylene (LDPE) was filled by palm kernel shell at various 0, 10, 20, 30 and 40 php. The effect of AA as a coupling agent on LDPE/PKS biocomposites on tensile properties and morphology was investigated. The results show that the increasing of filler content decreased the tensile strength and break elongation but increased the Young's modulus. The presence of AA indicates higher tensile strength and Young's modulus but lower elongation at break compared to untreated LDPE/PKS biocomposites. The scanning electron microscope study show that the better interfacial interaction between palm kernel shell and low density polyethylene with addition of AA.

  13. Tensile properties of low density polypropylene (LDPE)/palm kernel shell (PKS) biocomposites: The effect of acrylic acid (AA)

    Science.gov (United States)

    Romisuhani, A.; Salmah, H.; Akmal, H.

    2010-05-01

    The surface of palm kernel was modified by acrylic acid (AA). Low density polyethylene (LDPE) was filled by palm kernel shell at various 0, 10, 20, 30 and 40 php. The effect of AA as a coupling agent on LDPE/PKS biocomposites on tensile properties and morphology was investigated. The results show that the increasing of filler content decreased the tensile strength and break elongation but increased the Young's modulus. The presence of AA indicates higher tensile strength and Young's modulus but lower elongation at break compared to untreated LDPE/PKS biocomposites. The scanning electron microscope study show that the better interfacial interaction between palm kernel shell and low density polyethylene with addition of AA.

  14. Removal of reactive dyes from textile wastewater by immobilized chitosan upon grafted Jute fibers with acrylic acid by gamma irradiation

    Science.gov (United States)

    Hassan, Mahmoud S.

    2015-10-01

    Jute fibers were grafted with acrylic acid by gamma irradiation technique. Chitosan was immobilized upon the grafted Jute fibers to be used as an adsorbent for waste reactive dye. The treated Jute fibers were characterized by using of Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effect of Jute treatment on its thermal stability by using thermogravimetric analysis (TGA) and its mechanical properties were investigated. The adsorption isotherm and the different factors affecting the dye adsorption such as pH and contact time were also studied. It was found that the dye adsorption was enhanced in the low pH range and increased with increasing of the contact time, regardless of temperature change.

  15. Poly(acrylic acid)-directed synthesis of colloidally stable single domain magnetite nanoparticles via partial oxidation

    Science.gov (United States)

    Altan, Cem L.; Gurten, Berna; Sadza, Roel; Yenigul, Elcin; Sommerdijk, Nico A. J. M.; Bucak, Seyda

    2016-10-01

    Octahedral, single domain magnetite nanoparticles with average size of ~55 nm were synthesized through oxidative aging of a ferrous hydroxide (Fe(OH)2) precursor at high pH in water. The synthesis was also carried out in the presence of the hydrophilic polymer poly(acrylic acid). Presence of the polymer changed the particle morphology from octahedral to spherical while average size decreased to 40-50 nm. Although these particles have a tendency to precipitate due to their high magnetic moment, dispersions of these particles were obtained in the presence of this particular polymer which made the particles stable in water for several days making them suitable for various biotechnological applications such as cell separation owing to their low toxicity.

  16. PHOTO-INDUCED DOPED POLYANILINE BY THE VINYLIDENE CHLORIDE AND METHYL ACRYLATE COPOLYMER AS PHOTO ACID GENERATOR

    Institute of Scientific and Technical Information of China (English)

    LI Suzhen; WAN Meixiang

    1997-01-01

    The emeraldine base form of polyaniline (PANI) can be doped by a photo-induced doping method. In this method a copolymer of vinylidene chloride and methyl acrylate (VCMAC) was used as photo acid generator which can release proton when it is exposed to ultraviolet light (λ = 254 nm). The structure of PANI-VCMAC system before and after irradiation was characterized by elemental analysis, IR, XPS, and SEM images. Results obtained indicate that the photo-induced doping characteristics, such as doping position and type of charge carriers, are similar to that of PANI doped with HCl. The poor roomtemperature conductivity (~ 10-5S/cm) of PANI-VCMAC system after irradiation may be due to low doping degree (~pH= 3) and the difference in morphology as compared with PANI-HCl film.

  17. Improvement in the behavior of bromelain coupled to pNIPAm polymers containing acrylamide or acrylic acid

    Directory of Open Access Journals (Sweden)

    Rubab Mahmood

    2014-08-01

    Full Text Available Bromelain was coupled to N-isopropyl acrylamide (NIPAmpolymers, synthesized using NIPAm and various concentrations of acrylamide (Ac or acrylic acid (AAc. Incorporation of Ac/AAcinto the polymer increased the LCST (lower critical solutiontemperature in a concentration dependent manner but AAc wasmore effective in this regard; the LCST rose to 40°C when 6 percent AAc was used. Incorporation of Ac/AAc increased the coupling of enzyme to the polymer and the η (effectiveness factor of the coupled enzyme, moderately. Various studies indicate that such incorporation of hydrophilic monomers into the polymer does not impair its capacity to couple enzyme or expression of the activity of bound enzyme but seems to actually improve the stability of the enzyme against heat induced inactivation and alkaline pH.

  18. Preparation of poly(polyethylene glycol methacrylate-co-acrylic acid) hydrogels by radiation and their physical properties

    International Nuclear Information System (INIS)

    The pH-responsive copolymer hydrogels were prepared with the monomers of polyethylene glycol methacrylate and acrylic acid based on γ-ray irradiation technique. The gel content of these copolymer hydrogels varied depending on both the composition of monomers and the radiation dose. Maximum gel percent and degree of crosslinking were obtained at the composition of equal amount of comonomers. These copolymer hydrogels did not show any noticeable change in swelling at lower pH range. However they showed an abrupt increase in swelling at higher pH range due to the ionization of carboxyl groups. This pH-responsive swelling behavior was applied for the insulin carrier via oral delivery. Insulin-loaded copolymer hydrogels released most of their insulin in the simulated intestinal fluid which had a pH of 6.8 but not in the simulated gastric fluid which had a pH of 1.2

  19. Tensile properties of low density polypropylene (LDPE)/palm kernel shell (PKS) biocomposites: The effect of acrylic acid (AA)

    International Nuclear Information System (INIS)

    The surface of palm kernel was modified by acrylic acid (AA). Low density polyethylene (LDPE) was filled by palm kernel shell at various 0, 10, 20, 30 and 40 php. The effect of AA as a coupling agent on LDPE/PKS biocomposites on tensile properties and morphology was investigated. The results show that the increasing of filler content decreased the tensile strength and break elongation but increased the Young's modulus. The presence of AA indicates higher tensile strength and Young's modulus but lower elongation at break compared to untreated LDPE/PKS biocomposites. The scanning electron microscope study show that the better interfacial interaction between palm kernel shell and low density polyethylene with addition of AA.

  20. Radiation synthesis of pH-sensitive hydrogels from {beta}-cyclodextrin-grafted PEG and acrylic acid for drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jie; Rong Liang [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China); Lin Han, E-mail: linhan1205@yahoo.com.cn [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China); Xiao Ruijia; Wu Huifeng [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China)

    2009-07-15

    A water-soluble macromonomer (PEG-{beta}-CD) was synthesised by reaction of {beta}-cyclodextrin with poly(ethylene glycol) diglycidyl ether. Then, a novel hydrogel with pH-sensitivity was prepared by irradiating the mixture of acrylic acid and PEG-{beta}-CD with electron beam. Compared with the normal PAAc hydrogel, this novel hydrogel had a higher swelling ratio at pH 3-8. 5-Fluorouracil (5-FU) was chosen as a model drug, and the kinetics of 5-FU releasing behavior was studied. Compared with the PAAc hydrogel, the results showed the release time of 5-FU from the cyclodextrin containing hydrogel was prolonged. It may be ascribed to the formation of inclusion complexes between the drug molecules and cyclodextrin groups.

  1. Preparation and characterization of mucus-penetrating papain/poly(acrylic acid) nanoparticles for oral drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Christiane; Leithner, Katharina; Hauptstein, Sabine; Hintzen, Fabian [Center for Molecular Biosciences Innsbruck, University of Innsbruck, CCB-Centrum for Chemistry und Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy (Austria); Salvenmoser, Willi [University of Innsbruck, Department for Evolutionary Developmental Biology, Institute of Zoology and Center for Molecular Biosciences (Austria); Bernkop-Schnuerch, Andreas, E-mail: andreas.bernkop@uibk.ac.at [Center for Molecular Biosciences Innsbruck, University of Innsbruck, CCB-Centrum for Chemistry und Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy (Austria)

    2013-01-15

    Particle diffusion through the intestinal mucosal barrier is restricted by the viscoelastic and adhesive properties of the mucus gel layer, preventing their penetration to the underlying absorptive endothelial cells. To overcome this natural barrier, we developed nanoparticles which have a remarkable ability to cleave mucoglycoprotein substructures responsible for the structural and rheological properties of mucus. After rheological screening of various mucolytic proteases, nanoparticles composed of poly(acrylic acid) and papain were prepared and characterized regarding particle size and zeta potential. Analysis of nanoparticles showed mean diameters sub-200 nm (162.8-198.5 nm) and negative zeta potentials advancing the mobility in mucus gel. Using diffusion chamber studies and the rotating diffusion tubes method, we compared the transport rates of papain modified (PAPC) and unaltered poly(acrylic acid) (PAA) particles through freshly excised intestinal porcine mucus. Results of the diffusion assays demonstrated strongly enhanced permeation behavior of PAPC particles owing to local mucus disruption by papain. Improved transport rates, reduction in mucus viscosity and the retarded release of hydrophilic macromolecular compounds make proteolytic enzyme functionalized nanoparticles of substantial interest for improved targeted drug delivery at mucosal surfaces. Although cytotoxicity tests of the nanoparticles could not be performed, safety of papain and PAA was already verified making PAPC particles a promising candidate in the pharmaceutical field of research. The focus of the present study was the development of particles which penetrate the mucus barrier to approach the underlying epithelium. Improvements of particles that penetrate the mucus followed by cell uptake in this direction are ongoing.

  2. Insulin release from islets of Langerhans entrapped in a poly(N-isopropylacrylamide-co-acrylic acid) polymer gel.

    Science.gov (United States)

    Vernon, B; Kim, S W; Bae, Y H

    1999-01-01

    A copolymer of N-isopropylacrylamide (98 mol% in feed) and acrylic acid, poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAAm-co-AAc)), was prepared by free radical polymerization for development of a thermally reversible polymer to entrap islets of Langerhans for a refillable biohybrid artificial pancreas. A 5 wt% solution of the polymer in Hanks' balanced salt solution forms a gel at 37 degrees C that exhibits no syneresis. Diffusion of fluorescein isothiocyanate (FITC) dextrans having molecular weights of 4400 and 70000 were used to evaluate mass transport in the gel at 37 degrees C. Insulin secretion from islets in the polymer gel was also investigated in both static and dynamic systems. The polymer gel exhibited excellent diffusion of FITC dextran 4400 and FITC dextran 70000 with diffusion ratios, D/D0 (ratio of diffusion in the gel to diffusion in water), of 0.20+/-0.04 and 0.35+/-0.17, respectively. Human islets entrapped in the polymer gel showed prolonged insulin secretion in response to basal (5.5 mM) glucose concentration compared to free human islets. Rat islets showed prolonged insulin secretion in response to high (16.5 mM) glucose concentrations compared to free rat islets. Rat islets in the polymer gel maintained insulin secretion in response to the higher glucose concentration for over 26 days. Rat islets entrapped by the polymer also released higher quantities of insulin more rapidly in response to changes in concentrations of glucose and other stimulants than rat islets entrapped in an alginate control. These results suggest that this material would provide adequate diffusion for rapid insulin release in an application as a synthetic extracellular matrix for a biohybrid artificial pancreas.

  3. Preparation and characterization of mucus-penetrating papain/poly(acrylic acid) nanoparticles for oral drug delivery applications

    International Nuclear Information System (INIS)

    Particle diffusion through the intestinal mucosal barrier is restricted by the viscoelastic and adhesive properties of the mucus gel layer, preventing their penetration to the underlying absorptive endothelial cells. To overcome this natural barrier, we developed nanoparticles which have a remarkable ability to cleave mucoglycoprotein substructures responsible for the structural and rheological properties of mucus. After rheological screening of various mucolytic proteases, nanoparticles composed of poly(acrylic acid) and papain were prepared and characterized regarding particle size and zeta potential. Analysis of nanoparticles showed mean diameters sub-200 nm (162.8–198.5 nm) and negative zeta potentials advancing the mobility in mucus gel. Using diffusion chamber studies and the rotating diffusion tubes method, we compared the transport rates of papain modified (PAPC) and unaltered poly(acrylic acid) (PAA) particles through freshly excised intestinal porcine mucus. Results of the diffusion assays demonstrated strongly enhanced permeation behavior of PAPC particles owing to local mucus disruption by papain. Improved transport rates, reduction in mucus viscosity and the retarded release of hydrophilic macromolecular compounds make proteolytic enzyme functionalized nanoparticles of substantial interest for improved targeted drug delivery at mucosal surfaces. Although cytotoxicity tests of the nanoparticles could not be performed, safety of papain and PAA was already verified making PAPC particles a promising candidate in the pharmaceutical field of research. The focus of the present study was the development of particles which penetrate the mucus barrier to approach the underlying epithelium. Improvements of particles that penetrate the mucus followed by cell uptake in this direction are ongoing.

  4. Preparation of poly(acrylamide-co-acrylic acid)-grafted gum and its flocculation and biodegradation studies.

    Science.gov (United States)

    Mittal, H; Mishra, Shivani B; Mishra, A K; Kaith, B S; Jindal, R; Kalia, S

    2013-10-15

    Biodegradation studies of Gum ghatti (Gg) and acrylamide-co-acrylic acid based flocculants [Gg-cl-poly(AAm-co-AA)] have been reported using the soil composting method. Gg-cl-poly(AAm-co-AA) was found to degrade 89.76% within 60 days. The progress of biodegradation at each stage was monitored through FT-IR and SEM. Polymer was synthesized under pressure using potassium persulphate-ascorbic acid as a redox initiator and N,N'-methylene-bis-acrylamide as a crosslinker. Synthesized polymer was found to show pH, temperature and ionic strength of the cations dependent swelling behavior. Gg-cl-poly(AAm-co-AA) was utilized for the selective absorption of saline from different petroleum fraction-saline emulsions. The flocculation efficiency of the polymer was studied as a function of polymer dose, temperature and pH of the solution. Gg-cl-poly(AAm-co-AA) showed maximum flocculation efficiency with 20 mol L(-1) polymer dose in acidic medium at 50 °C. PMID:23987360

  5. In vitro release studies of vitamin B12 from poly N-vinyl pyrrolidone /starch hydrogels grafted with acrylic acid synthesized by gamma radiation

    International Nuclear Information System (INIS)

    Co-polymeric hydrogels containing N-vinyl pyrrolidone and starch grafted with acrylic acid were synthesized by gamma radiation. Their gel contents, grafting process and swelling were evaluated. The gels were also characterized by thermal gravimetric analysis. The gel content found to be increase with increasing the irradiation dose up to 50 kGy then decrease. The grafting percent increase by increasing the percentage of acrylic acid in the grafted hydrogels. The thermal stability and the rate of the thermal decomposition showed to be changed according to the different composition of the hydrogels. It also showed a decrease in the maximum rate of the thermal decomposition by the increasing of the irradiation dose from 20 to 30 kGy and increases by increasing the irradiation dose from 30 to 70 kGy. The hydrogels loaded with vitamin B12 as drug model, demonstrated a decrease release in acidic medium than the neutral one

  6. Poly(acrylic acid)/polyethylene glycol hygrogel prepared by using gamma-ray irradiation for mucosa adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young-Chang; Park, Jong-Seok; Shin, Jung-Woong; Lim, Youn-Mook; Jeong, Sung-In; Shin, Young-Min; Gwon, Hui-Jeong [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Khil, Myung-Seob [Chonbuk National University, Jeonju (Korea, Republic of); Lee, Deok-Won [Maxillofacial Surgery Dental Hospital, Seoul (Korea, Republic of); Ahn, Sung-Jun [JADAM Co., LTD., Seogwipo (Korea, Republic of)

    2015-01-15

    A buccal delivery system provides a much milder environment for drug delivery compared to an oral delivery which presents a hostile environment for drugs, especially proteins and polypeptides, owing to acid hydrolysis. Local delivery in an oral cavity has particular applications in the treatment of toothaches, periodontal disease, and bacterial infections. Poly(acrylic acid) (PAA)-based hydrogels prepared using a chemical initiator have been attempted for a mucoadhesive system owing to their flexibility and excellent bioadhesion. In this experiment, PAA and polyethylene glycol (PEG) were selected to prepare using a radiation process a bioadhesive hydrogel for adhesion to mucosal surfaces. PAA and PEG were dissolved in purified water to prepare a homogeneous PAA/PEG solution, and the solution was then irradiated using an electron beam at dose up to 70 kGy to make the hydrogels. Their physical properties, such as gel percent, swelling percent, and adhesive strength to mucosal surfaces, were investigated. In this experiment, various amounts of PEG were incorporated into the PAA to enhance the mucoadhesive property of the hydrogels. The effect of the molecular weight of PEG on the mucoadhesion was also examined.

  7. Diffusion coefficient, porosity measurement, dynamic and equilibrium swelling studies of Acrylic acid/Polyvinyl alcohol (AA/PVA hydrogels

    Directory of Open Access Journals (Sweden)

    Nazar Mohammad Ranjha

    2015-06-01

    Full Text Available Objective of the present work was to synthesize hydrogels of acrylic acid/polyvinyl alcohol (AA/PVA by free radical polymerization by using glutaradehyde (GA as crosslinkers. The hydrogels were evaluated for swelling, diffusion coefficient and network parameters like the average molecular weight between crosslink’s, polymer volume fraction in swollen state, number of repeating units between crosslinks and crosslinking density by using Flory-Huggins theory. It was found that the degree of swelling of AA/PVA hydrogels increases greatly within the pH range 5-7. The gel fraction and porosity increased by increasing the concentration of AA or PVA. Increase in degree of crosslinking, decreased the porosity and inverse was observed in gel fraction. Selected samples were loaded with metoprolol tartrate. Drug release was studied in USP hydrochloric acid solution of pH 1.2 and phosphate buffer solutions of pH 5.5 and 7.5. Various kinetics models like zero order, first order, Higuchi and Peppas model were used for in vitro kinetic studies. The results showed that the drug release followed concentration dependent effect (First order kinetics with non-Fickian diffusion. FTIR and SEM used to study the structure, crystallinity, compatibility, thermal stability and morphology of prepared and drug loaded hydrogels respectively.

  8. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat [Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Amin, Mohd. Cairul Iqbal Mohd [Faculty of Pharmacy, University Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur (Malaysia)

    2014-09-03

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  9. Optimal Design for Reactivity Ratio Estimation: A Comparison of Techniques for AMPS/Acrylamide and AMPS/Acrylic Acid Copolymerizations

    Directory of Open Access Journals (Sweden)

    Alison J. Scott

    2015-11-01

    Full Text Available Water-soluble polymers of acrylamide (AAm and acrylic acid (AAc have significant potential in enhanced oil recovery, as well as in other specialty applications. To improve the shear strength of the polymer, a third comonomer, 2-acrylamido-2-methylpropane sulfonic acid (AMPS, can be added to the pre-polymerization mixture. Copolymerization kinetics of AAm/AAc are well studied, but little is known about the other comonomer pairs (AMPS/AAm and AMPS/AAc. Hence, reactivity ratios for AMPS/AAm and AMPS/AAc copolymerization must be established first. A key aspect in the estimation of reliable reactivity ratios is design of experiments, which minimizes the number of experiments and provides increased information content (resulting in more precise parameter estimates. However, design of experiments is hardly ever used during copolymerization parameter estimation schemes. In the current work, copolymerization experiments for both AMPS/AAm and AMPS/AAc are designed using two optimal techniques (Tidwell-Mortimer and the error-in-variables-model (EVM. From these optimally designed experiments, accurate reactivity ratio estimates are determined for AMPS/AAm (rAMPS = 0.18, rAAm = 0.85 and AMPS/AAc (rAMPS = 0.19, rAAc = 0.86.

  10. Mechanism of poly(acrylic acid) acceleration of antithrombin inhibition of thrombin: implications for the design of novel heparin mimics.

    Science.gov (United States)

    Monien, Bernhard H; Cheang, Kai I; Desai, Umesh R

    2005-08-11

    The bridging mechanism of antithrombin inhibition of thrombin is a dominant mechanism contributing a massive approximately 2500-fold acceleration in the reaction rate and is also a key reason for the clinical usage of heparin. Our recent study of the antithrombin-activating properties of a carboxylic acid-based polymer, poly(acrylic acid) (PAA), demonstrated a surprisingly high acceleration in thrombin inhibition (Monien, B. H.; Desai, U. R. J. Med. Chem. 2005, 48, 1269). To better understand this interesting phenomenon, we have studied the mechanism of PAA-dependent acceleration in antithrombin inhibition of thrombin. Competitive binding studies with low-affinity heparin and a heparin tetrasaccharide suggest that PAA binds antithrombin in both the pentasaccharide- and the extended heparin-binding sites, and these results are corroborated by molecular modeling. The salt-dependence of the K(D) of the PAA-antithrombin interaction shows the formation of five ionic interactions. In contrast, the contribution of nonionic forces is miniscule, resulting in an interaction that is significantly weaker than that observed for heparins. A bell-shaped profile of the observed rate constant for antithrombin inhibition of thrombin as a function of PAA concentration was observed, suggesting that inhibition proceeds through the "bridging" mechanism. The knowledge gained in this mechanistic study highlights important rules for the rational design of orally available heparin mimics. PMID:16078853

  11. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    Science.gov (United States)

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-01

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  12. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    International Nuclear Information System (INIS)

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier

  13. Modification of Oxidized Paraffin Wax Grafted by Acrylic Acid%氧化蜡接枝丙烯酸的改性研究

    Institute of Scientific and Technical Information of China (English)

    陈鹏; 纪灵娴; 王德; 丛玉凤; 黄玮

    2013-01-01

    Melted oxidized paraffin wax grafted by acrylic acid was studied in this paper ,it was discussed respectively about factors influencing grafted rate of melted oxidized paraffin wax , like reaction temperature , the dosage of ammonium persulphate ,the dosage of acrylic acid and reaction time etc .It was ascertained that the proper conditions of orthogonal technology of melted oxidized paraffin wax grafted by acrylic acid ,reaction temperature was 85 ℃ ,the dosage of ammonium persulphate 3 .5% ~ 4 .5% , the dosage of acrylic acid 40% , reaction time 3 h .Finally , according to optimum proposal summarized by orthogonal experiment ,modified oxidized paraffin wax was prepared with great characters of acid value ,grafted rate ,storage and centrifuge stability etc .%对丙烯酸接枝熔融氧化蜡进行了研究,分别探讨了反应温度、过硫酸铵质量分数、丙烯酸质量分数、反应时间等因素对熔融氧化蜡的接枝率的影响,确定了合适的丙烯酸接枝熔融氧化蜡的正交工艺条件为:反应温度为85℃,过硫酸铵质量分数为3.5%~4.5%,丙烯酸质量分数为40%,反应时间为3h,最终按照正交实验总结出的优化方案制备出了接枝率、酸值、贮存与离心稳定性等性质优异的改性氧化蜡。

  14. Storage Stability Improvement of Copolymer Grafted Polypropylene-AcrylicAcid (PP-AA), by means of Various After Treatment Processes

    International Nuclear Information System (INIS)

    Polypropylene yams that have been subjected to irradiation induced graftco-polymerization with acrylic acid, have gained its moisture regain and dyeability, that fulfilled the requirement as textile material for garment.However, the copolymer grafted PP-AA has suffered from degradation in thestorage, which was indicated in the previous study that the strengthretention has dropped tremendously by photo-oxidation or photo-degradation.After treatments of PP-AA yams with chemical compound that was able toprevent further photo-oxidation, will be expected to improve the stability ofPP-AA in storage. In this research activity, the polypropylene (PP) yams weresubjected to irradiation induced graft co-polymerization by means ofγ-Ray Co-60 as irradiation source with acrylic acid (AA) as monomer.Various after treatments were subjected to the grafted PP-AA yams such asalkalisation process; dyeing (anionic dyes, cationic dyes and nonionic dyes);as well as processing with optical brightening agent and UV stabilizer,separately. The PP-AA yams (before and after treatment) were subjected tostorage from 1 month up to 42 months, and then being tested for theirmoisture regain, strength retention and elongation at breaks. The samplesbeing stored for 12 months were subjected to radical analysis. It isconcluded from the experiment that after treatment of grafted PP-AA by meansof those various processes were able to improve the stability of copolymergrafted PP-AA in storage. The presence of peroxide radical in the ESR(electron spin resonance) spectrum on PP-AA yams before treatment and theones after treated with alkaline and being stored for 12 months haveindicated the presence of photo oxidation or photo degradation, while thepresence of poly enyl radical in the ESR spectrum of after treated PP-AA withdyes having azo and azine compound as chromophore, as well as with UVstabilizer with carbonyl as chromophore and being stored for 12 months haveproved that its presence have protected such

  15. Electroactive behavior of poly(acrylic acid) grafted poly(vinyl alcohol) samples, their synthesis using a Ce(IV) glucose redox system and their characterization

    Science.gov (United States)

    Kurkuri, Mahaveer D.; Lee, Jae-Rock; Han, Jae Hung; Lee, In

    2006-04-01

    Grafted copolymers of poly(acrylic acid) (PAA) and poly(vinyl alcohol) (PVA) were prepared using a Ce(IV) glucose redox initiator by free radical polymerization. Three grafted copolymers having 20%, 50% and 80% grafting were selected for this study. Thus-modified polymer was characterized by means of Fourier transform infrared spectra, 1H NMR, gel permeation chromatography, thermogravimetric analysis and universal testing machine approaches. The membranes were prepared by a solution casting method, where the cross-linking process was performed through the in situ addition of glutaraldehyde and hydrochloric acid as the cross-linking agent and catalyst respectively. The following four membranes were prepared: (i) pure PVA; (ii) 20% grafted PVA; (iii) 50% grafted PVA; (iv) 80% grafted PVA. The membranes obtained were employed in the electroactive behavior study under a DC electric stimulus in different concentrations of electrolyte. The equilibrium bending angles (EBA) of these polymers were studied with respect to time, poly(acrylic acid) content, electric voltage applied across the polymer and ionic strength of the electrolyte used. Experimental results show stable reversibility of the bending behavior of these polymers under an applied DC electric field. The EBA increased with increase in the applied electric voltage and poly(acrylic acid) content within the polymer.

  16. Synthesis of Graft Copolymer of Sodium Humate-Acrylic Acid%腐植酸钠-丙烯酸接枝共聚物的合成研究

    Institute of Scientific and Technical Information of China (English)

    张荣明; 生金峰; 李鹏; 程焱召

    2011-01-01

    Grafting copolymerization of sodium humate with acrylic acid initiated by potassium persulfate was studied by aqueous solution polymerization method. The influential factors, such as reaction temperature, reaction time, initiator rate, the neutralization degree of acrylic acid and the reactant mass ratio were explored. The results showed that the optimum condition was 90% neutralization degree of acrylic acid, 50:1 (g/g) of acrylic acid to sodium humate, 4.0% initiator in reactant (compared with AA), and 60℃ for 8h. The structure of product was characterizedby IR.%采用水溶液聚合方法,以过硫酸钾为引发剂,腐植酸、丙烯酸为原料接枝共聚。考察了丙烯酸中和度、引发剂用量、物料比、反应温度和反应时间等因素对合成腐植酸钠-丙烯酸接枝共聚物的影响。结果表明,最佳聚合工艺条件为:丙烯酸中和度90%,反应温度60℃,反应时间8h,加入引发剂浓度为4.0%(AA单体为参照),丙烯酸与腐植酸钠物料比为50:1(g/g),通过红外光谱对聚合物的结构进行了表征。

  17. Synthesis of silica coated zinc oxide–poly(ethylene-co-acrylic acid) matrix and its UV shielding evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ramasamy, Mohankandhasamy [Division of Bionanotechnology, Gachon University, Seongnam 461-701 (Korea, Republic of); Kim, Yu Jun; Gao, Haiyan [Department of Polymer Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Yi, Dong Kee, E-mail: vitalis@mju.ac.kr [Department of Chemistry, Myongji University, Yongin 449-728 (Korea, Republic of); An, Jeong Ho, E-mail: jhahn1us@skku.edu [Department of Polymer Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-03-01

    Graphical abstract: - Highlights: • Well layer thickness controlled silica shell was made on ZnO nanoparticles. • PEAA, an interfacial agent is used to make nanocomposite–polymer matrix by twin-screw extruder. • Si-ZnO/PEAA matrix is highly stable and UV protective as compared to ZnO/PEAA matrix. • Nanoparticle embedded polymer matrix is suggested to make UV shielding fabrics with Nylon4. - Abstract: Silica coated zinc oxide nanoparticles (Si-ZnO NPs) (7 nm thick) were synthesized successfully and melt blended with poly(ethylene-co-acrylic acid) (PEAA resin) to improving ultraviolet (UV) shielding of zinc oxide nanoparticles (ZnO NPs). The photostability of both the ZnO NPs and Si-ZnO NPs were analyzed by the difference in photoluminescence (PL) and by methylene blue (MB) degradation. Photo-degradation studies confirmed that Si-ZnO NPs are highly photostable compared to ZnO NPs. The melt blended matrices were characterized by field emission scanning electron microscopy interfaced with energy dispersive X-ray spectroscopy (FE-SEM-EDX). The UV shielding property was analyzed from the transmittance spectra of UV–visible (UV–vis) spectroscopy. The results confirmed fine dispersion of thick Si-ZnO NPs in the entire resin matrix. Moreover, the Si-ZnO/PEAA showed about 97% UV shielding properties than the ZnO/PEAA.

  18. Capture of Tumor Cells on Anti-EpCAM-Functionalized Poly(acrylic acid)-Coated Surfaces.

    Science.gov (United States)

    Andree, Kiki C; Barradas, Ana M C; Nguyen, Ai T; Mentink, Anouk; Stojanovic, Ivan; Baggerman, Jacob; van Dalum, Joost; van Rijn, Cees J M; Terstappen, Leon W M M

    2016-06-15

    The presence of tumor cells in blood is predictive of short survival in several cancers and their isolation and characterization can guide toward the use of more effective treatments. These circulating tumor cells (CTC) are, however, extremely rare and require a technology that is sufficiently sensitive and specific to identify CTC against a background of billions of blood cells. Immuno-capture of cells expressing the epithelial cell adhesion molecule (EpCAM) are frequently used to enrich CTC from blood. The choice of bio conjugation strategy and antibody clone is crucial for adequate cell capture but is poorly understood. In this study, we determined the binding affinity constants and epitope binding of the EpCAM antibodies VU1D-9, HO-3, EpAb3-5, and MJ-37 by surface plasmon resonance imaging (SPRi). Glass surfaces were coated using a poly(acrylic acid) based coating and functionalized with anti-EpCAM antibodies. Binding of cells from the breast carcinoma cell line (SKBR-3) to the functionalized surfaces were compared. Although EpAb3-5 displayed the highest binding affinity HO-3 captured the highest amount of cells. Hence we report differences in the performance of the different antibodies and more importantly that the choice of antibody to capture CTC should be based on multiple assays. PMID:27187784

  19. STUDY OF COMPOSITE MEMBRANE OF CELLULOSE ACETATE OR POLYVINYL ALCOHOL BLENDED WITH METHYLMETHACRYLATE-ACRYLIC ACID COPOLYMER FOR PERVAPORATION SEPARATION

    Institute of Scientific and Technical Information of China (English)

    Huan-lin Chen; Jun Tan; Mo-e Liu; Chang-luo Zhu

    1999-01-01

    In this paper, methylmethacrylate-acrylic acid MMA-AA hydrophilic and hydrophobic copolymers were prepared by copolymerization for preparing membrane materials. The composite membrane of cellulose acetate (CA) blended with MMA-AA hydrophobic copolymer was used for the separation of methanol from pentane-methanol mixture. When the methanol concentration was only 1 wt%, the permeate flux still maintained at 350 g/m2h and separation factor was as big as 800. The composite membrane of PVA (polyvinyl alcohol) blended with MMA-AA hydrophilic copolymer was used for the separation of ethanolwater mixture. The permeate flux was increased to 975 g/m2h at 74℃ and the separation factor reached 3000at 25℃. The PVA/MMA-AA blended membrane surface modified by ammonia plasma was also investigated for separating ethanol-water mixture. Both permeate flux and separation factor of the membrane was improved. However, there was no obvious difference of plasma treatment time in the interval of 20~40 min.

  20. A drug-loaded gel based on polyelectrolyte complexes of poly (acrylic acid) with poly (vinylpyrrolidone) and chitosan

    International Nuclear Information System (INIS)

    A drug-loaded gel (CSPP) based on ionic crosslinked chitosan (CS) and polyelectrolyte complexes of poly (acrylic acid) (PAA) with poly (vinylpyrrolidone) (PVP) was prepared by dropping CS solution containing suitable amount of PVP into PAA and trisodium citrate co-existing gelling solution. The surface and cross-section morphology of the gel was observed using scanning electron microscopy, and the observation showed that the CSPP gel had more compact structure than CS gel. In vitro release profiles of model drug from the CSPP gel, which was prepared under different conditions, were investigated in simulative gastric fluid (pH 1.8) using an UV/vis spectrophotometer. The results showed that the rapid release of the model was restrained due to the complex of PVP and PAA, and the CSPP gel could serve as a suitable candidate in drug delivery system such as the site-specific controlled release of the drug in stomach. In addition, the release mechanism of drug was analyzed by fitting the amount of drug released into Peppa's potential equation.

  1. Acrylic acid-allylpolyethoxy carboxylate copolymer dispersant for calcium carbonate and iron(III) hydroxide scales in cooling water systems

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guangqing; Huang, Jingyi; Zhou, Yuming; Yao, Qingzhao; Ling, Lei; Zhang, Peixin; Fu, Change [Southeast Univ., Nanjing (China). School of Chemistry and Chemical Engineering; Wu, Wendao; Sun, Wei; Hu, Zhengjun [Jianghai Chemical Co., Ltd., Changzhou (China)

    2012-05-15

    A novel environmentally friendly type of calcium carbonate and iron(III) scale inhibitor (ALn) was synthesized. The anti-scale property of the Acrylic acid-allylpolyethoxy carboxylate copolymer (AA-APELn or ALn) towards CaCO{sub 3} and iron(III) in the artificial cooling water was studied through static scale inhibition tests. The observation shows that both calcium carbonate and iron(III) inhibition increase with increasing the degree of polymerization of ALn from 5 to 15, and the dosage of ALn plays an important role on calcium carbonate and iron(III)-inhibition. The effect on formation of CaCO{sub 3} was investigated with a combination of scanning electronic microscopy (SEM), Transmission electron microscopy (TEM), X-ray powder diffraction (XRD) analysis and Fourier transform infrared spectrometer, respectively. The results showed that the ALn copolymer not only influences calcium carbonate crystal morphology and crystal size but also the crystallinity. The crystallization of CaCO{sub 3} in the absence of inhibitor was rhombohedral calcite crystal, whereas a mixture of calcite with vaterite crystals was found in the presence of the ALn copolymer. Inhibition mechanism is proposed that the interactions between calcium or iron ions and polyethylene glycol (PEG) are the fundamental impetus to restrain the formation of the scale in cooling water systems. (orig.)

  2. Starch-g-Poly-(N, N-dimethyl acrylamide-co-acrylic acid): an efficient Cr (VI) ion binder.

    Science.gov (United States)

    Kolya, Haradhan; Roy, Anirban; Tripathy, Tridib

    2015-01-01

    Synthesis of Starch-g-(Poly N, N-dimethylacrylamide-co-acrylic acid) was carried out by solution polymerization technique using potassium perdisulfate (K(2)S(2)O(8)) as the initiator. The graft copolymer was characterized by measuring molecular weight, using size exclusion chromatography (SEC), FTIR spectroscopy and X-ray diffraction (XRD) studies. The synthetic graft copolymer was used for removal of hexavalent chromium ion [Cr (VI)] from its aqueous solution. Various operating variables affecting the metal sorption such as, the amount of adsorbent, solution pH, contact time, temperature and the Cr (VI) solution concentration were extensively investigated. FTIR and UV-VIS spectroscopy, cyclic voltammetry (CV) were employed to study the metal complexation. The adsorption data could be well described by the pseudo-second-order and Langmuir isotherm model which indicate a chemisorption process. Calculation of the various thermodynamic parameters for the adsorption was also done. The negative value of free energy change (ΔG°) indicates the spontaneous nature of the adsorption. PMID:25224290

  3. Synthesis and colon-specific drug delivery of a poly(acrylic acid-co-acrylamide)/MBA nanosized hydrogel.

    Science.gov (United States)

    Ray, Debajyoti; Mohapatra, Dillip K; Mohapatra, Ranjit K; Mohanta, Guru P; Sahoo, Prafulla K

    2008-01-01

    Intravenous administration of 5-fluorouracil (5-FU) for colon cancer therapy produces severe systemic side-effects due to its cytotoxic effect on normal cells. The main objective of the present study was to develop novel oral site-specific delivery of 5-FU to the colon with less drug being released in the stomach or small intestine using biodegradable hydrogel, hydrogel nanoparticles and comparing the targeting efficiency of 5-FU to colon from both. Poly(acrylic acid-co-acrylamide) (P(AA-co-Am)) normal hydrogel and hydrogel nanoparticles (HN) were synthesized by free radical polymerization using N,N-methylene-bis-acrylamide (MBA) as cross-linker, potassium persulfate as reaction initiator and 5-FU was loaded. HN were found to be degradable in physiological medium and showed comparatively higher swelling in rat caecal medium (RCM). 5-FU entrapment was increased by increasing Am (wt%) monomer feed. In vitro release of 5-FU from normal hydrogel and HN in pH progressive medium, it was found that a AA/Am ratio of 25:75 showed higher release in RCM. The Higuchi model yielded good adjustment of in vitro release kinetics. A higher amount of 5-FU reached the colon in HN (61 +/- 2.1%) than normal hydrogel (40 +/- 3.6%) by organ biodistribution studies in albino rats. PMID:18973725

  4. [Preparation of Pb2+ imprinted acrylic acid-co-styrene and analysis of its adsorption properties by FAAS].

    Science.gov (United States)

    Shawket, Abliz; Abdiryim, Supahun; Wang, Ji-De; Ismayil, Nurulla

    2011-06-01

    With lead ion template, acrylic acid as functional monomer, potassium persulfate as initiator, strytrene as framework monomer, lead ion imprinted polymers (Pb(II)-IIPs) were prepared using free emulsion polymerization method. The structure and morphology of the polymers were analyzed by UV-spectra, FTIR and scanning electron microscopy. The adsorption/ desorption and selectivity for Pb2+ were investigated by flame atomic absorption spectrometry (FAAS) as the detection means. The results show that compared with non-imprinted polymers(NIPs), the Pb(II)-IIPs had higher specific adsorption properties and selective recognition ability for Pb(II). The relative selectivity coefficient of Pb(II)-IIPs for Pb(II) was 6.25, 6.18, 6.25 and 6.38 in the presence of Cd(II), Cu(II), Mn(II) and Zn(II) interferences, respectively. The absorption rate was the best at the pH of adsorbent solution of 6, Adsorption rate reached 96% during the 2.5 h static adsorption time. Using 3.0 mol x L(-1) HCI as the best desorption solvent to desorb the adsorbents, the desorbtion rate reached 98%. Under the best adsorption conditions, the adsorption capacity of Pb(II)-IIPs for Pb(II) was found to be 40. mg x g(-1). PMID:21847962

  5. Characterization and Antimicrobial Property of Poly(Acrylic Acid) Nanogel Containing Silver Particle Prepared by Electron Beam

    Science.gov (United States)

    Choi, Jong-Bae; Park, Jong-Seok; Khil, Myung-Seob; Gwon, Hui-Jeong; Lim, Youn-Mook; Jeong, Sung-In; Shin, Young-Min; Nho, Young-Chang

    2013-01-01

    In this study, we developed a one step process to synthesize nanogel containing silver nanoparticles involving electron beam irradiation. Water-soluble silver nitrate powder is dissolved in the distilled water and then poly(acrylic acid) (PAAc) and hexane are put into this silver nitrate solution. These samples are irradiated by an electron beam to make the PAAc nanogels containing silver nanoparticles (Ag/PAAc nanogels). The nanoparticles were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In addition, the particle size and zeta-potential were confirmed by a particle size analyzer (PSA). The antibacterial properties of the nanogels were evaluated by paper diffusion test. The Ag/PAAc nanogels had an antibacterial effect against Escherichia coli and Staphylococcus aureus. The nanogels also demonstrated a good healing effect against diabetic ulcer. The size of the Ag/PAAc nanogels decreased with increasing irradiation doses, and the absolute value of the zeta potential increased with increasing irradiation doses. Also, the Ag/PAAc nanogels exhibited good antibacterial activity against both Gram-negative and Gram-positive bacteria. In in vivo wound healing, the Ag/PAAc nanogels have a good healing effect. PMID:23708101

  6. Radiation crosslinked poly (vinyl alcohol/acrylic acid copolymer for removal of heavy metal ions from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Yahya H.F. Al-qudah

    2014-04-01

    Full Text Available Poly(vinyl alcohol and acrylic acid (AAc were copolymerized in different compositions using gamma irradiation. Swelling characteristics of the obtained polymeric hydrogels (PVA/AAc were evaluated and showed reasonable sensitivity to both pH and temperature. The diffusion of water within the hydrogel was found to be of Fickian character, the water molecules may simply diffuse through the polymer network by diffusion processes. The adsorption of Zn2+, Co2+ and Mn2+ ions onto (PVA/AAc has been investigated. The parameters studied including; the effects of pH, contact time and the initial metal ion concentrations by batch method. It was found that the adsorption of Zn2+, Co2+ and Mn2+ ions by PVA/AAc hydrogel is pH-dependent and the maximum sorption of Zn2+, Co2+ and Mn2+ was found to be 388, 245 and 152 mg/g, respectively, at pH 5. The adsorption studies are fitted in various adsorption models such as Langmuir and Freundlich. The kinetic data was tested using pseudo-first-order, pseudo-second-order kinetic models and an intraparticle diffusion model. The correlation results suggested that the pseudo-second-order model was the best choice among all the kinetic models to describe the adsorption behavior.

  7. Dually cross-linked single network poly(acrylic acid) hydrogels with superior mechanical properties and water absorbency.

    Science.gov (United States)

    Zhong, Ming; Liu, Yi-Tao; Liu, Xiao-Ying; Shi, Fu-Kuan; Zhang, Li-Qin; Zhu, Mei-Fang; Xie, Xu-Ming

    2016-06-28

    Poly(acrylic acid) (PAA) hydrogels with superior mechanical properties, based on a single network structure with dual cross-linking, are prepared by one-pot free radical polymerization. The network structure of the PAA hydrogels is composed of dual cross-linking: a dynamic and reversible ionic cross-linking among the PAA chains enabled by Fe(3+) ions, and a sparse covalent cross-linking enabled by a covalent cross-linker (Bis). Under deformation, the covalently cross-linked PAA chains remain intact to maintain their original configuration, while the Fe(3+)-enabled ionic cross-linking among the PAA chains is broken to dissipate energy and then recombined. It is found that the mechanical properties of the PAA hydrogels are significantly influenced by the contents of covalent cross-linkers, Fe(3+) ions and water, which can be adjusted within a substantial range and thus broaden the applications of the hydrogels. Meanwhile, the PAA hydrogels have excellent recoverability based on the dynamic and reversible ionic cross-linking enabled by Fe(3+) ions. Moreover, the swelling capacity of the PAA hydrogels is as high as 1800 times in deionized water due to the synergistic effects of ionic and covalent cross-linkings. The combination of balanced mechanical properties, efficient recoverability, high swelling capacity and facile preparation provides a new method to obtain high-performance hydrogels. PMID:27230478

  8. Investigation of Regenerated Cellulose/Poly(acrylic acid Composite Films for Potential Wound Healing Applications: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Manjula Bajpai

    2014-01-01

    Full Text Available Regenerated cellulose/poly(acrylic acid composite films have been synthesized for wound dressing applications. The water absorbency of these films was studied as a function of amount of cross-linker N,N′-methylenebisacrylamide and cellulose contents in the feed mixture. The samples, having different compositions, showed tensile strength and percent elongation in the range of 9.98×105 to 13.40×105 N/m2 and 110 to 265, respectively. The water vapor transmission rate (WVTR for various films was found to be in the range of 2.03 to 7.18 mg/cm2/h. These films were loaded with antibacterial drug miconazole nitrate and their release was studied in the physiological pH at 37°C. The release data was found to fit well the diffusion controlled Higuchi model. Finally the films demonstrated fair antibacterial and antifungal action, thus establishing their strong candidature as wound dressing materials.

  9. Preparation of mesoporous poly (acrylic acid)/SiO2 composite nanofiber membranes having adsorption capacity for indigo carmine dye

    Science.gov (United States)

    Xu, Ran; Jia, Min; Li, Fengting; Wang, Hongtao; Zhang, Bingru; Qiao, Junlian

    2012-03-01

    Mesoporous poly (acrylic acid)/SiO2 (PAA/SiO2) composite nanofiber membranes functionalized with mercapto groups were fabricated by a sol-gel electrospinning method, and their adsorption capacity for indigo carmine was investigated. The membranes were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, x-ray powder diffraction (XRD), and nitrogen adsorption-desorption measurement. SEM and TEM observation results showed that the PAA/SiO2 fibers had diameters between 400-800 nm and mesopores with an average pore size of 3.88 nm. The specific surface area of the mesoporous nanofiber membranes was 514.89 m2/g. The characteristic peaks for mercapto group vibration in FTIR and Raman spectra demonstrated that the mercapto groups have been incorporated into the silica skeleton. The adsorption isotherm data of indigo carmine on the membranes fit well with Redlich-Peterson model, and the maximum adsorption capacity calculated was 523.11 mg/g. It was found that the removal rate of indigo carmine by the membranes reached a maximum of 98% in 90 min and the adsorption kinetics followed a pseudo-second-order model. The high adsorption capacity of PAA/SiO2 nanofiber membrane makes it a promising adsorbent for indigo carmine removal from the wastewater.

  10. [The application of Harpagophytum procumbens extract in anti-inflammatory preparations applied on skin produced on acrylic acid polymers base].

    Science.gov (United States)

    Piechota-Urbańska, Magdalena; Kołodziejska, Justyna; Berner-Strzelczyk, Aneta

    2009-01-01

    An attempt was made to use dry standardized extract from Harpagophytum procumbens of confirmed anti-inflammatory activity in formulations applied on skin. To obtain synergy in the area of analgesic and anti-inflammatory activity formulations were produced containing plant extract and nonsteroidal anti-inflammatory drug (ketoprofen). All the preparations were prepared on the base of acrylic acid polymers (Carbopol Ultrez 10, Carbopol 980). The formulations were subjected to complementary physicochemical investigations. Viscosity parameters (structural viscosity, yield stress, thixotrophy) were determined with cone-plate digital rheometer. Potentiometric method was used to measure pH of the produced hydrogels. The test for ketoprofen pharmaceutical availability through a semipermeable membrane to acceptor fluid was performed in vitro. The rate of the process of release was tested by determining the quantity of the therapeutic agent diffusing into acceptor fluid at defined time intervals by spectrophotometric method. The effect of Harpagophytum procumbens extract components on ketoprofen diffusion was estimated. Viscosity tests revealed that all the formulations are viscoelastic systems having yield stress. All model formulations were tested 24h after production and after 6-month storage. All the formulations demonstrate rheological stability and high pharmaceutical availability of ketoprofen. The suggested formulations can be an alternative for market preparations applied on skin of anti-inflammatory and analgesic activity. PMID:19873929

  11. Structure formation of soil dispersions in the presence of polyelectrolytes on the basis of allyl alcohol and acryl acid derivatives

    Directory of Open Access Journals (Sweden)

    Amankait Asanov

    2015-09-01

    Full Text Available Some changes of structural composition and surface properties of soil dispersions in the presence of polyelectrolytes, based on allyl alcohol and acryl acid derivatives, have been studied. The results show, that the changes in the structure of soil dispersions composition are connected with the added concentration and pH value, that depend on mole ratio and nature of functional groups, as well as on the nature of counterions and concomitant electrolytes, changing with the conditions of polymer analogous conversion and neutralization reaction. Experimental data show, that the change in the conformational state and the length of the macromolecule has a significant impact on the structure-forming effect and the amount of polyelectrolyte, needed to achieve the same degree of structure-forming effect of soil dispersions. The causes for the revealed reasons are shown on the basis of the results of the experiment. Along with this, it was found that particular changes of structural composition and surface properties of the soil dispersions depend on the type and concentration of the added polyelectrolyte.

  12. Response of Swelling Behavior of Weak Branched Poly(ethylene imine)/Poly(acrylic acid) Polyelectrolyte Multilayers to Thermal Treatment.

    Science.gov (United States)

    Gu, Yuanqing; Weinheimer, Emily K; Ji, Xiang; Wiener, Clinton G; Zacharia, Nicole S

    2016-06-21

    Weak polyelectrolyte multilayers (PEMs) prepared by the layer-by-layer technique have attracted a great deal of attention as smart responsive materials for biological and other applications in aqueous medium, but their dynamic behavior as a function of exposure to a wide temperature range is still not well understood. In this work, the thermally dependent swelling behavior of PEMs consisting of branched poly(ethylenimine) and poly(acrylic acid) is studied by temperature controlled in situ spectroscopic ellipsometry. Because of diffusion and interpenetration of polyelectrolytes during film deposition, the PEMs densify with increasing bilayer number, which further affects their water uptake behavior. Upon heating to temperatures below 60 °C, the worsened solvent quality of the PEM in water causes deswelling of the PEMs. However, once heated above this critical temperature, the hydrogen bonds within the PEMs are weakened, which allows for chain rearrangement within the film upon cooling, resulting in enhanced water uptake and increased film thickness. The current work provides fundamental insight into the unique dynamic behavior of weak polyelectrolyte multilayers in water at elevated temperatures. PMID:27232180

  13. Selective surface functionalization of polystyrene induced by synchrotron or UV radiation in the presence of oxygen or acrylic acid vapors

    International Nuclear Information System (INIS)

    Efficient surface functionalization of Polystyrene (PS) thin films by electromagnetic radiation in combination with a reactive gaseous atmosphere was obtained. Monochromatic synchrotron (SR) or polychromatic UV radiation were used as excitation sources. When SR was used, O2 was introduced after irradiation into the UHV chamber. UV irradiation was carried out keeping a constant flow of O2 or acrylic acid (AA) vapors during the photolysis. FTIR-ATR and XPS-NEXAFS spectra were obtained at the UFRGS and the LNLS, Campinas respectively. PS films were functionalized by monochromatic SR and then expose to O2 at specific transitions such us C 1s →σ*C-C excitation. It was found a high rate of COO, C=O and C-O groups at the surface (> 70%). UV-assisted treatment in the presence of AA vapors showed that an efficient polymerization process took place, such as, it was observed in previous AA low pressure RF plasma treatments. UV-assisted functionalization has the advantage of lower costs and simple set-up compared to plasma treatments. (author)

  14. Enhancing antibiofouling performance of Polysulfone (PSf) membrane by photo-grafting of capsaicin derivative and acrylic acid

    Science.gov (United States)

    Wang, Jian; Sun, Haijing; Gao, Xueli; Gao, Congjie

    2014-10-01

    Biofouling is a critical issue in membrane water and wastewater treatment. Herein, antibiofouling PSf membrane was prepared by UV-assisted graft polymerization of acrylic acid (AA) and a capsaicin derivative, N-(5-methyl-3-tert-butyl-2-hydroxy benzyl) acrylamide (MBHBA), on PSf membrane. AA and MBHBA were used as hydrophilic monomer and antibacterial monomer separately. The membranes were characterized by FTIR-ATR, contact angle, SEM, AFM, cross-flow filtration unit, antifouling and antibacterial measurements. Verification of MBHBA and AA that photo-chemically grafted onto the PSf membrane surface is confirmed by carbonyl stretching vibration at ∼1655 cm-1 and ∼1730 cm-1, separately. The increasing AA concentration accelerates the graft-polymerization of MBHBA and resulted in a more hydrophilic surface. Consequently, antifouling property of the membranes was improved on a large level. The flux recovery rate can achieve 100% during the cyclic test, which may be attributed to the more hydrophilic and smooth surface, as well as the decreased membrane pore size. Most importantly, the presence of AA in graft co-polymer does not affect the antibacterial activity of MBHBA. That may be induced by the increasing chain length and flexibility of the grafted polymer chains.

  15. One step graft copolymerization of acrylic acid and sodium styrene sulfonate onto high-density polyethylene film by preirradiation method

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    High-density polyethylene (HDPE) films were irradiated by 60Co gamma ray with a dose of 100 kGy in air and then immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS) at different temperature. The effects of grafting conditions such as temperature, reaction time, Mohr's salt concentration, and total concentration of monomer on grafting yield were studied. Both grafting yield of AA and SSS onto HDPE respectively increases with total concentration of monomers. The highest grafting yield was observed at 3 mol/L monomers where the grafted PE swelled to the largest extent in the monomers mixture. The grafting yield increases with reaction time and then levels off. At higher temperature, the grafting yield decreases with Mohr's salt concentration, but increases at low temperature when Mohr's salt concentration is 0.083%. Which can be interpreted that in the presence of Fe2+ diperoxides and hydroperoxides may decompose at low temperature to form radical which can initiate the grafting. The physical and chemical properties of grafting films were also investigated.

  16. Removal of reactive dyes from textile wastewater by immobilized chitosan upon grafted Jute fibers with acrylic acid by gamma irradiation

    International Nuclear Information System (INIS)

    Jute fibers were grafted with acrylic acid by gamma irradiation technique. Chitosan was immobilized upon the grafted Jute fibers to be used as an adsorbent for waste reactive dye. The treated Jute fibers were characterized by using of Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effect of Jute treatment on its thermal stability by using thermogravimetric analysis (TGA) and its mechanical properties were investigated. The adsorption isotherm and the different factors affecting the dye adsorption such as pH and contact time were also studied. It was found that the dye adsorption was enhanced in the low pH range and increased with increasing of the contact time, regardless of temperature change. - Highlights: • Jute fibers were grafted by PAAc followed by immobilization with chitosan. • The treated Jute fibers were used as dye adsorbent from wastewater. • The different factors which affect the adsorption process were studied. • The higher adsorption capacity was achieved at low pH. • The treated Jute fibers can be used for three times after regeneration processes

  17. Synthesis and colon-specific drug delivery of a poly(acrylic acid-co-acrylamide)/MBA nanosized hydrogel.

    Science.gov (United States)

    Ray, Debajyoti; Mohapatra, Dillip K; Mohapatra, Ranjit K; Mohanta, Guru P; Sahoo, Prafulla K

    2008-01-01

    Intravenous administration of 5-fluorouracil (5-FU) for colon cancer therapy produces severe systemic side-effects due to its cytotoxic effect on normal cells. The main objective of the present study was to develop novel oral site-specific delivery of 5-FU to the colon with less drug being released in the stomach or small intestine using biodegradable hydrogel, hydrogel nanoparticles and comparing the targeting efficiency of 5-FU to colon from both. Poly(acrylic acid-co-acrylamide) (P(AA-co-Am)) normal hydrogel and hydrogel nanoparticles (HN) were synthesized by free radical polymerization using N,N-methylene-bis-acrylamide (MBA) as cross-linker, potassium persulfate as reaction initiator and 5-FU was loaded. HN were found to be degradable in physiological medium and showed comparatively higher swelling in rat caecal medium (RCM). 5-FU entrapment was increased by increasing Am (wt%) monomer feed. In vitro release of 5-FU from normal hydrogel and HN in pH progressive medium, it was found that a AA/Am ratio of 25:75 showed higher release in RCM. The Higuchi model yielded good adjustment of in vitro release kinetics. A higher amount of 5-FU reached the colon in HN (61 +/- 2.1%) than normal hydrogel (40 +/- 3.6%) by organ biodistribution studies in albino rats.

  18. TEMPERATURE AND pH RESPONSE, AND SWELLING BEHAVIOR OF POROUS ACRYLONITRILE-ACRYLIC ACID COPOLYMER HYDROGELS

    Institute of Scientific and Technical Information of China (English)

    Jian Huang; Zhi-ming Huang; Yong-zhong Bao; Zhi-xue Weng

    2006-01-01

    Macroporous acrylonitrile-acrylic acid (AN-AA) copolymer hydrogels were synthesized by free-radical solution polymerizations, using ammonium persulfate (APS)/N,N,N',N'-tetramethylethylenediamine (TEMED) redox initiator system and alcohols porogens. The morphology, temperature and pH sensitive swelling behavior, and swelling kinetics of the resulting hydrogels were investigated. It was found that alcohol type and concentration had great influences on the pore structure and porosity of hydrogels. The pore size of hydrogel increases with the moderate increase of the length of alcohol alkyl chain. However, a further increase of alkyl length would result in the formation of cauliflower-like structure and the decrease of pore size. The porosity of hydrogels increases with the increase of porogen concentration in the polymerization medium. The hydrogels with macroporous structure swell or shrink much faster in response to the change of pH in comparison with the conventional hydrogel without macroporous structure. Furthermore, the response rate is closely related to the porosity of the hydrogels, which could be easily controlled by modulating the concentration of the porogen in the medium. The circular swelling behavior of hydrogels indicated the formation of a relaxing three-dimensional network.

  19. Highly hydrophilic ultra-high molecular weight polyethylene powder and film prepared by radiation grafting of acrylic acid

    Science.gov (United States)

    Wang, Honglong.; Xu, Lu.; Li, Rong.; Pang, Lijuan.; Hu, Jiangtao.; Wang, Mouhua.; Wu, Guozhong.

    2016-09-01

    The surface properties of ultra-high molecular weight polyethylene (UHMWPE) are very important for its use in engineering or composites. In this work, hydrophilic UHMWPE powder and film were prepared by γ-ray pre-irradiation grafting of acrylic acid (AA) and further neutralization with sodium hydroxide solution. Variations in the chemical structure, grafting yield and hydrophilicity were investigated and compared. FT-IR and XPS analysis results showed that AA was successfully grafted onto UHMWPE powder and film; the powder was more suitable for the grafting reaction in 1 wt% AA solution than the film. Given a dose of 300 kGy, the grafting yield of AA was ∼5.7% for the powder but ∼0.8% for the film under identical conditions. Radiation grafting of a small amount of AA significantly improved the hydrophilicity of UHMWPE. The water contact angle of the UHMWPE-g-PAA powder with a grafting yield of AA at ∼5.7% decreased from 110.2° to 68.2°. Moreover, the grafting powder (UHMWPE-g-PAA) exhibited good dispersion ability in water.

  20. Assessment of multicomponent hydrogel scaffolds of poly(acrylic acid-2-hydroxy ethyl methacrylate)/gelatin for tissue engineering applications.

    Science.gov (United States)

    Jaiswal, Maneesh; Koul, Veena

    2013-03-01

    The article describes the design of the multicomponent hydrogel system of poly(acrylic acid-HEMA)/gelatin for tissue engineering application. Derivative of polycaprolactone-diol (polycaprolactone diacrylate (PCL-DAr)) was used to cross-link acrylate monomers whereas gelatin was kept free for cell proliferation. Epigallocatechin gallate (EGCG), an anti-oxidant phytochemical, was loaded by diffusion method. Its in vitro release study in PBS (pH 6.5) at 37 ± 0.2°C (75 rpm) revealed a sustained release profile upto 20 days. Fitting of drug release data in Korsmeyer-Peppas model equation revealed probable release mechanism through the value of release coefficient (n), which was found to depend on formulations composition. Drug-polymer interaction, thermal behavior, and surface morphology were investigated by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopic (SEM). Swelling behavior of hydrogel in PBS (pH 6.5 and 7.4, 0.2 M) and in distilled water was found to increase with increasing AAc/HEMA ratio. Compression modulus decreased from 203 ± 3.7 KPa to 11.6 ± 1.1KPa, at 30% strain, whereas displacement values significantly increased from 3.2 ± 0.2 to 4.7 ± 0.6 mm at 20 N force (p < 0.05), with increasing AAc/HEMA ratio. Percentage cell viability was analyzed using indirect 3-[4, 5-dimethylthiazolyl-2]-2,5-diphenyltetrazo-liumbromide (MTT) assay with fibroblast L929 cells; showed ≥92.3% cell viability after 24 h incubation. Cell proliferation on the scaffold surface was found to increase with incorporation of HEMA in P(AAc)/G cross-linked hydrogel matrix upto a certain extent. These biocompatible, elastic, and swellable hydrogels can serve as a matrix for drug delivery and tissue engineering applications.

  1. Extending framework based on the linear coordination polymers: Alternative chains containing lanthanum ion and acrylic acid ligand

    Science.gov (United States)

    Li, Hui; Guo, Ming; Tian, Hong; He, Fei-Yue; Lee, Gene-Hsiang; Peng, Shie-Ming

    2006-11-01

    One-dimensional alternative chains of two lanthanum complexes: [La( L1) 3(CH 3OH)(H 2O) 2]·5H 2O ( L1=anion of α-cyano-4-hydroxycinnamic acid ) 1 and [La( L2) 3(H 2O) 2]·3H 2O ( L2=anion of trans-3-(4-methyl-benzoyl)-acrylic acid) 2 were synthesized and structurally characterized by single-crystal X-ray diffraction, element analysis, IR and thermogravimetric analysis. The crystal structure data are as follows for 1: C 31H 36LaN 3O 17, triclinic, P-1, a=9.8279(4) Å, b=11.8278(5) Å, c=17.8730(7) Å, α=72.7960(10)°, β=83.3820(10)°, γ=67.1650(10)º, Z=2, R1=0.0377, wR2=0.0746; for 2: C 33H 37LaO 14, triclinic, P-1, a=8.7174(5) Å, b=9.9377(5) Å, c=21.153(2) Å, α=81.145(2)°, β=87.591(2)°, γ=67.345(5)°, Z=2, R1=0.0869, wR2=0.220. 1 is a rare example of the alternative chain constructed by syn-syn and anti-syn coordination mode of carboxylato ligand arranged along the chain alternatively. La(III) ions in 2 are linked by two η3-O bridges and four bridges (two η2-O and two η3-O) alternatively. Both of the linear coordination polymers grow into two- and three-dimensional networks by packing through extending hydrogen-bond network directed by ligands.

  2. Modification of Poly(Ethylene Terephthalate) Fiber by Grafting of Acrylic Acid/Acrylamide for Removal of Pb+2 from Aqueous Solutions

    International Nuclear Information System (INIS)

    A new fibrous adsorbent was prepared by grafting Acrylic Acid /Acryl Amide co-monomers onto Poly(Ethylene Terephthalate) fibers. The resulting sorbent has been characterized by Fourier Transform Infrared spectroscopy, Thermo Gravimetric Analysis, Scanning Electron Microscopy and elemental analysis and studied for the preconcentration and determination of trace Pb+2 ion from water sample. The effects of reaction conditions such as monomer mixture ratio, grafting yield, polymerization. The time and temperature on grafting were investigated. Batch adsorption method was used for the pre concentration studies. Recovery of Pb+2 was 100.2% at optimum conditions. The adsorption capacity of the adsorbent was found 44.1 mg/g for Pb+2.

  3. STUDY OF THE ADSORPTION PERFORMANCE OF STARCH GRAFTING ACRYLIC ACID ADSORBENT AGAINST Cr(Ⅵ)%淀粉接枝丙烯酸吸附剂对Cr(Ⅵ)吸附性能的研究

    Institute of Scientific and Technical Information of China (English)

    金漫彤

    2001-01-01

    本文主要研究了可溶性淀粉与丙烯酸聚合而制得的淀粉接枝丙烯酸,对重金属离子Cr(Ⅵ)的吸附效果及吸附条件。%The adsorption effect and conditions of starch-grafting acrylic Cr(Ⅵ) are studied in the paper, the strarch-grafting acrylic was preparcd by the polymurization of acrylic acid and pasterized solvable starch iniliated by potassium persulfate.

  4. Synthesis of Potato Starch-Acrylic-Acid Hydrogels by Gamma Radiation and Their Application in Dye Adsorption

    Directory of Open Access Journals (Sweden)

    Md. Murshed Bhuyan

    2016-01-01

    Full Text Available Several kinds of acrylic-acid-grafted-starch (starch/AAc hydrogels were prepared at room temperature (27°C by applying 5, 10, 15, 20, and 25 kGy of gamma radiation to 15% AAc aqueous solutions containing 5, 7.5, and 15% of starch. With increment of the radiation dose, gel fraction became higher and attained the maximum (96.5% at 15 kGy, above which the fraction got lowered. On the other hand, the gel fraction monotonically increased with the starch content. Swelling ratios were lower for the starch/AAc hydrogels prepared with higher gamma-ray doses and so with larger starch contents. Significant promotions of the swelling ratios were demonstrated by hydrolysis with NaOH: 13632±10% for 15 kGy radiation-dosed [5% starch/15% AAc] hydrogel, while the maximum swelling ratio was ~200% for those without the treatment. The authors further investigated the availability of the starch/AAc hydrogel as an adsorbent recovering dye waste from the industrial effluents by adopting methylene blue as a model material; the hydrogels showed high dye-capturing coefficients which increase with the starch ratio. The optimum dye adsorption was found to be 576 mg per g of the hydrogel having 7.5 starch and 15% AAc composition. Two kinetic models, (i pseudo-first-order and (ii pseudo-second-order kinetic models, were applied to test the experimental data. The latter provided the best correlation of the experimental data compared to the pseudo-first-order model.

  5. Self-assembled poly(ethylene glycol)-co-acrylic acid microgels to inhibit bacterial colonization of synthetic surfaces.

    Science.gov (United States)

    Wang, Qichen; Uzunoglu, Emel; Wu, Yong; Libera, Matthew

    2012-05-01

    We explored the use of self-assembled microgels to inhibit the bacterial colonization of synthetic surfaces both by modulating surface cell adhesiveness at length scales comparable to bacterial dimensions (∼1 μm) and by locally storing/releasing an antimicrobial. Poly(ethylene glycol) [PEG] and poly(ethylene glycol)-co-acrylic acid [PEG-AA] microgels were synthesized by suspension photopolymerization. Consistent with macroscopic gels, a pH dependence of both zeta potential and hydrodynamic diameter was observed in AA-containing microgels but not in pure PEG microgels. The microgels were electrostatically deposited onto poly(l-lysine) (PLL) primed silicon to form submonolayer surface coatings. The microgel surface density could be controlled via the deposition time and the microgel concentration in the parent suspension. In addition to their intrinsic antifouling properties, after deposition, the microgels could be loaded with a cationic antimicrobial peptide (L5) because of favorable electrostatic interactions. Loading was significantly higher in PEG-AA microgels than in pure PEG microgels. The modification of PLL-primed Si by unloaded PEG-AA microgels reduced the short-term (6 h) S. epidermidis surface colonization by a factor of 2, and the degree of inhibition increased when the average spacing between microgels was reduced. Postdeposition L5 peptide loading into microgels further reduced bacterial colonization to the extent that, after 10 h of S. epidermidis culture in tryptic soy broth, the colonization of L5-loaded PEG-AA microgel-modified Si was comparable to the very small level of colonization observed on macroscopic PEG gel controls. The fact that these microgels can be deposited by a nonline-of-sight self-assembly process and hinder bacterial colonization opens the possibility of modifying the surfaces of topographically complex biomedical devices and reduces the rate of biomaterial-associated infection. PMID:22519439

  6. The Chemical and Physical Properties of Poly(ε-caprolactone) Scaffolds Functionalised with Poly(vinyl phosphonic acid-co-acrylic acid).

    Science.gov (United States)

    Bassi, A K; Gough, J E; Zakikhani, M; Downes, S

    2011-01-01

    There is a clinical need for a synthetic alternative to bone graft substitute (BGS) derived from demineralised bone matrix. We report the electrospinning of Poly(ε-caprolactone) (PCL) to form a 3-dimensional scaffold for use as a synthetic BGS. Additionally, we have used Poly(vinyl phosphonic acid-co-acrylic acid) (PVPA) to improve bone formation. Fibres were formed using a 10% w/v PCL/acetone solution. Infrared spectroscopy confirmed that the electrospinning process had no effect on the functional groups present in the resulting structure. The electrospun scaffolds were coated with PVPA (PCL/PVPA), and characterised. The stability of the PVPA coating after immersion in culture medium was assessed over 21 days. There was rapid release of the coating until day 2, after which the coating became stable. The wettability of the PCL scaffolds improved significantly, from 123.3 ± 10.8° to 43.3 ± 1.2° after functionalisation with PVPA. The compressive strength of the PCL/PVPA scaffolds (72 MPa) was significantly higher to that of the PCL scaffold (14 MPa), and an intermediate between trabecular and cortical bone (7 MPa and 170 MPa, resp.). The study has demonstrated that the PCL/PVPA scaffold has the desired chemical and biomechanical characteristics required for a material designed to be used as a BGS. PMID:22073379

  7. Preparation of Poly Acrylic Acid-Poly Acrylamide Composite Nanogels by Radiation Technique

    Directory of Open Access Journals (Sweden)

    Parisa Ghorbaniazar

    2015-06-01

    Full Text Available Purpose: Nanogel, a nanoparticle prepared from a cross-linked hydrophilic polymer network, has many biomedical applications. A radiation technique has recently been introduced as one of the appropriate methods for the preparation of polymeric nanogels due to its additive-free initiation and easy control procedure. Methods: We have investigated the formation of nano-sized polymeric gels, based on the radiation-induced inter- and intra-molecular cross-linking of the inter-polymer complex (IPC of polyacrylamide (PAAm and polyacrylic acide (PAAc. Results: The results indicated that the prepared polymeric complex composed of PAAm and PAAc was converted into nanogel by irradiation under different doses (1, 3, 5 and 7 kGy. This was due to inter- and intra-molecular cross-linking at the range of 446-930 nm as characterized by the photon correlation spectroscopy method. Increasing the irradiation dose reduced the size of nanoparticles to 3 kGy; however, the higher doses increased the size and size distribution. Scanning electron microscopy images indicated the nanogel formation in the reported size by particle size and showed the microcapsule structure of the prepared nanogels. Biocompatibility of nanogels were assessed and proved by MTT assay. Conclusion: It was concluded that low dose irradiation can be successfully applied for nanometre-ranged hydrogel.

  8. Grafting Copolymerization of Styrene and Acrylic Acid onto Pre-irradiated Polypropylene Fabric%预辐射聚丙烯纤维接枝苯乙烯和丙烯酸的研究

    Institute of Scientific and Technical Information of China (English)

    陈捷; 杨黎明; 吴明红; 卢永畅

    2000-01-01

    Grafting copolymerization of styrene and acrylic acid onto polypropylene fabric had been studied by using a pre-irradiation technique. The polypropylene fabric samples were irradiated by γ -ray and electron beam under the conditions of air and nitrogen gas, respectively. The effect of absorbed dose, monomer concentration in solvent, reaction temperature and reaction time on the degree of grafting were determined. The effects of metallic salts and sulphuric acid on the grafting yield of acrylic acid were also examined. The samples irradiated by electron beam give a much higher degree of grafting than those by γ -ray when styrene was grafted to polypropylene fabric. However, the grafting yield of acrylic acid on polypropylene fabric in the presence of metallic salts and sulfuric acid showed the opposite results from the case of styrene. This effect is reasonably interpreted by assuming that the grafting is dominated by trapped radicals and peroxides in pre-irradiated polypropylene.

  9. Grafting Copolymerization of Styrene and Acrylic Acid onto Pre-irradiated Polypropylene Fabric%预辐射聚丙烯纤维接枝苯乙烯和丙烯酸的研究

    Institute of Scientific and Technical Information of China (English)

    陈捷; 杨黎明; 吴明红; 卢永畅

    2001-01-01

    Grafting copolymerization of styrene and acrylic acid onto polypropylene fabric had been studied by using a pre-irradiation technique. The polypropylene fabric samples were irradiated by γ -ray and electron beam under the conditions of air and nitrogen gas, respectively. The effect of absorbed dose, monomer concentration in solvent, reaction temperature and reaction time on the degree of grafting were determined. The effects of metallic salts and sulphuric acid on the grafting yield of acrylic acid were also examined. The samples irradiated by electron beam give a much higher degree of grafting than those by γ -ray when styrene was grafted to polypropylene fabric. However, the grafting yield of acrylic acid on polypropylene fabric in the presence of metallic salts and sulfuric acid showed the opposite results from the case of styrene. This effect is reasonably interpreted by assuming that the grafting is dominated by trapped radicals and peroxides in pre-irradiated polypropylene.

  10. Purification and preliminary characterization of (E)-3-(2,4-dioxo-6-methyl-5-pyrimidinyl)acrylic acid synthase, an enzyme involved in biosynthesis of the antitumor agent sparsomycin.

    Science.gov (United States)

    Parry, R J; Hoyt, J C

    1997-02-01

    Sparsomycin is an antitumor antibiotic produced by Streptomyces sparsogenes. Biosynthetic experiments have previously demonstrated that one component of sparsomycin is derived from L-tryptophan via the intermediacy of (E)-3-(4-oxo-6-methyl-5-pyrimidinyl)acrylic acid and (E)-3-(2,4-dioxo-6-methyl-5-pyrimidinyl)acrylic acid. An enzyme which catalyzes the conversion of (E)-3-(4-oxo-6-methyl-5-pyrimidinyl)acrylic acid to (E)-3-(2,4-dioxo-6-methyl-5-pyrimidinyl)acrylic acid has been purified 740-fold to homogeneity from S. sparsogenes. The molecular mass of the native and denatured enzyme was 87 kDa, indicating that the native enzyme is monomeric. The enzyme required NAD+ for activity but lacked rigid substrate specificity, since analogs of both NAD+ and 3-(4-oxo-6-methyl-5-pyrimidinyl)acrylic acid could serve as substrates. The enzyme was very weakly inhibited by mycophenolic acid. Monovalent cations were required for activity, with potassium ions being the most effective. The enzyme exhibited sensitivity toward diethylpyrocarbonate and some thiol-directed reagents, and it was irreversibly inhibited by 6-chloropurine. The properties of the enzyme suggest it is mechanistically related to inosine-5'-monophosphate dehydrogenase. PMID:9023226

  11. Superabsorbent hydrogels via graft polymerization of acrylic acid from chitosan-cellulose hybrid and their potential in controlled release of soil nutrients.

    Science.gov (United States)

    Essawy, Hisham A; Ghazy, Mohamed B M; El-Hai, Farag Abd; Mohamed, Magdy F

    2016-08-01

    Superabsorbent polymers fabricated via grafting polymerization of acrylic acid from chitosan (CTS) yields materials that suffer from poor mechanical strength. Hybridization of chitosan with cellulose (Cell) via chemical bonding using thiourea formaldehyde resin increases the flexibility of the produced hybrid (CTS/Cell). The hybridization process and post graft polymerization of acrylic acid was followed using Fourier transform infrared (FTIR). Also, the obtained structures were homogeneous and exhibited uniform surface as could be shown from imaging with scanning electron microscopy (SEM). Thus, the polymers derived from the grafting of polyacrylic acid from (CTS/Cell) gave rise to much more mechanically robust structures ((CTS/Cell)-g-PAA) that bear wide range of pH response due to presence of chitosan and polyacrylic acid in one homogeneous entity. Additionally, the obtained structures possessed greater water absorbency 390, 39.5g/g in distilled water and saline (0.9wt.% NaCl solution), respectively, and enhanced retention potential even at elevated temperatures as revealed by thermogravimetric analysis (TGA). This could be explained by the high grafting efficiency (GE%), 86.4%, and grafting yield (GY%), 750%. The new superabsorbent polymers proved to be very efficient devices for controlled release of fertilizers into the soil which expands their use in agriculture and horticultural applications. PMID:27126169

  12. Synthesis of interpenetrating network hydrogel from poly(acrylic acid-co-hydroxyethyl methacrylate) and sodium alginate: modeling and kinetics study for removal of synthetic dyes from water.

    Science.gov (United States)

    Mandal, Bidyadhar; Ray, Samit Kumar

    2013-10-15

    Several interpenetrating network (IPN) hydrogels were made by free radical in situ crosslink copolymerization of acrylic acid (AA) and hydroxy ethyl methacrylate in aqueous solution of sodium alginate. N,N'-methylenebisacrylamide (MBA) was used as comonomer crosslinker for making these crosslink hydrogels. All of these hydrogels were characterized by carboxylic content, FTIR, SEM, XRD, DTA-TGA and mechanical properties. Swelling, diffusion and network parameters of the hydrogels were studied. These hydrogels were used for adsorption of two important synthetic dyes, i.e. Congo red and methyl violet from water. Isotherms, kinetics and thermodynamics of dye adsorption by these hydrogels were also studied.

  13. Usefulness of microporous hydrophobic polypropylene membranes after plasma-induced graft polymerization of acrylic acid for high-power nickel-cadmium batteries

    International Nuclear Information System (INIS)

    Commercial microporous polypropylene (PP) membranes were modified by plasma-induced graft polymerization of acrylic acid (AAc) under UV irradiation. Under optimized conditions obtained membranes are hydrophilic and may be serviceable as separator in nickel-cadmium cell. Electrolytic resistance of modified membranes is evaluated and compared with that of commercial separators: conventional cellophane separation and hydrophilic polypropylene separation (Celgard 3501). This paper reports the maximum power test data for nickel-cadmium cells equipped with different separators. Cells with modified PP membrane show very good high-rate performance

  14. Development of a platform for nasal delivery of peptides and vaccines using powder carriers based on starch/poly(acrylic) acid

    OpenAIRE

    Coucke, Delphine

    2009-01-01

    The interest in and importance of systemic drug delivery via the nasal route have expanded in recent decades since nasal administration offers an interesting alternative for the conventional oral and parenteral drug delivery routes. In this thesis, the nasal route was selected as an alternative route for peptide and vaccine delivery. A spray-dried combination of maize starch (Amioca®) and a cross-linked acrylic acid-based polymer (Carbopol® 974P) was used as powder carrier to amplify the ...

  15. Synthesis of polyaniline catalysed by Cu(I), Ni(II) and Fe(II) supported on the polyethylene-i-acrylic acid copolymer

    International Nuclear Information System (INIS)

    In this study the active sites of acrylic acid (AA) were grafted in low density polyethylene (PEBD) using gamma radiation. Subsequently, the graft copolymer PEBD-i-AA was coordinated with different metals such as copper, nickel and iron. The organometallic copolymers so formed were used as catalysts in the aniline polymerization reaction. Finally, it was realized the characterization of the obtained products, determining their thermal properties, copolymer graft percentage, quantification of the metal contained in the complex as well as polymerization and electric conductivity percentages of the poly aniline film. (Author)

  16. Surface modification of aramid fiber by plasma induced vapor phase graft polymerization of acrylic acid. I. Influence of plasma conditions

    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); School of Textile and Clothing, Nantong University, Jiangsu 226019 (China); Du, M. [College of Textiles and Clothing, Yancheng Institute of Industry Technology, Jiangsu 224000 (China); Lv, J.C.; Zhou, Q.Q. [College of Textiles and Clothing, Yancheng Institute of Technology, Jiangsu 224003 (China); Ren, Y. [School of Textile and Clothing, Nantong University, Jiangsu 226019 (China); Liu, G.L.; Gao, D.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)

    2015-09-15

    Highlights: • Aramid fiber surface was modified by PIVPGP of AA to improve wettability, adhesion. • Surface modification effect by PIVPGP of AA increased and then decreased with time. • Surface modification effect increased and then stayed unaltered with output power. • Ar plasma was the most effective in PIVPGP of AA on aramid fiber surface. • In studied range, optimum technology of PIVPGP of AA: Ar plasma, 15 min, 300 W. - Abstract: Plasma induced vapor phase graft polymerization (PIVPGP) method was applied to modify aramid fiber surface. In this study, aramid fibers were pretreated under various plasma conditions such as different treatment times, output powers and working gases to see how these plasma processing parameters influenced the PIVPGP of acrylic acid (AA) on aramid fiber surface and its surface structure and properties. The analysis results of atomic force microscope (AFM) and X-ray photoelectron spectroscope (XPS) showed the increase of surface roughness and the introduction of O=C−OH, which confirmed that the PIVPGP of AA on aramid fiber surface was achieved. The contact angle and interfacial shear strength (IFSS) of the aramid fibers modified by PIVPGP of AA prominently decreased and increased, respectively, indicating the obvious improvements of surface wettability and adhesion between aramid fiber and matrix. The surface modification effects of aramid fiber by PIVPGP of AA firstly increased and then after 15 min slightly decreased with the increasing plasma treatment time, and but firstly increased and then after 300 W nearly remained unchanged with the increasing output power, respectively. Among different working gases, Ar plasma occupied first place, O{sub 2} plasma and N{sub 2} plasma came second and third in the aspect of PIVPGP of AA on aramid fiber surface, respectively. It could be concluded that the PIVPGP of AA on aramid fiber surface could effectively improve surface wettability and adhesion. Plasma conditions had signally

  17. Effect of chemical composition on corneal tissue response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jui-Yang, E-mail: jylai@mail.cgu.edu.tw

    2014-01-01

    The purpose of this work was to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and hydrogel material compatibility towards ocular anterior segment tissues, particularly the corneal endothelium. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Then, the 7-mm-diameter membrane implants made from photopolymerized materials were placed into the ocular anterior chamber for 4 days and assessed by biomicroscopic examinations, corneal thickness measurements, and quantitative real-time reverse transcription polymerase chain reaction analyses. The poly(HEMA-co-AAc) implants prepared from the solution mixture containing 0–10 vol.% AAc displayed good biocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the enhanced inflammatory response, decreased endothelial cell density, and increased ocular score and corneal thickness were observed, probably due to the influence of surface charge of copolymer membranes. On the other hand, the ionic pump function of corneal endothelium exposed to photopolymerized membranes was examined by analyzing the Na{sup +},K{sup +}-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of the implants having higher amount of AAc incorporated in the copolymers (i.e., 15.1 to 24.7 μmol) and zeta potential (i.e., -38.6 to − 56.5 mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal tissue responses to polymeric biomaterials. - Highlights: • We examine the corneal tissue responses to photopolymerized biomaterials. • Carboxyl groups in copolymers increased with increasing volume ratio of AAc/HEMA. • 15–20 vol.% AAc raised ocular score and caused corneal endothelial loss and edema. • High anionic charge density stimulated inflammation

  18. Effect of chemical composition on corneal cellular response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jui-Yang, E-mail: jylai@mail.cgu.edu.tw

    2013-10-15

    Characterization of corneal cellular response to hydrogel materials is an important issue in ophthalmic applications. In this study, we aimed to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and material compatibility towards corneal stromal and endothelial cells. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Results of electrokinetic measurements showed that an increase in absolute zeta potential of photopolymerized membranes is observed with increasing the volume ratios of AAc/HEMA. Following 4 days of incubation with various hydrogels, the primary rabbit corneal stromal and endothelial cell cultures were examined for viability, proliferation, and pro-inflammatory gene expression. The samples prepared from the solution mixture containing 0–10 vol.% AAc displayed good cytocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the decreased viability, inhibited proliferation, and stimulated inflammation were noted in both cell types, probably due to the stronger charge–charge interactions. On the other hand, the ionic pump function of corneal endothelial cells exposed to photopolymerized membranes was examined by analyzing the Na{sup +},K{sup +}-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of material samples having higher anionic charge density (i.e., zeta potential of − 38 to − 56 mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal stromal and endothelial cell responses to polymeric biomaterials. - Highlights: • We examine the corneal cellular responses to photopolymerized biomaterials. • Charge density of membranes was increased with increasing volume ratio of AAc/HEMA. • 15–20 vol.% AAc decreased viability and proliferation

  19. Acrylates and methacrylates of formal-glycerine

    International Nuclear Information System (INIS)

    Present article is devoted acrylates and methacrylates of formal-glycerine. The formal-glycerine was obtained in the form of mixture of isomers 1.2 and 1.3 from glycerine and paraform with hydrochloric acid. The structure of obtained acrylates and methacrylates is studied by means of molecular refraction, element analysis and infrared spectroscopy.

  20. Studies on Micellization of a Polystyrene-b-poly(acrylic acid) Copolymer in Aqueous Media by Pyrene Fluorescence

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Pyrcnc probc and TEM have been employed to investigate the behavior of a polystyrenc-b-poly(acrylic aeid) (PS-b-PAA) copolymer in aqueous solution. A significant annealing temperature effect on the I1/I3 ratio of pyrene was observed and was interpreted in terms ofthe morphological change ofmicellar cores. Anncaling at a temperature higher than the glass transition temperature (Tg) of PS leads to densification ofthe hydrophobic core.

  1. Synthesis and characterization of antigenic influenza A M2e protein peptide-poly(acrylic) acid bioconjugate and determination of toxicity in vitro.

    Science.gov (United States)

    Kilinc, Yasemin Budama; Akdeste, Zeynep Mustafaeva; Koc, Rabia Cakir; Bagirova, Melahat; Allahverdiyev, Adil

    2014-01-01

    The influenza A virus is a critical public health problem that causes epidemics and pandemics, and occurs widely all over the world. Various vaccines against the virus have not provided a solution to the problem. Different approaches, particularly M2e peptide-based vaccines, are available for developing universal vaccines against influenza A. However, it is important to select a suitable carrier to obtain an effective vaccine. Accordingly, studies on the usage of various carriers are ongoing. Particularly, polymer-based carriers have gained importance due to both drug delivery and adjuvant effects. Therefore, bioconjugate of the M2e protein peptide from the influenza A virus covalent bonded with poly(acrylic) acid was synthesized in our study for the first time. The characterization was performed using size-exclusion chromatography and fluorescence spectroscopy; subsequently, it was found that the bioconjugate of the examined lower doses (0.05 and 0.5 mg/ml) have no toxic effects on human cell lines. These results suggest that, in the future, the poly(acrylic) acid bioconjugate of the M2e peptide should be studied in vivo for universal vaccine development against the influenza A virus. PMID:25482080

  2. Magnetic Solid-Phase Extraction Based on β-Cyclodextrins/Acrylic Acid Modified Magnetic Gelatin for Determination of Moxidectin in Milk Samples

    Directory of Open Access Journals (Sweden)

    Yinzhu Shang

    2016-01-01

    Full Text Available β-Cyclodextrins/acrylic acid modified magnetic gelatin was prepared and then employed as the magnetic solid-phase extraction (MSPE sorbent for extraction of moxidectin in milk samples. Due to the rigidity of hydrophobic cavity of β-cyclodextrins and carboxyl groups of acrylic acid, magnetic composites are prepared to form a complex with target molecules through various kinds of chemical reactions and then showed excellent extraction performance. This method exhibits the advantages of simplicity of implementation, short extraction time (5 min, low solvent consumption, and high extraction efficiency. A rapid, simple, and effective method for the analysis of moxidectin in milk samples was established by MSPE coupled with liquid chromatography-fluorescence detection. The limit of detection was 0.1 ng·mL−1 and the recoveries from milk samples were in the range of 93.8%–112.5%. The relative standard deviation was not higher than 6.4%. In conclusion, magnetic solid-phase extraction is a simple and robust preconcentration technique that can be coupled to other analytical methods for the quantitative determination of target molecules in complex samples.

  3. Magnetic Solid-Phase Extraction Based on β-Cyclodextrins/Acrylic Acid Modified Magnetic Gelatin for Determination of Moxidectin in Milk Samples

    Science.gov (United States)

    Shang, Yinzhu; Wang, Peng; Zhao, Xiaoya; Ye, Cheng; Guo, Shaofei

    2016-01-01

    β-Cyclodextrins/acrylic acid modified magnetic gelatin was prepared and then employed as the magnetic solid-phase extraction (MSPE) sorbent for extraction of moxidectin in milk samples. Due to the rigidity of hydrophobic cavity of β-cyclodextrins and carboxyl groups of acrylic acid, magnetic composites are prepared to form a complex with target molecules through various kinds of chemical reactions and then showed excellent extraction performance. This method exhibits the advantages of simplicity of implementation, short extraction time (5 min), low solvent consumption, and high extraction efficiency. A rapid, simple, and effective method for the analysis of moxidectin in milk samples was established by MSPE coupled with liquid chromatography-fluorescence detection. The limit of detection was 0.1 ng·mL−1 and the recoveries from milk samples were in the range of 93.8%–112.5%. The relative standard deviation was not higher than 6.4%. In conclusion, magnetic solid-phase extraction is a simple and robust preconcentration technique that can be coupled to other analytical methods for the quantitative determination of target molecules in complex samples. PMID:27437160

  4. Spray-dried powders of starch and crosslinked poly(acrylic acid) as carriers for nasal delivery of inactivated influenza vaccine.

    Science.gov (United States)

    Coucke, D; Schotsaert, M; Libert, C; Pringels, E; Vervaet, C; Foreman, P; Saelens, X; Remon, J P

    2009-02-18

    Mucosal vaccination has several advantages over parenteral vaccination. In this study, viscosity-enhancing mucosal delivery systems for the induction of an adaptive immune response against viral antigen were investigated. Powder formulations based on spray-dried mixtures of starch (Amioca)/poly(acrylic acid) (Carbopol 974P) in different ratios were used as carriers of the viral antigen. A comparison of these formulations for intranasal delivery of heat-inactivated influenza virus combined with LTR192G adjuvant was made in vivo in a rabbit model. Individual rabbit sera were tested for seroconversion against hemagglutinin (HA), the major surface antigen of influenza. The powder vaccine formulations were able to induce systemic anti-HA IgG responses. The presence of Carbopol 974P improved the kinetics of the immune responses and the level of IgG titers in a dose-dependent way which was correlated with moderately irritating capacities of the formulation. In contrast, mucosal IgA responses were not detected. In conclusion, it was demonstrated that the use of bioadhesive carriers based on Amioca starch and poly(acrylic acid) facilitates the induction of a systemic anti-HA antibody response after intranasal vaccination with a whole virus influenza vaccine. PMID:19114075

  5. Synthesis and magnetic heating characteristics of thermoresponsive poly (N-isopropylacrylamide-co-acrylic acid)/nano Fe3O4 nanparticles

    Science.gov (United States)

    Thu Trang Mai, Thi; Le, Thi Hong Phong; Pham, Hong Nam; Do, Hung Manh; Phuc Nguyen, Xuan

    2014-12-01

    In this work the synthesis of thermo-sensitive polymer coated magnetic nanoparticles and their inductive heating have been studied. Poly (N-isopropylacrylamide-co-acrylic acid) (NA) polymers were first synthesized by emulsion polymerization of poly(N-isopropylacrylamide) (NIP) in water and followed by encapsulating magnetic nanoparticles (MNPs). As increasing the concentration of acrylic acid (AA), the lower critical solution temperature (LCST) increased, so that with 150% of AA (molar ratio) the LCST reached 42 °C, which is close to the temperature of hyperthermia treatment. Magnetization and ac susceptibility measurements were conducted to depict some characteristics of the NIP-MNPs and NA-MNPs that are related with the loss power. Attempts to analyze the rate of magnetic inductive heating were performed to show the Brownian relaxation origin of additional heat source created by the magnetite nanoparticles capped with thermosensitive polymers. Our results suggest that these thermo-sensitive polymer-coated magnetic nanoparticles show a potential for hyperthermia and drug delivery application.

  6. Effect of Mole Percentage of Crosslinker of Silver-poly(N-isopropylacrylamide-co-acrylic acid Hybrid Microgels on Catalytic Reduction of Nitrobenzene

    Directory of Open Access Journals (Sweden)

    Zahoor H. FAROOQI

    2015-02-01

    Full Text Available Poly(N-isopropylacrylamide-co-acrylic acid microgels [P(NIPAM-co-AAc] with 2, 4, 6 and 8 mole percentage of N,N-methylene-bis-acrylamide were used as micro-reactors for the fabrication of Ag nanoparticles using the in situ reduction method. The pure and hybrid microgels were characterized by Fourier transform infrared and Ultraviolet-Visible spectroscopies. Silver-poly(N-isopropylacrylamide-co-acrylic acid hybrid microgels [Ag-P(NIPAM-co-AAc] with different crosslinker contents were used as catalysts for reduction of nitrobenzene (NB in aqueous medium in order to investigate the effect of crosslinker content on the value of apparent rate constant (kapp. 0.041, 0.146, 0.2388 and 0.255 min-1 were found as values of kapp for catalytic reduction of NB using hybrid microgels with 2, 4, 6 and 8 mole percentage of crosslinker, respectively. The effect of crosslinker feed content of hybrid microgels on catalytic activity for reduction of NB was compared to that of reduction of p-nitrophenol in aqueous medium.

  7. Synthesis of lithium iron phosphate/carbon microspheres by using polyacrylic acid coated iron phosphate nanoparticles derived from iron(III) acrylate.

    Science.gov (United States)

    Xu, Dongwei; He, Yan-Bing; Chu, Xiaodong; Ding, Zhaojun; Li, Baohua; He, Jianfu; Du, Hongda; Qin, Xianying; Kang, Feiyu

    2015-03-01

    Lithium iron phosphate/carbon (LiFePO4 /C) microspheres with high rate and cycling performance are synthesized from iron phosphate/polyacrylic acid (FePO4 /PAA) nanoparticles. Iron(III) acrylate is used as a precursor for both the iron and carbon sources. FePO4 nanoparticles are first produced by a coprecipitation reaction. The byproduct, acrylic acid ions, is polymerized in situ to form a uniform PAA layer on the surface of the FePO4 nanoparticles. The as-prepared LiFePO4 /C microspheres are composed of primary nanoparticles with sizes of 40-50 nm. The nanoparticles are fully coated with a thin, uniform carbon layer derived from the decomposition of the PAA layer. The uniform carbon-coating layer cooperates with interstitial and boundary carbon derived from sucrose successfully to construct an excellent interconnecting conductive network in the microspheres. As a result of the unique structure, the as-prepared LiFePO4 /C microspheres display both high electronic and ionic conductivities, which contribute to their high rate performance (162.9 mAh g(-1) at 0.1C and 126.1 mAh g(-1) at 5C) and excellent cycling stability (97.1% of capacity retention after 500 cycles at 5C/5C).

  8. STUDY ON POLYMER-RARE EARTH METAL ION COMPLEXES I. FLUORESCENT PROPERTIES OF POLY(ACRYLIC ACID-CO-4-VINYLPYRIDINE)-RARE EARTH METAL COMPLEXES

    Institute of Scientific and Technical Information of China (English)

    LU Hong; FANG Shibi; JIANG Yingyan

    1987-01-01

    A kind of copolymer of acrylic acid and vinylpyridine was synthesized and the fluorescent properties of the complexes of the copolymer with Eu3+ or Tb3+ were studied. It was found that the fluorescence intensity of the complexes of the copolymer with Eu3+ was 20 times as high as that of the complexes of polyacrylic acid with Eu3+ and twice as high as that of the complexes of polyvinylpyridine with Eu3+. The effects of the composition of the copolymer and the content of Eu3+ or Tb3+ in the complexes were studied.The fluorescence lifetime of the complexes was measured and it was found that two or more kinds of energy transfer mechanism existed.

  9. Time-resolved EPR investigation of potential model systems for acrylate polymer main chain radicals based on esters of Kemp's tri-acid.

    Science.gov (United States)

    Lebedeva, Natalia V; Gorelik, Elena V; Magnus-Aryitey, Damaris; Hill, Terence E; Forbes, Malcolm D E

    2009-05-14

    Methyl esters of Kemp's tri-acid and cyclohexanetricarboxylic acid are structurally similar to acrylate polymers, having the same functionalities and stereoregularities as poly(methylmethacrylate) and poly(methylacrylate), respectively. The photochemistry and free radicals from these model systems have been studied using time-resolved electron paramagnetic resonance spectroscopy with laser flash photolysis at 248 nm. Chemically induced electron spin polarization from the triplet mechanism (net emission) is observed. Well-resolved spectra are obtained at all temperatures for the model system radicals, which are determined to be in the slow motion condition, that is, there is no interconversion of chair conformations. The temperature dependence of the spectra is minimal; some hyperfine lines shift as the temperature increases, but without much broadening. Density functional theory calculations are presented and discussed in support of the experimental data.

  10. Neutral, anionic, cationic, and zwitterionic diblock copolymers featuring poly(2-methoxyethyl acrylate) hydrophobic segments

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Jankova Atanasova, Katja; Hvilsted, Søren

    2013-01-01

    Amphiphilic diblock copolymers incorporating hydrophobic poly(2-methoxyethyl acrylate) (PMEA) and hydrophilic neutral poly(ethylene glycol) monomethyl ether (mPEG), anionic poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMAA), cationic poly(2-dimethylaminoethyl methacrylate) (PDMAEMA...

  11. Separation of poly(acrylic acid) salts according to topology using capillary electrophoresis in the critical conditions.

    Science.gov (United States)

    Maniego, Alison R; Ang, Dale; Guillaneuf, Yohann; Lefay, Catherine; Gigmes, Didier; Aldrich-Wright, Janice R; Gaborieau, Marianne; Castignolles, Patrice

    2013-11-01

    Branching was detected in polyacrylates synthesised through radical polymerization via solution-state NMR, while inconsistencies have been reported for the determination of the molar mass of hydrophilic polyacrylates using aqueous-phase and organic-phase size-exclusion chromatography. In this work, poly(sodium acrylate)s, PNaAs, of various topologies were separated for the first time using free-solution capillary electrophoresis (CE). Free-solution CE does not separate the PNaAs by their molar mass, similarly to separations by liquid chromatography in the critical conditions, rather by different topologies (linear, star branched, and hyperbranched). The electrophoretic mobility of PNaAs increases as the degree of branching decreases. Separation is shown to be not only by the topology but also by the end groups as expected for a separation in the critical conditions: replacing a relatively bulky nitroxide end group with hydrogen atom yielded a higher electrophoretic mobility. This novel method, capillary electrophoresis in the critical conditions enabled, for the first time, the separation of hydrophilic polyacrylates according to their topology (branching) and their chain ends. This will allow meaningful and accurate characterization of their branched topologies as well as molar masses and progress in for advanced applications such as drug delivery or flocculation. PMID:23732867

  12. A Novel Route for Preparing Highly Stable Fe3O4 Fluid with Poly(Acrylic Acid) as Phase Transfer Ligand

    Science.gov (United States)

    Oanh, Vuong Thi Kim; Lam, Tran Dai; Thu, Vu Thi; Lu, Le Trong; Nam, Pham Hong; Tam, Le The; Manh, Do Hung; Phuc, Nguyen Xuan

    2016-08-01

    Highly stable Fe3O4 liquid was synthesized by thermal decomposition using poly(acrylic acid) (PAA) as a phase transfer ligand. The crystalline structure, morphology, and magnetic properties of the as-prepared samples were thoroughly characterized. Results demonstrated that the magnetic Fe3O4 nanomaterial was formed in liquid phase with a spinel single-phase structure, average size of 8-13 nm, and high saturation magnetization (up to 75 emu/g). The PAA-capped Fe3O4 nanoparticles displayed high stability over a wide pH range (from 4 to 7) in 300 mM salt solution. More importantly, the heat-generating capacity of the nanoparticle systems was quantified at a specific absorption rate (SAR) of 70.22 W/g, which is 35% higher than magnetic nanoparticles coated with sodium dodecyl sulfate (SDS). These findings suggest the potential application of PAA-coated magnetic nanoparticles in magnetic hyperthermia.

  13. The use of dielectric spectroscopy for the characterisation of the precipitation of hydrophobically modified poly(acrylic-acid) with divalent barium ions

    DEFF Research Database (Denmark)

    Christensen, Peter Vittrup; Keiding, Kristian

    2009-01-01

    The use of dielectric spectroscopy as a monitor for coagulation processes was investigated. Hydrophobically modified poly(acrylic-acid) polymers were used as model macromolecules and coagulated with barium ions. The coagulation process was quantified using a photometric dispersion analyser, thereby...... serving as a point of reference for the dielectric spectroscopy. It was found that the hydrophobic modification increased the dosage of barium needed to obtain complete coagulation, whereas the dosage required to initiate coagulation was lowered. The coagulation of the polymer samples caused...... the relaxation time of the measured dielectric dispersion to increase, and this parameter was found to be a good indicator of the formation of polymer aggregates. The magnitude of the dielectric dispersion decreased as a function of barium dosage, but when coagulation was initiated an increase was observed...

  14. Preparation of porous carboxymethyl chitosan grafted poly (acrylic acid) superabsorbent by solvent precipitation and its application as a hemostatic wound dressing.

    Science.gov (United States)

    Chen, Yu; Zhang, Yong; Wang, Fengju; Meng, Weiwei; Yang, Xinlin; Li, Peng; Jiang, Jianxin; Tan, Huimin; Zheng, Yongfa

    2016-06-01

    The volume phase transition of a hydrogel initiated by shrinking may result in complex patterns on its surface. Based on this unique property of hydrogel, we have developed a novel solvent precipitation method to prepare a kind of novel superabsorbent polymers with excellent hemostatic properties. A porous carboxymethyl chitosan grafted poly (acrylic acid) (CMCTS-g-PAA) superabsorbent polymer was prepared by precipitating CMCTS-g-PAA hydrogel with ethanol. Its potential application in hemostatic wound dressing was investigated. The results indicate that the modified superabsorbent polymer is non-cytotoxic. It showed a high swelling capacity and better hemostatic performance in the treatments of hemorrhage model of ear artery, arteria cruralis and spleen of the New Zealand white rabbit than the unmodified polymer and other commonly used clinic wound dressings. The hemostatic mechanism of the porous CMCTS-g-PAA polymer was also discussed. PMID:27040191

  15. Surfactant mediated synthesis of poly(acrylic acid) grafted xanthan gum and its efficient role in adsorption of soluble inorganic mercury from water.

    Science.gov (United States)

    Pal, Abhijit; Majumder, Kunal; Bandyopadhyay, Abhijit

    2016-11-01

    Noble copolymers from xanthan gum (XG) and poly(acrylic acid) (PAA) were synthesised through surfactant mediated graft copolymerization. The copolymers were applied as a biosorbent for inorganic Hg(II) at higher concentration level (300ppm). The copolymers were characterized using different analytical techniques which showed, the grafting principally occurred across the amorphous region of XG. Measurement of zeta potential and hydrodynamic size indicated, the copolymers were strong polyanion and possessed greater hydrodynamic size (almost in all cases) than XG, despite a strong molecular degradation that took place simultaneously during grafting. In the dispersed form, all grades of the copolymer displayed higher adsorption capability than XG, however, the grade with maximum grafting produced the highest efficiency (68.03%). Manipulation produced further improvement in efficiency to 72.17% with the same copolymer after 75min at a pH of 5.0. The allowable biosorbent dose, however, was 1000ppm as determined from the experimental evidences. PMID:27516248

  16. SELECTIVE SEPARATION OF WATER-ETHANOL MIXTURES THROUGH COPOLYMERIC MEMBRANES:Ⅰ. ACRYLIC ACID AND ACRYLONITRILE COPOLYMER AND ITS IONIZED MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fuyao; ZHANG Yifeng; ZHAO Zhuomin; SHEN Zhiquan

    1993-01-01

    The copolymer of acrylic acid and acrylonitrile has been synthesized and pervaporation properties of the copolymeric membranes have been investigated. In order to elucidate the influence of membrane-permeate interaction on the pervaporation of water-ethanol mixtures and to prepare much improved membranes, the membranes have been treated with alkali metal, alkali earth metal and transition metal salt aqueous solutions. The treated membranes (ionized membranes)exhibited higher separation factors than the untreated membranes. The separation factors of various alkali metal cation membranes decreased in the following order: Li+>Na+>K+, and the permeation rates showed an opposite tendency. The dependence of pervaporation behavior on the copolymer composition ,feed concentration and operating temperature have been studied with both ionized and non-ionized membranes. The apparent activation energies of water and ethanol permeation were calculated.

  17. Hybrid polymeric hydrogels for ocular drug delivery: nanoparticulate systems from copolymers of acrylic acid-functionalized chitosan and N-isopropylacrylamide or 2-hydroxyethyl methacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Barbu, Eugen; Tsibouklis, John [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth PO1 2DT (United Kingdom); Verestiuc, Liliana [Faculty of Medical Bioengineering, University of Medicine and Pharmacy ' Gr T Popa' , 9-13 Kogalniceanu Street, Iasi, 700454 (Romania); Iancu, Mihaela; Jatariu, Anca [Faculty of Chemical Engineering and Environmental Protection, Technical University' Gh Asachi' , Boulevard Mangeron, 71A, 700100, Iasi (Romania); Lungu, Adriana [Faculty of Applied Chemistry and Materials Science, Polytechnic University of Bucharest, Polizu Street 1-7, 011061, Bucharest (Romania)], E-mail: eugen@barbu@port.ac.uk

    2009-06-03

    Nanoparticulate hybrid polymeric hydrogels (10-70 nm) have been obtained via the radical-induced co-polymerization of acrylic acid-functionalized chitosan with either N-isopropylacrylamide or 2-hydroxyethyl methacrylate, and the materials have been investigated for their ability to act as controlled release vehicles in ophthalmic drug delivery. Studies on the effects of network structure upon swelling properties, adhesiveness to substrates that mimic mucosal surfaces and biodegradability, coupled with in vitro drug release investigations employing ophthalmic drugs with differing aqueous solubilities, have identified nanoparticle compositions for each of the candidate drug molecules. The hybrid nanoparticles combine the temperature sensitivity of N-isopropylacrylamide or the good swelling characteristics of 2-hydroxyethyl methacrylate with the susceptibility of chitosan to lysozyme-induced biodegradation.

  18. Hybrid polymeric hydrogels for ocular drug delivery: nanoparticulate systems from copolymers of acrylic acid-functionalized chitosan and N-isopropylacrylamide or 2-hydroxyethyl methacrylate.

    Science.gov (United States)

    Barbu, Eugen; Verestiuc, Liliana; Iancu, Mihaela; Jatariu, Anca; Lungu, Adriana; Tsibouklis, John

    2009-06-01

    Nanoparticulate hybrid polymeric hydrogels (10-70 nm) have been obtained via the radical-induced co-polymerization of acrylic acid-functionalized chitosan with either N-isopropylacrylamide or 2-hydroxyethyl methacrylate, and the materials have been investigated for their ability to act as controlled release vehicles in ophthalmic drug delivery. Studies on the effects of network structure upon swelling properties, adhesiveness to substrates that mimic mucosal surfaces and biodegradability, coupled with in vitro drug release investigations employing ophthalmic drugs with differing aqueous solubilities, have identified nanoparticle compositions for each of the candidate drug molecules. The hybrid nanoparticles combine the temperature sensitivity of N-isopropylacrylamide or the good swelling characteristics of 2-hydroxyethyl methacrylate with the susceptibility of chitosan to lysozyme-induced biodegradation. PMID:19433871

  19. Dynamics of the layer-by-layer assembly of a poly(acrylic acid)-lanthanide complex colloid and poly(diallyldimethyl ammonium).

    Science.gov (United States)

    Xu, Jiali; Wang, Zhiliang; Wen, Lingang; Zhou, Xianju; Xu, Jian; Yang, Shuguang

    2016-01-21

    Poly(acrylic acid) (PAA) and lanthanide (Ln) ions, such as Ce(3+), Eu(3+), and Tb(3+), were prepared as dispersed complex colloidal particles through three different protocols with rigorous control of the pH value and mixing ratio. The negatively charged PAA-Ln complex particles were layer-by-layer (LbL) assembled with positively charged poly(diallyldimethyl ammonium) (PDDA) to prepare a thin film. The film thickness growth is much quicker than PDDA/PAA film. Due to the incorporation of Ln(3+) ions, the film exhibits fluorescence. During LbL assembly, PDDA-PAA association based on electrostatic force and PAA-Ce association based on coordination are in competition, which leads to the LbL assembly of PDDA and PAA-Ln complex colloidal particles being a complicated dynamic process. PMID:26549538

  20. Preparation and characterization of electrically conductive composites of poly(vinyl alcohol–g–poly(acrylic acid hydrogels impregnated with polyaniline (PANI

    Directory of Open Access Journals (Sweden)

    2008-01-01

    Full Text Available Novel electrically conducting composite materials consisting of poly(aniline (PANI nanoparticles dispersed in a poly(vinyl alcohol (PVA-g-poly(acrylic acid (PAA hydrogels were prepared within the polymer matrix by in situ polymerization of aniline. The conversion yield of aniline into PANI particles was determined gravimetrically while structural confirmation of the synthesized polymer was sought by Fourier Transform Infrared (FTIR, UV-visible analysis and X-ray diffraction (XRD technique. Morphology and dimension of PANI particles embedded into the colored optically semi-transparent hydrogels were evaluated by Scanning Electron Microscopy (SEM analysis. Electrical conductivity of composite hydrogels of different composition was determined by LCR meter while electroactive behavior of composite hydrogels swollen in electrolyte solution was investigated by Effective Bend Angle (EBA measurements.

  1. Reusable nanocomposite of CoFe2O4/chitosan-graft-poly(acrylic acid) for removal of Ni(II) from aqueous solution

    International Nuclear Information System (INIS)

    In this paper, CoFe2O4/chitosan-graft-poly(acrylic acid) (CoFe2O4/CS-graft-PAA) nanocomposites were prepared successfully by coprecipitation of the compounds in alkaline solution and were used for removal of nickel (II) ions from aqueous solution. The sorption rate was affected significantly by the initial concentration of the solution, sorbent amount, and pH value of the solution. Batch experiments were conducted to investigate the adsorption capacity under different initial concentration (ranging from 25 to 150 mg L−1), solution pH (4.1, 5.3, 6.4 and 7.6), and contact time. These nanocomposites can be recycled conveniently from water with the assistance of an external magnet because of their exceptional properties. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), x-ray powder diffraction (XRD), and thermogravimetric analysis (TGA). (papers)

  2. High cycling stability of anodes for lithium-ion batteries based on Fe3O4 nanoparticles and poly(acrylic acid) binder

    Science.gov (United States)

    Maroni, F.; Gabrielli, S.; Palmieri, A.; Marcantoni, E.; Croce, F.; Nobili, F.

    2016-11-01

    Fe3O4 nanoparticles synthesized by a base catalyzed method are tested as anode material for Li-ion batteries. The pristine nanoparticles are morphologically characterized showing an average size of 11 nm. Electrodes are prepared using high-molecular weight Poly (acrylic acid) as improved binder and ethanol as low cost and environmentally friendly solvent. The evaluation of electrochemical properties shows high specific capacity values of 857 mA hg-1 after 200 cycles at a specific current of 462 mAg-1, as well as an excellent rate capability with specific current values up to 18480 mAg-1. To the best of our knowledge, this is the first report of Fe3O4 nanoparticles cycling with PAA as binder.

  3. Electrospun Poly(acrylonitrile-co-acrylic acid) Nanofibrous Membranes for Catalase Immobilization:Effect of Porphyrin Filling on the Enzyme Activity

    Institute of Scientific and Technical Information of China (English)

    KE Bei-bei; WAN Ling-shu; HUANG Xiao-jun; XU Zhi-kang

    2011-01-01

    Porphyrin-filled nanofibrous membranes were facilely prepared by electrospinning of the mixtures of poly(acryionitrile-co-acrylic acid)(PANCAA) and porphyrins. 5,10,15,20-Tetraphenyiporphyrin(TPP) and its metalloderivatives(ZnTPP and CuTPP) were studied as filling mediators for the immobilization of redox enzyme. Results indicate that the introduction of TPP, ZnTPP and CuTPP improves the retention activity of the immobilized catalase.Among these three porphyrins, the ZnTPP-filled PANCAA nanofibrous membrane exhibits an activity retention of 93%, which is an exciting improvement. This improvement is attributed to both the strong catalase-porphyrin affinity and the possible facilitated electron transfer induced by the porphyrin as evidenced by quartz crystal microbalance (QCM) and fluorescence spectroscopy studies.

  4. 金属离子改性NaY分子筛催化乳酸脱水制丙烯酸%Catalytic Dehydration of Lactic Acid to Acrylic Acid over NaY Zeolites Modified with Metallic Ions

    Institute of Scientific and Technical Information of China (English)

    闫婕; 余定华; 孙鹏; 黄和

    2011-01-01

    对乳酸脱水制取丙烯酸的热力学进行了计算,并以NaY分子筛为催化剂对乳酸脱水反应参数进行了优化;采用K+,Ba2+,La3+对NaY分子筛进行改性,并用N2物理吸附,NH3 - TPD,CO2 - TPD等手段对催化剂进行了表征.实验结果表明,优化的工艺条件为乳酸质量分数38%、载气N2流量30 mL/min;金属离子改性的分子筛改变了分子筛表面酸碱位点分布进而影响了催化剂的乳酸脱水性能,其中,La/NaY分子筛具有适度的酸量及最高的碱量从而呈现出优异的催化件能,在325℃时丙烯酸收率达56.3%,而NaY分子筛上丙烯酸收率只有21.6%.适当降低酸强度及酸量可提高丙烯酸收率,并可削弱乙醛的形成;而提高碱量及适度减弱碱强度可有效提高丙烯酸收率.%The catalytic dehydration of bio-based lactic acid to acrylic acid over the unmodified and the modified NaY zeolite catalysts with K+ , Ba2+ and La3+ was investigated and the thermodynamic analysis for the dehydration reaction was performed. The effects of the input concentration of lactic acid and the flow rate of nitrogen on the dehydration were studied. To improve the catalytic performance of the NaY catalyst, the NaY zeolite catalysts modified with K+, Ba2+ and La3+ were prepared and characterized by means of N2 adsorption, NH3-TPD and CO2-TPD. The results showed that the optimized concentration of lactic acid and the flow rate of nitrogen were 38% (w) and 30 mL/ min, respectively. The modification could change the surface acid/base distributions and affect the catalytic performance. La/NaY exhibited the highest acrylic acid yield 56.3 % at 325 t, which could be attributed to the appropriate acidic amount and high basic amount on the catalyst, while NaY only indicated 21.6% acrylic acid yield under the same conditions. The research showed that the suitable declines of both acidic sites and acid strength of the catalysts were beneficial to the formation of acrylic acid

  5. Structural changes of polyacids initiated by their neutralization with various alkali metal hydroxides. Diffusion studies in poly(acrylic acid)s.

    Science.gov (United States)

    Masiak, Michal; Hyk, Wojciech; Stojek, Zbigniew; Ciszkowska, Malgorzata

    2007-09-27

    The changes in the three-dimensional structure of the poly(acrylic acid), PAA, induced by incorporation of various alkali-metal counterions have been evaluated by studying diffusion of an uncharged probe (1,1'-ferrocenedimethanol) in the polymeric media. The studies are supported by the measurements of conductivity and viscosity of the polymeric media. Solutions of linear PAA of four different sizes (molecular weights: 450,000, 750,000, 1,250,000, 4,000,000) were neutralized with hydroxides of alkali metals of group 1 of the periodic table (Li, Na, K, Rb, Cs) to the desired neutralization degree. The transport properties of the obtained polyacrylates were monitored by measuring the changes in the probe diffusion coefficient during the titration of the polyacids. The probe diffusivity was determined from the steady-state current of the probe voltammetric oxidation at disk microelectrodes. Diffusivity of the probe increases with the increase in the degree of neutralization and with the increase in viscosity. It reaches the maximum value at about 60-80% of the polyacid neutralization. The way the probe diffusion coefficients change is similar in all polyacid solutions and gels. The increase in the size of a metal cation causes, in general, an enhancement in the transport of probe molecules. The biggest differences in the probe diffusivities are between lithium and cesium polyacrylates. The differences between the results obtained for cesium and rubidium are not statistically significant due to lack of good precision of the voltammetric measurements. The measurements of the electric conductivity of polyacrylates and the theoretical predictions supplemented the picture of electrostatic interactions between the polyanionic chains and the metal cations of increasing size. In all instances of the PAAs, the viscosity of the solutions rapidly increases in the 0-60% range of neutralization and then becomes constant in the 60-100% region. With the exception of the shortest

  6. Preparation of grafted polymer from sugarcane bagasse fiber and acrylic acid%蔗渣纤维丙烯酸高吸水树脂的制备

    Institute of Scientific and Technical Information of China (English)

    谢娜纯; 王江; 曹阳

    2012-01-01

    Superabsorbent polymer of sugarcanr bagasse fiber has been obtained by graft copolymerization of acrylic acid (AA) monomer using potassium persulfate (PP) as initiator in an aqueous medium. Crafting parameters were evaluated at different content of monomer, initiator, cross linker and neutralization. And the result had shown that the optimum condition for graft copolymerization is 10%, 2%, 0.1%, 80% for the content of AA, PP, cross linker and neutralization, respectively. On the basis of Fourier transform infrared speclroscopy for the graft copolymer, the reaction steps for graft copolymerization have been proposed. The maximum absorption capacity of the copolymer for distilled water is 765.7g"g~'.%以蔗渣纤维为原料.丙烯酸为接枝单体,N,N-亚甲基双丙烯酰胺为交联剂,K2S2O8为引发剂,通过溶液聚合的方法合成了蔗渣纤维(sugarcane bagasse,SCB)与聚丙烯酸(poly acrylic acid,PAA)的接枝共聚高吸水树脂( SCB-g-PAA).研究了丙烯酸用量、引发剂用量、交联剂用量以及中和度对吸水树脂吸水倍率的影响,结果表明,该接枝共聚吸水树脂的最佳合成条件是以丙烯酸用量为标准,蔗渣纤维、K2S2O8、交联剂用量分别是10%、2%、0.1%,中和度为80%,共聚物吸水倍率最高为765.7g·g-1.

  7. Study on the Super Absorbent Polymer Based on Acrylic Acid%高吸水性丙烯酸树脂的制备及性能研究

    Institute of Scientific and Technical Information of China (English)

    殷榕灿; 陶栋梁

    2014-01-01

    The Super Absorbent Polymer ( SAP) was prepared by solution polymerization in which acrylic acid was used as monomer , potassium persulfate ( KPS ) was used as initiator and N , N'-methylene bisacrylamide as cross -linking agent.The influencing factors of the water absorption capacities such as the amount of cross -linking agent , initiation, neutralization degree of acrylic acid and monomer concentration were characterized.The best absorbability of was the SAP 1 132 g/g in deionized water and 105 g/g in the 0.9%NaCl solution.%采用丙烯酸为单体,以过硫酸钾为引发剂, N,N′-亚甲基双丙烯酰胺为交联剂,通过水溶液聚合法制备高吸水性树脂。分别讨论了交联剂、引发剂、中和度、单体浓度对吸水(盐)率的影响,用红外光谱表征了样品,确定了最佳方案。结果表明: N,N'-亚甲基双丙烯酰胺和K2 S2 O4用量分别为AA的0.04%和4%,产品在去离子水及0.9%NaCl中的吸水倍率分别可达到1132倍和105倍。

  8. One-step routes from di- and triblock copolymer precursors to hydrophilic nanoporous poly(acrylic acid)-b-polystyrene

    DEFF Research Database (Denmark)

    Guo, Fengxiao; Jankova Atanasova, Katja; Schulte, Lars;

    2008-01-01

    Nanoporous polystyrene with hydrophilic pores was prepared from di- and triblock copolymer precursors. The precursor material was either a poly(tert-butyl acryl ate)-b-polystyrene (PtBA-b-PS) diblock copolymer synthesized by atom transfer radical polymerization (ATRP) or a polydimethylsiloxane...... that TFA can remove PDMS is important, not least as an alternative to the more hazardous HE The investigated di- and triblock copolymer samples were of either hexagonal or lamellar morphology. The resulting nanoporous polymers were characterized by infrared spectroscopy, small-angle X-ray scattering......, and scanning electron microscopy. In contact with water, all the prepared nanoporous polymers showed spontaneous water uptake close to the amounts expected from the precursor block copolymer compositions....

  9. Mesoporous silica nanoparticles with bilayer coating of poly(acrylic acid-co-itaconic acid) and human serum albumin (HSA): A pH-sensitive carrier for gemcitabine delivery.

    Science.gov (United States)

    Pourjavadi, Ali; Tehrani, Zahra Mazaheri

    2016-04-01

    Novel bilayer coated mesoporous silica nanoparticle (MCM-41) based on pH sensitive poly(acrylic acid-co-itaconic acid) and human serum albumin (HSA) was designed for controlled delivery of gemcitabine (anticancer drug) to cancer cells. The shell around the mesoporous silica has bilayer structure. Poly(acrylic acid-co-itaconic acid) was used as pH-sensitive inner shell and human serum albumin, HSA, was used as outer shell. The core-shell structure was formed due to electrostatic interaction between ammonium groups of modified MCM-41 and carboxylate groups of copolymer. Also, the albumin layer was wrapped around the copolymer coated nanoparticle by electrostatic interaction between ammonium groups from protein and carboxylate ions of copolymer shell. Moreover, the maximum release occurred at pH 5.5 (pH of endosomes) because the bilayer shell collapsed at this pH. The drug nanocarrier would be a good candidate for tumor therapy due to its biocompatibility, controlled release and pH responsive behavior. PMID:26838909

  10. Study on acrylic acid bentonite of high amount/poly(sodium acrylate) superabsorbent composite Ⅰ :the preparation process and morphology%高含量丙烯酸膨润土/聚丙烯酸钠高吸水性复合材料的研究Ⅰ:制备工艺与形貌

    Institute of Scientific and Technical Information of China (English)

    付丽华; 彭英知; 韦藤幼; 童张法

    2012-01-01

    Superabsorbent composite of high amount of acrylic acid bentonite/poly(sodium acrylic) was synthesized through solution polymerization with acrylic acid bentonite(ABT) and sodium acrylic and acrylic acid. The morphology of the composite was observed by scanning electron microscope(SEM). The results show that a-crylic acid bentonite is evenly and disorder dispersed in the composite with the sheets of 20-30 nm thickness. The preparation process are optimized. The results are as follows. The amount of ABT, crosslinker and initiator are 30wt% , 0. 3wt% , 1. lwt% of the monomer mass respectively. The total water in the system is 340 % of the monomer mass, the neutralization degree is 64 %). The absorbency of the composite is 1103 g/g in deionized water in the conditions. At the same time, the water retention property of the superabsorbent composite(PAA) is better compared to that of PAA.%通过特殊工艺将丙烯酸膨润土(简称ABT)和丙烯酸钠单体采用溶液聚合法制备出高含量丙烯酸膨润土/聚丙烯酸钠高吸水性复合材料(简称HABT/PAA).SEM考察材料的形貌得知,ABT以20~30nm的尺寸较均匀、无序地分散在聚合物基体中,且与聚合物有很好的相容性.对合成工艺进行了优化得到较优的工艺:ABT用量为单体质量的30%(质量分数),交联剂用量为单体质量的0.3%(质量分数),引发剂用量为单体质量的1.1%(质量分数),体系总水量为单体质量的340%(质量分数),中和度为64%,在此条件下,材料吸附去离子水的能力为1103g/g.同时,HABT/PAA的保水性能较聚丙烯酸钠(PAA)好.

  11. INFLUENCE OF ZnSt2 ON STRUCTURE OF ACRYLATE-BASED IONOMERS WITH DIFFERENT LANTHANIDE (La(lll)) ION AND ACID CONTENTS

    Institute of Scientific and Technical Information of China (English)

    Xiao-nan Zhu; Yi-hu Song; Qiang Zheng

    2012-01-01

    A series of acrylate processing aid (ACR)-based ionomers with different lanthanide (La(Ⅲ)) ion and acid contents were synthesized,and the interaction between ionomer and zinc stearate (ZnSt2) was investigated immediately after thermally annealing the ionomer/ZnSt2 (3/1 in weight) mixtures at 180℃.The results revealed that the ion groups in ionomer have a strong interaction with ZnSt2.The annealed mixtures contained hot alcohol extractable and unextractable ZnSt2.The melting of ZnSt2 and the thermal behavior of the ionomer in the annealed mixtures were seriously influenced by the contents of La(Ⅲ) and acid in the ionomers.The ionomer containing 0.25 mmol/g acid and 0.37 mmol/g La(Ⅲ) has a detectable cluster phase.Annealing its ZnSt2 mixture could break down the cluster phase and lower glass transition temperature of the ionomer matrix.However,washing away the extractable ZnSt2 led to the reappearance of the cluster transition temperature and return of the glass transition temperature of matrix to the original position.

  12. Synthesis, Structures and Properties of Three Metal-organic Frameworks Based on 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Peng; Ren, Tiantian; Tian, Weiman; Xu, Wenjia; Pan, Ganghong; Yin, Xianhong [Guangxi Univ. for Nationalities, Nanning (China)

    2014-01-15

    Three new transition metal complexes based on Ozagrel [Cu(Ozagrel)]{sub n} (1), [Zn(Ozagrel)(Cl)]{sub n} (2), [Mn{sub 2}-(Ozagrel)(1,4-ndc){sub 2}]·(H{sub 2}O){sub n} (3), (Ozagrel = 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic acid; 1,4-ndc = 1,4-Naphthalenedicarboxylic acid) have been hydrothermally synthesized and characterized by elemental analyse, IR, TG, PXRD, electrochemical analysis and single crystal X-ray diffraction. X-ray structure analysis reveals that 1 and 3 are 3D coordination polymers, while complex 2 is a two-dimensional network polymer, the 2D layers are further packed into 3D supramolecular architectures that are connected through hydrogen bonds. The electrochemistry of 1-3 was studied by cyclic voltammetry in methanol and water using a glassy carbon working electrode. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated.

  13. Characterization of electron beam cured epoxy acrylate

    International Nuclear Information System (INIS)

    Epoxy resin has wide application in various industrial fields because of their good mechanical strength, superiority adhesion and low shrinkage etc. And the typical curing method for epoxy resins is thermal and press compaction. However, a curing method was used electron beam process in this study. Epoxy acrylate was fabricated from mixture of epoxy, acrylic acid, tetraphenylporphyrin (TPP) and hydroquinone monomethyl ether (MEHQ) with mole ratios. Then electron beam irradiation effect on the curing of the epoxy acrylate resin was investigated various absorption dose in nitrogen atmospheres at room temperature. The dynamic mechanical and thermal properties of the irradiated epoxy acrylate resins were characterized using dynamic mechanical analysis (DMA) and thermogravimetric analyzer (TGA). And the tensile and flexural strength were measured by an universal tensile machine (UTM)

  14. STUDY ON REGULARITIES OF GRAFT COPOLYMERIZATION OF ACRYLIC ACID ONTO FUNGAL CELL WALL%米根霉细胞壁结构性多糖与丙烯酸接枝共聚反应研究

    Institute of Scientific and Technical Information of China (English)

    张诚; 孟琴; 吕德伟

    2001-01-01

    For the aim of getting macromolecular flocculant,we studied the copolymerization of acrylic acid onto Rhi.oryzae cell wall structural polysaccharide by the initiation of ceric ammonium nitrate.The effect of concentration of initiator and monomer,reaction temperature and reaction time on grafting percentage was investigated.To Rhi.oryzae cell wall structural polysaccharide the maximal grafting percentage of 135.5% was achieved at [Ce+4]=5mmol/L,[AA]=1mol/L,T=60℃,t=3h.Then choosing organic dyes as the flocculated substances,by comparing with the chitosan,polyacrylamide and Rhi.oryzae cell wall structural polysaccharide before grafting,we studied the flocculent capability of Rhi.oryzae cell wall structural polysaccharide after grafting acrylic acid.The grafting product had excellent flocculent effect on basic and neutral dyes.

  15. Multimodal particle size distribution or fractal surface of acrylic acid copolymer nanoparticles: A small-angle X-ray scattering study using direct Fourier and indirect maximum entropy methods

    OpenAIRE

    Mueller, J.J.; Hansen, S; Lukowski, G.; Gast, K.

    1995-01-01

    Acrylic acid copolymers are potential carriers for drug delivery. The surface, surface rugosity and the absolute dimension of the particles are parameters that determine the binding of drugs or detergents, diffusion phenomena at the surface and the distribution of the carrier within the human body. The particle-size distribution and surface rugosity of the particles have been investigated by small-angle X-ray scattering and dynamic light scattering. Direct Fourier transform as well as a new s...

  16. Obtention and characterization of acrylic acid-i-polyethylene organometallic copolymers with Mo, Fe, Co, Zn, and Ni; Obtencion y caracterizacion de copolimeros organometalicos de acido acrilico-i-polietileno, con Mo, Fe, Co, Zn y Ni

    Energy Technology Data Exchange (ETDEWEB)

    Dorantes, G.; Urena, F.; Lopez, R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Lopez, R. [Universidad Autonoma del Estado de Mexico (Mexico)

    1997-07-01

    In this study a graft acrylic acid (AA) in low density polyethylene (PEBD) copolymers were prepared, using as reaction initiator, gamma radiation at different doses. These copolymers were coordinated with molybdenum, cobalt, iron, zinc and nickel. the obtained polymeric materials were characterized by conventional analysis techniques. It was studied the measurement parameter variation of the positron annihilation when they inter activated with this type of materials and so obtaining information about microstructure of these polymers. (Author)

  17. 聚丙烯酸-腐植酸钠复合高吸水树脂的合成研究∗%Study on the Synthesis of Poly Acrylic Acid-sodium Humate Composite Super Absorbent Polymer

    Institute of Scientific and Technical Information of China (English)

    李东芳; 杜明华

    2015-01-01

    该研究采用不除去丙烯酸中阻聚剂及不通氮气的工艺,以丙烯酸、腐植酸钠为原料,通过水溶液聚合法制备了聚丙烯酸-腐植酸钠复合高吸水树脂。研究结果表明:该复合高吸水树脂在丙烯酸的中和度为60%,腐植酸钠用量为1.0g,引发剂过硫酸钾用量为55mg,交联剂N,N′-亚甲基双丙烯酰胺用量为20mg时,吸蒸馏水量最大,为1200 g/g。%The poly acrylic acid-sodium humate composite super absorbent polymer was synthesized by aqueous solution polymerization through the technology of no nitrogen and not removing polymerization inhibitor in acrylic acid. In the synthesis process, acrylic acid and sodium humate were as monomer. The study results showed that when the neutralization degree of acrylic acid was 60%,the dosage of sodium humate was 1. 0g,the dosage of initia-tor( potassium persulfate) was 55mg, and the dosage of crosslinking agent ( N, N′-methylenebisacrylamide) was 20mg,the highest distilled water-absorbing capacity of the composite super absorbent polymer was 1200g/g.

  18. 聚丙烯酸-腐植酸钠复合高吸水树脂的合成研究∗%Study on the Synthesis of Poly Acrylic Acid-sodium Humate Composite Super Absorbent Polymer

    Institute of Scientific and Technical Information of China (English)

    李东芳; 杜明华

    2015-01-01

    The poly acrylic acid-sodium humate composite super absorbent polymer was synthesized by aqueous solution polymerization through the technology of no nitrogen and not removing polymerization inhibitor in acrylic acid. In the synthesis process, acrylic acid and sodium humate were as monomer. The study results showed that when the neutralization degree of acrylic acid was 60%,the dosage of sodium humate was 1. 0g,the dosage of initia-tor( potassium persulfate) was 55mg, and the dosage of crosslinking agent ( N, N′-methylenebisacrylamide) was 20mg,the highest distilled water-absorbing capacity of the composite super absorbent polymer was 1200g/g.%该研究采用不除去丙烯酸中阻聚剂及不通氮气的工艺,以丙烯酸、腐植酸钠为原料,通过水溶液聚合法制备了聚丙烯酸-腐植酸钠复合高吸水树脂。研究结果表明:该复合高吸水树脂在丙烯酸的中和度为60%,腐植酸钠用量为1.0g,引发剂过硫酸钾用量为55mg,交联剂N,N′-亚甲基双丙烯酰胺用量为20mg时,吸蒸馏水量最大,为1200 g/g。

  19. Poly-N-Isopropylacrylamide/acrylic Acid Copolymers for the Generation of Nanostructures at Mica Surfaces and as Hydrophobic Host Systems for the Porin MspA from Mycobacterium smegmatis

    OpenAIRE

    Gamage, Pubudu; Basel, Matthew T.; Lovell, Kimberly; Pokhrel, Megh Raj; Battle, Deletria; Ito, Takashi; Pavlenok, Mikhail; Niederweis, Michael; Stefan H. Bossmann

    2009-01-01

    The work presented here aims at utilizing poly-N-isopropyl-acrylamide/acrylic acid copolymers to create nanostructured layers on mica surfaces by a simple spin-casting procedure. The average composition of the copolymers determined by elemental analysis correlates excellently with the feed composition indicating that the radical polymerization process is statistical. The resulting surfaces were characterized by Atomic Force Microscopy (magnetic AC-mode) at the copolymer/air interface. Postpol...

  20. 麦秸秆纤维素接枝丙烯酸制备高吸水性树脂的研究%Preparation of Super Absorbent Res in by Graft Copolymerization of Wheat Straw Cellulose and Acrylic Acid

    Institute of Scientific and Technical Information of China (English)

    贺龙强; 刘中阳

    2011-01-01

    With acrylic acid as modifier monomer, N,N'-methylene-bis-acrylamide as crosslinker,and Potassium persulfate as initiator,super absorbent resin was synthesized by grafting copolymerization of the acrylic acid and cellulose from wheat straw after pretreatment. The effects of initiator does, cross linker dosage, monomer dose, and neutralization of acrylic acid on water absorption of resin were studied. The water absorben-cy of resin obtained under the optimal synthetic conditions was both large and rapid.%以小麦秸秆为原料,经预处理得纤维素后,以N,N’-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用水溶液聚合法制备了纤维素接枝丙烯酸的高吸水性树脂,探讨了引发剂用量、交联剂用量、单体丙烯酸用量、丙烯酸中和度等因素对吸水率的影响.最佳条件下制得的树脂不仅吸水量大,而且还具有吸水速率快的特性.

  1. Poly (N-vinyl-2-pyrrolidone-co-acrylic acid): Comparing of Traditional Heating and Microwave-Assisted Free Radical Polymerization

    International Nuclear Information System (INIS)

    In organic chemistry microwave irradiation has become a common heat source and the use of microwave irradiation is also increasingly studied for polymerization reactions. Polymers have been synthesized at long reaction times by classical thermal methods. In contrast, microwave-assisted polymer synthesis is a well-known and most useful method, which is requiring shorter reaction times. In this study, our aims are to compare THPS and MAPS methods between themselves, and investigate the effect of temperature in MAPS method at different parameters such as reaction times, weight average molecular weight (Mw), polydispersity index (PDI), hydrodynamic radius (Rh), intrinsic and Mark Houwink equation constant (a) of copolymers, viscosity Firstly we synthesized N-vinyl-2-pyrrolidone-acrylic acid copolymers (P(VP-co-AA)) both with traditional heating polymer synthesis (THPS) and microwave-assisted polymer synthesis (MAPS) method comparatively in this study. Secondly, to research temperature effect on MAPS method in addition to microwave irradiation power, polymer synthesis at 40 degree C, 50 degree C and 80 degree C were tried. For analyzing of copolymers Fourier Transform Infrared (FT-IR) spectroscopy and Gel Permeation Chromatography (GPC) system with four detectors were used. (author)

  2. Photocurable bioactive bone cement based on hydroxyethyl methacrylate-poly(acrylic/maleic) acid resin and mesoporous sol gel-derived bioactive glass.

    Science.gov (United States)

    Hesaraki, S

    2016-06-01

    This paper reports on strong and bioactive bone cement based on ternary bioactive SiO2-CaO-P2O5 glass particles and a photocurable resin comprising hydroxyethyl methacrylate (HEMA) and poly(acrylic/maleic) acid. The as-cured composite represented a compressive strength of about 95 MPa but it weakened during soaking in simulated body fluid, SBF, qua its compressive strength reached to about 20 MPa after immersing for 30 days. Biodegradability of the composite was confirmed by reducing its initial weight (~32%) as well as decreasing the molecular weight of early cured resin during the soaking procedure. The composite exhibited in vitro calcium phosphate precipitation in the form of nanosized carbonated hydroxyapatite, which indicates its bone bonding ability. Proliferation of calvarium-derived newborn rat osteoblasts seeded on top of the composite was observed during incubation at 37 °C, meanwhile, an adequate cell supporting ability was found. Consequently, it seems that the produced composite is an appropriate alternative for bone defect injuries, because of its good cell responses, high compressive strength and ongoing biodegradability, though more in vivo experiments are essential to confirm this assumption. PMID:27040248

  3. Measurement of non-DLVO force on a silicon substrate coated with ammonium poly(acrylic acid) using scanning probe microscopy

    Science.gov (United States)

    Isobe, Toshihiro; Nakano, Yosuke; Kameshima, Yoshikazu; Nakajima, Akira; Okada, Kiyoshi

    2009-07-01

    The repulsive force originating from steric hindrance of polymers in aqueous solvent was investigated using scanning probe microscopy (SPM). The contact angle (CA) of ammonium poly(acrylic acid) (PAA) solution on the Si surface was measured to estimate the state of the Si substrate. Results of CA measurement show that the Si surface was fully covered with PAA at 0.1 mass% in aqueous solution. The interaction force between the Si tip and the wafer was estimated using the SPM force curve mode. The force curve measured in the ion-exchanged purified water showed the typical relation predicted by Derjaguin-Landau-Verway-Overbeek (DLVO) theory. However, the force curve shape in the 0.1 mass% PAA solution was significantly different. Only a repulsive force was observed at less than about 4 nm of separation distance between the Si wafer and cantilever tip. This distance originated from the steric repulsions of PAA adsorbed onto the Si wafer and cantilever tip.

  4. Poly(acrylic acid) Bridged Gadolinium Metal-Organic Framework-Gold Nanoparticle Composites as Contrast Agents for Computed Tomography and Magnetic Resonance Bimodal Imaging.

    Science.gov (United States)

    Tian, Chixia; Zhu, Liping; Lin, Feng; Boyes, Stephen G

    2015-08-19

    Imaging contrast agents for magnetic resonance imaging (MRI) and computed tomography (CT) have received significant attention in the development of techniques for early stage cancer diagnosis. Gadolinium (Gd)(III), which has seven unpaired electrons and a large magnetic moment, can dramatically influence the water proton relaxation and hence exhibits excellent MRI contrast. On the other hand, gold (Au), which has a high atomic number and high X-ray attenuation coefficient, is an ideal contrast agent candidate for X-ray-based CT imaging. Gd metal-organic framework (MOF) nanoparticles with tunable size, high Gd(III) loading and multivalency can potentially overcome the limitations of clinically utilized Gd chelate contrast agents. In this work, we report for the first time the integration of GdMOF nanoparticles with gold nanoparticles (AuNPs) for the preparation of a MRI/CT bimodal imaging agent. Highly stable hybrid GdMOF/AuNPs composites have been prepared by using poly(acrylic acid) as a bridge between the GdMOF nanoparticles and AuNPs. The hybrid nanocomposites were then evaluated in MRI and CT imaging. The results revealed high longitudinal relaxivity in MRI and excellent CT imaging performance. Therefore, these GdMOF/AuNPs hybrid nanocomposites potentially provide a new platform for the development of multimodal imaging probes.

  5. Preparation of superabsorbent by graft copolymerization of acrylic acid onto corn starch using K2S2O8 and rare earths as initiators

    Institute of Scientific and Technical Information of China (English)

    BAI Yong-ping; LI Wei-dong; FENG Li-qun; ZHAO chao

    2008-01-01

    K2S2O8 and rare earths (RE) were used as initiators to prepare superabsorbents by graft copolymeri-zation of acrylic acid (AA) onto corn starch. The effects of monomer concentration, initiator K2S2O8 concentra-tion, cross-linker concentration, reaction temperature and the concentration ratio of RE and K2S2O8 on the graft copolymerization were studied in terms of the water absorption capacity of superabsorbents. Results indicate that the optimum conditions obtained for the grafting of AA onto 5g starch are as follows: AA of 75. 773 g/L, K2S2O8 of 0.437 g/L, RE of 0.874 g/L, cross-linker of 0.381 g/L and temperature of 70℃. The maximum water absorption capacity obtained is 740 g/g. The new method of graft polymerization is easily proceeded and controlled. The graft copolymers were characterized by infra-red spectroscopy, scanning electron microscopy and TG. Results characterized by IR and SEM give strong evidence for grafting of AA onto corn starch, and those characterized by TG reveal that the grafting of AA improves the thermostability of corn starch.

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

    Science.gov (United States)

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

    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 3months 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. PMID:27157754

  7. Radiation grafting of pH-sensitive acrylic acid and 4-vinyl pyridine onto nylon-6 using one- and two-step methods

    Science.gov (United States)

    Ortega, Alejandra; Alarcón, Darío; Muñoz-Muñoz, Franklin; Garzón-Fontecha, Angélica; Burillo, Guillermina

    2015-04-01

    Acrylic acid (AAc) and 4-vinyl pyridine (4VP) were γ-ray grafted onto nylon-6 (Ny6) films via pre-irradiation oxidative method. These monomers were grafted using a one-step method to render Ny6-g-(AAc/4VP). A two-step or sequential method was used to render (Ny6-g-AAc)-g-4VP. Random copolymer branches were obtained when the grafting was carried out via one-step method using the two monomers together. The two-step method was applied to graft chains of 4VP on both Ny6 substrate and previously grafted AAc chains (Ny6-g-AAc). The two types of binary copolymers synthesized were characterized to determine the amount of grafted polymers, the thermal behavior (DSC and TGA), the surface composition (XPS), and the pH responsiveness. In the two-step process, it is possible to achieve a higher graft yield, better control of the amount of each monomer, good reversibility in the swelling/deswelling process and shorter time to achieve equilibrium swelling.

  8. "Stable-on-the-Table" Biosensors: Hemoglobin-Poly (Acrylic Acid) Nanogel BioElectrodes with High Thermal Stability and Enhanced Electroactivity.

    Science.gov (United States)

    Ghimire, Ananta; Zore, Omkar V; Thilakarathne, Vindya K; Briand, Victoria A; Lenehan, Patrick J; Lei, Yu; Kasi, Rajeswari M; Kumar, Challa V

    2015-01-01

    In our efforts toward producing environmentally responsible but highly stable bioelectrodes with high electroactivities, we report here a simple, inexpensive, autoclavable high sensitivity biosensor based on enzyme-polymer nanogels. Met-hemoglobin (Hb) is stabilized by wrapping it in high molecular weight poly(acrylic acid) (PAA, M(W) 450k), and the resulting nanogels abbreviated as Hb-PAA-450k, withstood exposure to high temperatures for extended periods under steam sterilization conditions (122 °C, 10 min, 17-20 psi) without loss of Hb structure or its peroxidase-like activities. The bioelectrodes prepared by coating Hb-PAA-450k nanogels on glassy carbon showed well-defined quasi-reversible redox peaks at -0.279 and -0.334 V in cyclic voltammetry (CV) and retained >95% electroactivity after storing for 14 days at room temperature. Similarly, the bioelectrode showed ~90% retention in electrochemical properties after autoclaving under steam sterilization conditions. The ultra stable bioelectrode was used to detect hydrogen peroxide and demonstrated an excellent detection limit of 0.5 μM, the best among the Hb-based electrochemical biosensors. This is the first electrochemical demonstration of steam-sterilizable, storable, modular bioelectrode that undergoes reversible-thermal denaturation and retains electroactivity for protein based electrochemical applications. PMID:26393601

  9. Silicone/Acrylate Copolymers

    Science.gov (United States)

    Dennis, W. E.

    1982-01-01

    Two-step process forms silicone/acrylate copolymers. Resulting acrylate functional fluid is reacted with other ingredients to produce copolymer. Films of polymer were formed by simply pouring or spraying mixture and allowing solvent to evaporate. Films showed good weatherability. Durable, clear polymer films protect photovoltaic cells.

  10. Palm oil based polyols for acrylated polyurethane production

    International Nuclear Information System (INIS)

    Palm oil becomes important renewable resources for the production of polyols for the polyurethane manufacturing industry. The main raw materials used for the production of acrylated polyurethane are polyols, isocyanates and hydroxyl terminated acrylate compounds. In these studies, polyurethane based natural polymer (palm oil), i.e., POBUA (Palm Oil Based Urethane Acrylate) were prepared from three different types of palm oil based polyols i.e., epoxidised palm oil (EPOP), palm oil oleic acid and refined, bleached and deodorized (RBD) palm olein based polyols. The performances of these three acrylated polyurethanes when used for coatings and adhesives were determined and compared with each other. (Author)

  11. Radiation induced copolymerization of binary monomers system(styrene/acrylic acid) and its application in removal of some heavy metals and dyes from aquatic solutions

    International Nuclear Information System (INIS)

    Radiation-induced coploymerization of binary monomer system styrene/acrylic acid (Sty/AAc) using direct radiation technique has been investigated. The appropriate reaction conditions such as solvent, commonomer concentration, commonomer composition and irradiation dose at which the coplymerization process was carried out successfully were selected. The effect of different parameters on the conversion percent of the commonmer into coplomer was studied by gravimetric method. It was found that, using methanol/distilled water as a cosolvent with composition 80/20 wt% enhanced the copolymerization process. The conversion (%) of the commonomer was increased with increasing radiation dose. Some properties of the coplymer such as wate uptake, thermal stability, surface topography were investigated. The improvement in such properties of the prepared coplymers was observed which makes possible uses in some practical applications such as in the removal of some heavy metals and dyes from wastewater. the prepared copolymer has good chemical and thermal stability where as the styrene content lead to increase the swelling behaviour. It was found that the maximum metal uptake by the coplymer is ordered in the sequence of Bp2+>Cu2+>Ni2+. The possibility of the removal of three classes of dyes from aqueous solutions; namely wegocet yellow 4GL (direct yellow 44), congo red (diect red 28). Remacryl blue 3G (basic blue3) and xylene blue *acid blue 7 was studied. It could be concluded that the Sty/AAc copolymer with composition 20/80 wt % can be used as a contrilled water retainer for carrying of some substance in aquatic fields involving environmental treatments. Also, it could be concluded that the most important parameter affecting the swelling behaviour and characteristic of the prepared copolymer are the type of conversion due to chemical treatment, the pH of the medium and coonstituents of the prepared copolymer

  12. Surface grafted chitosan gels. Part I. Molecular insight into the formation of chitosan and poly(acrylic acid) multilayers

    DEFF Research Database (Denmark)

    Liu, Chao; Thormann, Esben; Claesson, Per M.;

    2014-01-01

    , provided information regarding composition, including water content, and ionization state of weak acidic and basic groups present in the thin composite film. Low molecular weight PAA, mainly in its protonated form, diffuses into and out of the composite film during adsorption and rinsing steps. The higher...

  13. Development of heterogenized catalyst systems for the synthesis of acrylic acid derivatives from carbon dioxide and ethylene

    OpenAIRE

    Prasetyo, Eko

    2015-01-01

    Use of CO2 as chemical feedstock represents one of the most sustainable ways for carbon recycling, generating high value products. Current industrial practices include the manufacture of urea, organic (poly)carbonates, and salicylic acid. CO2 can also be used to produce CO-rich syngas, which can be further processed to olefins, aldehydes, alcohols, or synthetic fuel via the Fischer-Tropsch process. Direct carboxylation with CO2 yielding carbonates, carbamates, carboxylates, or lactones is of ...

  14. Properties and mechanisms of drug release from matrix tablets containing poly(ethylene oxide) and poly(acrylic acid) as release retardants.

    Science.gov (United States)

    Zhang, Feng; Meng, Fan; Lubach, Joseph; Koleng, Joseph; Watson, N A

    2016-08-01

    The interactions between poly(ethylene oxide) (PEO) and poly(acrylic acid) (PAA) in aqueous medium at pH 6.8 were investigated in the current study. We have also studied the effect of interpolymer interactions and various formulation variables, including the molecular weight of PEO, the ratio between PEO and PAA, the crystallinity of PEO, and the presence of an acidifying agent, on the release of theophylline from matrix tablets containing both PEO and PAA as release retardants. At pH 6.8, the synergy in solution viscosity between PEO and PAA as the result of ion-dipole interaction was observed in this study. The release of theophylline from the matrix tablets containing physical mixtures of PEO and PAA was found to be a function of dissolution medium pH because of the pH-dependent interactions between these two polymers. Because of the formation of water insoluble interpolymer complex between PEO and PAA in aqueous medium at pH below 4.0, the release of theophylline was independent of PEO molecular weight and was controlled by Fickian diffusion mechanism in 0.01N hydrochloric acid solution. In comparison, the drug release was a function of PEO molecular weight and followed the anomalous transport mechanism in phosphate buffer pH 6.8. The presence of PAA exerted opposite effects on the release of theophylline in phosphate buffer pH 6.8. In one aspect, theophylline release was accelerated because the erosion of PAA was much faster than that of PEO at pH6.8. On the opposite aspect, theophylline release was slowed down because of the formation of insoluble complex inside the gel layer as the result of the acidic microenvironment induced by PAA, and the increase in the viscosity of the gel layer as the result of the synergy between PEO and PAA. These two opposite effects offset each other. As a result, the release of theophylline remained statistically the same even when 75% PEO in the formulation was replaced with PAA. In phosphate buffer pH 6.8, the release of

  15. Optical limiting response of multi-walled carbon nanotube-phthalocyanine nanocomposite in solution and when in poly (acrylic acid)

    Science.gov (United States)

    Sekhosana, Kutloano Edward; Nyokong, Tebello

    2016-08-01

    Bis{23-(3,4-di-yloxybenzoic acid)-(2(3), 9(10), 16(17), 23(24)-(hexakis-pyridin-3-yloxy phthalocyaninato)} dineodymium (III) acetate (3) is linked to amino-functionalized multi-walled carbon nanotubes (MWCNT) to form 3-MWCNT. Z-scan technique was employed to experimentally determine the nonlinear absorption coefficient from the open-aperture data. The limiting threshold values as low as 0.045 J cm-2 were found in solution. The conjugate (3-MWCNT) gave better optical limiting behavior than complex 3 alone.

  16. Development of radiation curable surface coating based on soybean oil. part I. preparation and characterization of acrylated oil

    International Nuclear Information System (INIS)

    An epoxy acrylate was synthesized from epoxidized soybean oil (ESOL) by using acrylic acid monomer. Triethyl amine (TEA) and hydroquinone were used as catalyst and inhibitor respectively. The epoxidized soybean oil acrylate (ESOLA) is done by introducing acrylic acid into oxirane groups of the epoxidized oil (ESOL). This reaction was confirmed by analytical data in terms of oxirane oxygen content, acid value, viscosity and spectroscopically analysis

  17. Electrospun Poly(acrylic acid)/Silica Hydrogel Nanofibers Scaffold for Highly Efficient Adsorption of Lanthanide Ions and Its Photoluminescence Performance.

    Science.gov (United States)

    Wang, Min; Li, Xiong; Hua, Weikang; Shen, Lingdi; Yu, Xufeng; Wang, Xuefen

    2016-09-14

    Combined with the features of electrospun nanofibers and the nature of hydrogel, a novel choreographed poly(acrylic acid)-silica hydrogel nanofibers (PAA-S HNFs) scaffold with excellent rare earth elements (REEs) recovery performance was fabricated by a facile route consisting of colloid-electrospinning of PAA/SiO2 precursor solution, moderate thermal cross-linking of PAA-S nanofiber matrix, and full swelling in water. The resultant PAA-S HNFs with a loose and spongy porous network structure exhibited a remarkable adsorption capacity of lanthanide ions (Ln(3+)) triggered by the penetration of Ln(3+) from the nanofiber surface to interior through the abundant water channels, which took full advantage of the internal adsorption sites of nanofibers. The effects of initial solution pH, concentration, and contact time on adsorption of Ln(3+) have been investigated comprehensively. The maximum equilibrium adsorption capacities for La(3+), Eu(3+), and Tb(3+) were 232.6, 268.8, and 250.0 mg/g, respectively, at pH 6, and the adsorption data were well-fitted to the Langmuir isotherm and pseudo-second-order models. The resultant PAA-S HNFs scaffolds could be regenerated successfully. Furthermore, the proposed adsorption mechanism of Ln(3+) on PAA-S HNFs scaffolds was the formation of bidentate carboxylates between carboxyl groups and Ln(3+) confirmed by FT-IR and XPS analysis. The well-designed PAA-S HNFs scaffold can be used as a promising alternative for effective REEs recovery. Moreover, benefiting from the unique features of Ln(3+), the Ln-PAA-S HNFs simultaneously exhibited versatile advantages including good photoluminescent performance, tunable emission color, and excellent flexibility and processability, which also hold great potential for applications in luminescent patterning, underwater fluorescent devices, sensors, and biomaterials, among others. PMID:27537710

  18. Unusually Stable Hysteresis in the pH-Response of Poly(Acrylic Acid) Brushes Confined within Nanoporous Block Polymer Thin Films.

    Science.gov (United States)

    Weidman, Jacob L; Mulvenna, Ryan A; Boudouris, Bryan W; Phillip, William A

    2016-06-01

    Stimuli-responsive soft materials are a highly studied field due to their wide-ranging applications; however, only a small group of these materials display hysteretic responses to stimuli. Moreover, previous reports of this behavior have typically shown it to be short-lived. In this work, poly(acrylic acid) (PAA) chains at extremely high grafting densities and confined in nanoscale pores displayed a unique long-lived hysteretic behavior caused by their ability to form a metastable hydrogen bond network. Hydraulic permeability measurements demonstrated that the conformation of the PAA chains exhibited a hysteretic dependence on pH, where different effective pore diameters arose in a pH range of 3 to 8, as determined by the pH of the previous environment. Further studies using Fourier transform infrared (FTIR) spectroscopy demonstrated that the fraction of ionized PAA moieties depended on the thin film history; this was corroborated by metal adsorption capacity, which demonstrated the same pH dependence. This hysteresis was shown to be persistent, enduring for days, in a manner unlike most other systems. The hypothesis that hydrogen bonding among PAA units contributed to the hysteretic behavior was supported by experiments with a urea solution, which disrupted the metastable hydrogen bonded state of PAA toward its ionized state. The ability of PAA to hydrogen bond within these confined pores results in a stable and tunable hysteresis not previously observed in homopolymer materials. An enhanced understanding of the polymer chemistry and physics governing this hysteresis gives insight into the design and manipulation of next-generation sensors and gating materials in nanoscale applications.

  19. Thin ZnO nanocomposite poly(styrene-acrylic acid) films on Si and SiO2 surfaces

    International Nuclear Information System (INIS)

    The properties and formation of self-assembled ZnO nanoclusters using polystyrene-based diblock copolymers are reported. The polystyrene-polyacrylic acid copolymer consisting of a majority block (polystyrene) and a minority block (polyacrylic acid) with a block number average molecular weight ratio of 16,500/4500 and a block repeat unit ratio of 159/63 was used in order to obtain self-assembly due to microphase separation with spherical morphology. The self-assembly of the inorganic nanoparticles was achieved at room temperature in the liquid phase using a ZnCl2 precursor dopant attached to the minority block, and both dry and wet chemical processing techniques compatible with semiconductor manufacturing were developed in order to convert the ZnCl2 precursor into ZnO. The polymer films were applied by standard spin-on photolithographic techniques on Si wafers with and without thermally grown SiO2 surface films. A study by X-ray photoelectron spectroscopy (XPS) confirmed the conversion of the ZnCl2 dopant precursor into ZnO within the copolymer matrix, and atomic force microscopy (AFM) showed the spherical morphology of the resultant ZnO nanoclusters. Conversion of the precursor into ZnO was achieved both by a wet chemical treatment and by developing a new dry chemical treatment process based on ozone exposure. The study showed that the dry treatment has better stability and shorter conversion exposure times on the Si surfaces than the wet treatment approach, resulting in lateral size distribution between 250 and 350 nm and height distribution between 80 and 130 nm for the ZnO nanoclusters

  20. Surface functionalisation of polypropylene hernia-repair meshes by RF-activated plasma polymerisation of acrylic acid and silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nisticò, Roberto, E-mail: roberto.nistico@unito.it [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rosellini, Andrea [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rivolo, Paola [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Faga, Maria Giulia [CNR-IMAMOTER, Strada delle Cacce 73, 10135 Torino (Italy); Lamberti, Roberta; Martorana, Selanna [Herniamesh S.r.l., Via F.lli Meliga 1/C, 10034 Chivasso (Italy); Castellino, Micaela [Center for Space Human Robotics, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Virga, Alessandro; Mandracci, Pietro [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Malandrino, Mery; Magnacca, Giuliana [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy)

    2015-02-15

    Graphical abstract: - Highlights: • Polypropylene meshes for hernioplasty were surface functionalised via plasma-polymerisation to confer adhesive properties. • Subsequently, silver nanoparticles were loaded to add antibacterial activity. • Materials were physico-chemical characterised and adhesive properties evaluated. - Abstract: Hernia diseases are among the most common and diffuse causes of surgical interventions. Unfortunately, still nowadays there are different phenomena which can cause the hernioplasty failure, for instance post-operative prostheses displacements and proliferation of bacteria in the surgical site. In order to limit these problems, commercial polypropylene (PP) and polypropylene/Teflon (PP/PTFE) bi-material meshes were surface functionalised to confer adhesive properties (and therefore reduce undesired displacements) using polyacrylic acid synthesized by plasma polymerisation (PPAA). A broad physico-chemical and morphological characterisation was carried out and adhesion properties were investigated by means of atomic force microscopy (AFM) used in force/distance (F/D) mode. Once biomedical devices surface was functionalised by PPAA coating, metallic silver nanoparticles (AgNPs) with antimicrobial properties were synthesised and loaded onto the polymeric prostheses. The effect of the PPAA, containing carboxylic functionalities, adhesive coating towards AgNPs loading capacity was verified by means of X-ray photoelectron spectroscopy (XPS). Preliminary measurement of the Ag loaded amount and release in water were also investigated via inductively coupled plasma atomic emission spectroscopy (ICP-AES). Promising results were obtained for the functionalised biomaterials, encouraging future in vitro and in vivo tests.

  1. Analysis and Testing of Bisphenol A—Free Bio-Based Tannin Epoxy-Acrylic Adhesives

    OpenAIRE

    Shayesteh Jahanshahi; Antonio Pizzi; Ali Abdulkhani; Alireza Shakeri

    2016-01-01

    A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET) and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, 13C-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 °C for 12 h. FT-MIR, 13C-NMR and MALDI-TOF analysis have...

  2. Matrix tablets based on thiolated poly(acrylic acid): pH-dependent variation in disintegration and mucoadhesion.

    Science.gov (United States)

    Guggi, Davide; Marschütz, Michaela K; Bernkop-Schnürch, Andreas

    2004-04-15

    This study examined the influence of the pH on the mucoadhesive and cohesive properties of polyarcylic acid (PAA) and thiolated PAA. The pH of PAA (molecular mass: 450 kDa) and of a corresponding PAA-cysteine conjugate was adjusted to 3, 4, 5, 6, 7 and 8. The amount of immobilised thiol groups and disulfide bonds was determined via Ellman's reagent. Tablets were compressed out of each pH-batch of both thiolated and unmodified PAA and the swelling behaviour, the disintegration time and the mucoadhesiveness were evaluated. The amount of thiol/disulfide groups per gram thiolated PAA of pH 3 and pH 8 was determined to be 332 +/- 94 micromol and 162 +/- 46 micromol, respectively. The thiolated PAA tablets displayed a minimum four-fold higher water uptake compared to unmodified PAA tablets. A faster and higher water uptake of both polymer types was observed above pH 5. Thiolated polymer tablets showed a 3-20-fold more prolonged disintegration time than unmodified PAA tablets. The cohesiveness of PAA-cysteine conjugate increased at higher pH, whereas the unmodified PAA behaved inversely. A 3-7-fold stronger mucoadhesiveness was observed for the PAA-cysteine conjugate tablets compared to unmodified PAA tablets. For both thiolated and unmodified polymer the mucoadhesiveness was 2-4-fold enhanced below pH 5. The difference in mucoadhesion between the two polymer types was most pronounced at these lower pH values. In this study substantial information regarding the pH-dependence of mucoadhesion and cohesion of unmodified polyacrylates and of thiolated polyacrylates is provided, representing helpful basic information for an ameliorated deployment of these polymers. PMID:15072786

  3. Rapid removal of copper with magnetic poly-acrylic weak acid resin: Quantitative role of bead radius on ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Lichun; Shuang, Chendong; Liu, Fuqiang, E-mail: jogia@163.com; Li, Aimin, E-mail: liaimin@nju.edu.cn; Li, Yan; Zhou, Yang; Song, Haiou

    2014-05-01

    Highlights: • The equilibrium adsorption amount of Cu{sup 2+} onto NDMC was 267.2 mg/g. • Initial adsorption rate of NDMC was 4 and 8 times that of C106 and IRC-748. • External surface area was determined to be the key factor in rate-controlling. • Adsorption amount onto NDMC was not influenced by Na{sup +} concentration. • 0.01 mM HCl solution could effectively desorb Cu{sup 2+}. - Abstract: A novel magnetic weak acid resin NDMC was self-synthesized for the removal of Cu{sup 2+} from aqueous solutions. NDMC showed superior properties on the removal of Cu{sup 2+} compared to commercial resins C106 and IRC-748, which was deeply investigated by adsorption isotherms and kinetic tests. The equilibrium adsorption amount of Cu{sup 2+} onto NDMC (267.2 mg/g) was almost twice as large as that onto IRC-748 (120.0 mg/g). The adsorption kinetics of Cu{sup 2+} onto the three resins fitted well with the pseudo-second-order equation. The initial adsorption rate h of NDMC was about 4 times that of C106 and nearly 8 times that of IRC-748 at the initial concentration of 500 mg/L. External surface area was determined to be the key factor in rate-controlling by further analyzing the adsorption thermodynamics, kinetics parameters and physicochemical properties of the resins. NDMC resin with the smallest bead radius possessed the largest external surface and therefore exhibited the fastest kinetics. The adsorption amount of Cu{sup 2+} onto NDMC was not influenced as the concentration of Na{sup +} increased from 1.0 to 10.0 mM/L. Dilute HCl solution could effectively desorb Cu{sup 2+}. NDMC demonstrated high stability during 10 adsorption/desorption cycles, showing great potential in the rapid removal of Cu{sup 2+} from wastewater.

  4. 纳米腐植酸/丙烯酸-丙烯酰胺-蒙脱土复合型树脂的制备与表征%Preparation and characterization of nanoscale humic acid /poly(acrylic acid-acryl amide)-co-montorillonite composite resin

    Institute of Scientific and Technical Information of China (English)

    程亮; 侯翠红; 徐丽; 雒廷亮; 张保林; 刘国际

    2016-01-01

    The composite resins based on (acrylic acid-acrylamide)-motorillonite/nano humic acid were prepared by aqueous solution polymerization,using methylene-bis-acrylamide as cross-linking agent,potassium persulfate as initiator,acrylic acid,acrylamide,nano humic acid and modified montmorillonite as material.The effects of the monomer ratio (mass ratio ),nano-humic acid content,reaction temperature were systematically studied through single factor and orthogonal experiment.The optimum conditions were as follows:the monomer ratio 3:7 ,nano humic acid content 15%(mass fraction),reaction temperature 65℃,neutralization degree 80%(mass fraction), cross-linking agent content 0.05% (mass fraction),and initiator content 1.0% (mass fraction).The water absorption rate and salt absorption rate of the prepared composite resins were 998.90 g/g and 102.59 g/g, respectively.The product was characterized by FT-IR,SEM and TG-DSC,and the results showed that the grafting reaction took place among nanoscale humic acid and acrylamide,and ether bond emerged;the surface was rough and had loose structure,there were also many holes,voids and pits;it had a good thermal stability.%以N,N-亚甲基双丙烯酰胺为交联剂,过二硫酸钾为引发剂,丙烯酸、丙烯酰胺、纳米腐植酸及改性蒙脱土为原料,采用水溶液聚合法制备了丙烯酸-丙烯酰胺/纳米腐植酸基复合型树脂.通过单因素及正交实验系统考察了单体比(质量比)、纳米腐植酸用量、反应温度等因素对复合型树脂吸液倍率的影响.最适宜制备工艺条件为:单体比3:7,纳米腐植酸用量为15%,反应温度65℃,中和度80%,交联剂0.05%,引发剂1.0%,所制备的复合型树脂吸水和吸盐倍率分别为998.90 g/g及102.59 g/g.用FT-IR,SEM及TG-DSC等对产物进行表征,结果表明:纳米腐植酸与丙烯酰胺发生接枝反应,产生了醚键;其表面结构疏松且粗糙,呈现较多孔洞、空隙及凹坑;热稳定性较好.

  5. Synthesis of Superabsorbent Polymer of Cassava Starch Grafting Acrylic Acid%木薯淀粉-丙烯酸接枝共聚合成高吸水性树脂

    Institute of Scientific and Technical Information of China (English)

    樊红日; 张立颖; 黎洪; 尹丽

    2011-01-01

    [ Objective] The research aimed to study the synthesis of superabsorbent polymer by cassava starch. [ Method] Using acrylic acid and cassava starch as raw material, ammonium persulfate and anhydrous sodium sulfite as initiator, superabsorbent polymer was synthesized by aqueous solution polymerization. The effect of monomer-starch ratio, reaction temperature, reaction time, acrylic acid and its neutralization degree and the initiators dosage on the water absorption of the product were investigated. [ Result ] Water absorbency in deionized water and salt water of 0.9% NaCl were 1 844 g/g and 224 g/g respectively at room temperature within 1 h. [ Conclusion ] The study provided scientific basis for preparing superabsorbent polymer with acrylic acid and cassava starch.%[目的]研究木薯淀粉合成高吸水性树脂.[方法]以木薯淀粉和丙烯酸单体为原料,过硫酸铵-亚硫酸钠为引发剂,通过水溶液聚合法制得淀粉基高吸水性树脂.考察了淀粉与单体配比、反应温度、反应时间、中和度和引发剂用量等因素对产品吸水率的影响.[结果]得出产品在室温下1 h内吸去离子水1 844 g/g、0.9%NaCl盐水224 g/g.[结论]该研究为以木薯淀粉与丙烯酸为原料制备高吸水树脂提供科学依据.

  6. 腐植酸钾/丙烯酸型保水剂的合成及性能研究%Synthesis and performance of potassium humate/acrylic acid water-retaining agent

    Institute of Scientific and Technical Information of China (English)

    魏友华; 顾铭茜; 季燕; 陈洪龄

    2013-01-01

    以腐植酸钾(KHA)与丙烯酸(AA)为原料,N,N-亚甲基双丙烯酰胺为交联剂,过K2SO4为引发剂,进行水溶液聚合,制备得到腐植酸钾/丙烯酸高吸水性保水树脂.研究了反应物比例、反应温度、交联剂、引发剂用量、中和度等因素对产物性能的影响.考察了产物的热稳定性、保水性能、耐电解质和重复使用性能.结果表明,树脂最大吸水率为609g·g-1,耐盐性良好,50℃环境温度下9h保水树脂仍有94.2%的保水率.%Potassium humate/acrylic acid water retention resin was prepared from potassium humate and acrylic acid by aqueous polymerization with the crosslinking agent of N, N-methylene-bis-acrylamide and the initiator of potassium persulfate. The effect of reactant ratio, reaction temperature, the amount of cross-linking agent and initiator, and the neutralization degree were investigated. In addition, thermal stability, water retention and reuse ability of the products were studied. Results show that the maximum water absorption ability of potassium humate/acrylic acid superabsorbent resin was 609g·g-1 for distilled water. At the environment temperature 50℃, the water retention resin still have 94.2% of the water retention rate after 9 hour.

  7. Poly-N-Isopropylacrylamide/acrylic Acid Copolymers for the Generation of Nanostructures at Mica Surfaces and as Hydrophobic Host Systems for the Porin MspA from Mycobacterium smegmatis.

    Science.gov (United States)

    Gamage, Pubudu; Basel, Matthew T; Lovell, Kimberly; Pokhrel, Megh Raj; Battle, Deletria; Ito, Takashi; Pavlenok, Mikhail; Niederweis, Michael; Bossmann, Stefan H

    2009-09-17

    The work presented here aims at utilizing poly-N-isopropyl-acrylamide/acrylic acid copolymers to create nanostructured layers on mica surfaces by a simple spin-casting procedure. The average composition of the copolymers determined by elemental analysis correlates excellently with the feed composition indicating that the radical polymerization process is statistical. The resulting surfaces were characterized by Atomic Force Microscopy (magnetic AC-mode) at the copolymer/air interface. Postpolymerization modification of the acrylic acid functions with perfluoro-octyl-iodide decreased the tendency towards spontaneous formation of nanopores. Crosslinking of individual polymer chains permitted the generation of ultraflat layers, which hosted the mycobacterial channel protein MspA, without compromising its channel function. The comparison of copolymers of very similar chemical composition that have been prepared by living radical polymerization and classic radical polymerization indicated that differences in polydispersity played only a minor role when poly-N-isopropyl-acrylamide/acrylic acid copolymers were spincast, but a major role when copolymers featuring the strongly hydrophobic perfluoro-octyl-labels were used. The mean pore diameters were 23.8+/-4.4 nm for P[(NIPAM)(95.5)-co-(AA)(4.5)] (PDI (polydispersity index)=1.55) and 21.8+/-4.2 nm for P[(NIPAM)(95.3)-co-(AA)(4.7)] (PDI=1.25). The depth of the nanopores was approx. 4 nm. When depositing P[(NIPAM)(95)-co-(AA)(2.8)-AAC(8)F(17 2.2)] (PDI=1.29) on Mica, the resulting mean pore diameter was 35.8+/-7.1 nm, with a depth of only 2 nm. PMID:20161351

  8. Synthesis and Characterization of Acrylamide and/or Acrylic Acid Grafted onto Corn Starch bv Irradiation%淀粉-丙烯酸-丙烯酰胺三元接枝物的制备及性质研究

    Institute of Scientific and Technical Information of China (English)

    郭军; 黄劲松; 杜先锋

    2011-01-01

    在60Co间歇式共辐射条件下探讨了淀粉与丙烯酸和丙烯酰胺流变相态的接枝共聚反应;采用FTIR和SEM对接枝产物共聚物进行了结构表征;考察了丙烯酰胺和丙烯酸盐单体的配比、原料配比、辐射剂量等因素对聚合物吸水率、耐盐性等的影响.结果表明,在没有添加任何化学引发剂的情况下可以得到较高耐盐性和高吸水速率的淀粉-丙烯酸-丙烯酰胺共聚物,克服了传统生产方法中耐盐性低、吸水速度慢、高污染、高耗能等问题.%The grafting of acrylamide and/or acrylic acid onto starch by 60Co radiation as an initiator was studied in conditions of intermittent This copolymerization allowed for measurement of important parameters, including the glucose monomer-to-starch ratio and the water absorption of the graft copolymer in salt solutions. The acrylamide-to-acrylic acid ratio, were measured at the radiation dose used in kGy. The graft-copolymerization reaction mechanism and morphology of the copolymer were investigated using FTIR scanning electron microscopy. The effects of the stuff-proportion, radiation does, starch pasting, neutralization degree of acrylic acid, radiation does-rate on the graft copolymerization reaction and absorption capacity of high water were investigated. The results showed that the grafting of acrylic acid on starch could be carried out successfully by 60Co radiation without any chemic initiator. Overcome the traditional production methods with low salt tolerance, slowly water absorption, pollution, high-energy consumption and other problems.

  9. Synthesis and characterization of chitosan-graft-poly(acrylic acid)/rice husk ash hydrogels composites; Sintese e caracterizacao de hidrogeis compositos de cinza da casca de arroz e quitosana enxertada com poli(acido acrilico)

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Francisco H.A. [Universidade Estadual Vale do Acarau - UVA, Sobral, CE (Brazil); Lopes, Gabriel V.; Pereira, Antonio G.B.; Fajardo, Andre R.; Muniz, Edvani C. [Universidade Estadual de Maringa - UEM, PR (Brazil)

    2011-07-01

    According to environmental concerns, super absorbent hydrogel composites were synthesized based on rice husk ash (RHA), an industrial waste, and Chitosan-graft-poly(acrylic acid). The WAXS and FTIR data confirmed the syntheses of hydrogel composites. The effect of crystalline or amorphous RHA on water uptake was investigated. It was found that the RHA in crystalline form induces higher water capacity (W{sub eq}) of composites hydrogels due to the fact that the intra-interactions among silanol groups on RHA make available new sites in the polymer matrix, which could interact to water. (author)

  10. Multifunctional electroactive electrospun nanofiber structures from water solution blends of PVA/ODA-MMT and poly(maleic acid-alt-acrylic acid): effects of Ag, organoclay, structural rearrangement and NaOH doping factors

    Science.gov (United States)

    Şimşek, Murat; Rzayev, Zakir M. O.; Bunyatova, Ulviya

    2016-06-01

    Novel multifunctional colloidal polymer nanofiber electrolytes were fabricated by green reactive electrospinning nanotechnology from various water solution/dispersed blends of poly (vinyl alcohol-co-vinyl acetate) (PVA)/octadecyl amine-montmorillonite (ODA-MMT) as matrix polymer nanocomposite and poly(maleic acid-alt-acrylic acid) (poly(MAc-alt-AA) and/or its Ag-carrying complex as partner copolymers. Polymer nanofiber electrolytes were characterized using FTIR, XRD, thermal (DSC, TGA-DTG), SEM, and electrical analysis methods. Effects of partner copolymers, organoclay, in situ generated silver nanoparticles (AgNPs), and annealing procedure on physical and chemical properties of polymer composite nanofibers were investigated. The electrical properties (resistance, conductivity, activation energy) of nanofibers with/without NaOH doping agent were also evaluated. This work presented a structural rearrangement of nanofiber mats by annealing via decarboxylation of anhydride units with the formation of new conjugated double bond sites onto partner copolymer main chains. It was also found that the semiconductor behaviors of nanofiber structures were essentially improved with increasing temperature and fraction of partner copolymers as well as presence of organoclay and AgNPs in nanofiber composite.

  11. Multifunctional electroactive electrospun nanofiber structures from water solution blends of PVA/ODA–MMT and poly(maleic acid-alt-acrylic acid): effects of Ag, organoclay, structural rearrangement and NaOH doping factors

    Science.gov (United States)

    Şimşek, Murat; Rzayev, Zakir M. O.; Bunyatova, Ulviya

    2016-06-01

    Novel multifunctional colloidal polymer nanofiber electrolytes were fabricated by green reactive electrospinning nanotechnology from various water solution/dispersed blends of poly (vinyl alcohol-co-vinyl acetate) (PVA)/octadecyl amine-montmorillonite (ODA–MMT) as matrix polymer nanocomposite and poly(maleic acid-alt-acrylic acid) (poly(MAc-alt-AA) and/or its Ag-carrying complex as partner copolymers. Polymer nanofiber electrolytes were characterized using FTIR, XRD, thermal (DSC, TGA–DTG), SEM, and electrical analysis methods. Effects of partner copolymers, organoclay, in situ generated silver nanoparticles (AgNPs), and annealing procedure on physical and chemical properties of polymer composite nanofibers were investigated. The electrical properties (resistance, conductivity, activation energy) of nanofibers with/without NaOH doping agent were also evaluated. This work presented a structural rearrangement of nanofiber mats by annealing via decarboxylation of anhydride units with the formation of new conjugated double bond sites onto partner copolymer main chains. It was also found that the semiconductor behaviors of nanofiber structures were essentially improved with increasing temperature and fraction of partner copolymers as well as presence of organoclay and AgNPs in nanofiber composite.

  12. Pyrolysis of carbonaceous particles and properties of Carbonaceous-g-Poly (acrylic acid-co-acrylamide superabsorbent polymer for agricultural applications

    Directory of Open Access Journals (Sweden)

    Ghazali S.

    2016-01-01

    Full Text Available Utilisation of fertilizer and water are very important in determining the production of agriculture nowadays. The excessive use of fertilizer in plantation somehow could leads to environmental pollution. The present study reported a synthesis of controlled release water retention (CRWR fertilizer coating with superabsorbent polymer (SAPs. Superabsorbent polymer (SAPs are polymers that have ability to absorb and retain large amounts of water relative to their own mass. The presence of coating layer of SAPs on fertilizer granules was believed could reduce excessive used of fertilizer by controlling their dissolution rates and also reduce the environmental pollution. In this study, the effect on the addition of carbonaceous filler in SAPs on the water absorbency was also be compared with control SAPs (without carbonaceous particles. In this study, the carbonaceous filler were obtained from pyrolysis process of empty fruit bunch (EFB biomass. The synthesized of SAPs and carbonaceous-SAPs were carried out via solution polymerization technique by using monomer of poly(acrylic acid (AA, acrylamide (AM, cross linker, methylene bisacrylamide (MBA and initiator, ammonium peroxodisulfate (APS that partially neutralized with sodium hydroxide (NaOH. The CRWR fertilizer was later be prepared by coated the fertilizer granule with SAPs and carbonaceous-SAPs. The water absorbency, morphology and the bonding formation of both CRWR fertilizer were investigated by using tea-beg method, Scanning Electron Microscopy (SEM and Fourier Transform Infrared Spectrophotometer (FTIR, respectively. Moreover, the water retention studies was conducted in order to investigate the efficiency of CRWR coated with SAP and carbonaceous-SAP in retaining the water content in different soil (organic and top soil. Based on the results, the CRWR fertilizer that was coated with carbonaceous-SAP had higher water absorbency value than the CRWR fertilizer without carbonaceous-SAP. Meanwhile

  13. Acrylic purification and coatings

    CERN Document Server

    ,

    2012-01-01

    Radon (Rn) and its decay daughters are a well-known source of background in direct WIMP detection experiments, as either a Rn decay daughter or an alpha particle emitted from a thin inner surface layer of a detector could produce a WIMP-like signal. Different surface treatment and cleaning techniques have been employed in the past to remove this type of contamination. A new method of dealing with the problem has been proposed and used for a prototype acrylic DEAP-1 detector. Inner surfaces of the detector were coated with a layer of ultra pure acrylic, meant to shield the active volume from alphas and recoiling nuclei. An acrylic purification technique and two coating techniques are described: a solvent-borne (tested on DEAP-1) and solvent-less (being developed for the full scale DEAP-3600 detector).

  14. 丙烯酸接枝邻苯二酚衍生物的二次聚合%Novel Copolymers Synthesis by Second Polymerization of Acrylate Acid Grafted 1,2-Dihydroxylbenzene Derivatives

    Institute of Scientific and Technical Information of China (English)

    黄瑶; 朱召进; 徐景坤; 卢宝阳; 岳瑞瑞

    2012-01-01

    合成了2种聚合前驱体邻苯二丙烯酸酯(o-PDA)和2-甲氧基苯丙烯酸酯(2-MOPA),分别通过与丙烯酸(AA)自由基共聚得到邻苯二丙烯酸酯-丙烯酸共聚物(O1)和2-甲氧基苯丙烯酸酯-丙烯酸共聚物(O2).产物邻苯二酚(o-DHB)-O1(质量比1∶1)和1-羟基-2-甲氧基苯(HMOB)-O2(质量比1∶1)分别在乙腈/二氯甲烷-三氟化硼乙醚体系中直接阳极氧化聚合获得交联网状共聚物P1和P2.P1和P2均可溶于DMSO,而难溶于ACN,DCM和THF等有机溶剂.通过UV-Vis,FTIR和1H NMR对交联共聚物膜的结构进行了表征.AA的引入不仅可以增加链的柔韧性,而且提高了共聚物的力学性能.而o-DHB/HMOB的引入极大地减弱了单体的聚合位阻,实现了单体的二次聚合,同时也增强了单体及聚合物的电化学活性.荧光光谱显示,得到的2种交联共聚物膜分别在415和487 nm处有较强的发射峰,表明共聚物仍具有良好的蓝色发光性能,且聚丙烯酸结构的引入并没有对聚邻苯二酚(Po-DHB)和聚(1-羟基-2-甲氧基苯)(PHMOB)产生较大的荧光猝灭作用.热重分析曲线(TGA)表明2种交联共聚物膜均具有较高的热稳定性.%Two novel acrylate functionalized monomers o-phenylene diacrylate(o-PDA) and 2-methoxyphenyl acrylate(2-MOPA) were designed and synthesized. Through radical copolymerization of o-PDA/2-MOPA with acrylic acid( AA), two precursor polymers, oligo ( o-phenylene diacrylate-eo-acrylic acid) (01) and oligo (2-methoxyphenyl acrylate-co-acrylic acid ) ( 02 ) were obtained. Cross-linked poly ( O1-co-o-dihydroxy-benzene)(Pl) and poly(O2-co-l-hydroxy-2-methoxybenzene) (P2) films were achieved by electrochemical polymerization of monomer mixtures of o-DHB-O1 and HMOB-O2, respectively. UV-Vis, FTIR and 1H NMR spectra were used to characterize the structures of the copolymers. Since AA and o-DHB/HMOB were introduced into the polymerization processes, the steric hindrance of the monomers were weakened extremely, and

  15. Synthesis of linear low-density polyethylene-g-poly (acrylic acid)-co-starch/organo-montmorillonite hydrogel composite as an adsorbent for removal of Pb(Ⅱ) from aqueous solutions

    Institute of Scientific and Technical Information of China (English)

    Maryam Irani; Hanafi Ismail; Zulkifli Ahmad; Maohong Fan

    2015-01-01

    The purpose of this work is to remove Pb(Ⅱ) from the aqueous solution using a type of hydrogel composite.A hydrogel composite consisting of waste linear low density polyethylene,acrylic acid,starch,and organo-montmorillonite was prepared through emulsion polymerization method.Fourier transform infrared spectroscopy (FTIR),Solid carbon nuclear magnetic resonance spectroscopy (CNMR)),silicon-29 nuclear magnetic resonance spectroscopy (Si NMR)),and X-ray diffraction spectroscope ((XRD) were applied to characterize the hydrogel composite.The hydrogel composite was then employed as an adsorbent for the removal of Pb(Ⅱ) from the aqueous solution.The Pb(Ⅱ)-loaded hydrogel composite was characterized using Fourier transform infrared spectroscopy (FTIR)),scanning electron microscopy (SEM)),and X-ray photoelectron spectroscopy ((XPS)).From XPS results,it was found that the carboxyl and hydroxyl groups of the hydrogel composite participated in the removal of Pb(Ⅱ).Kinetic studies indicated that the adsorption of Pb(Ⅱ)followed the pseudo-second-order equation.It was also found that the Langmuir model described the adsorption isotherm better than the Freundlich isotherm.The maximum removal capacity of the hydrogel composite for Pb(Ⅱ) ions was 430 mg/g.Thus,the waste linear low-density polyethylene-g-poly (acrylic acid)-co-starch/organo-montmorillonite hydrogel composite could be a promising Pb(Ⅱ) adsorbent.

  16. Biodegradability of chitosan-polyvinylalcohol-acrylic acid superabsorbent polymers%壳聚糖-聚乙烯醇-丙烯酸高吸水树脂的生物降解性能研究

    Institute of Scientific and Technical Information of China (English)

    陈嘉恒; 吴国杰; 廖宗祺; 陈倩瑜

    2013-01-01

    采用培养基培养方法,考察了黑曲霉(Aspergillus flavus)和白僵菌(Beauveria bassiana)利用壳聚糖-聚乙烯醇-丙烯酸高吸水树脂中碳源的生长情况,并对高吸水树脂作为未来生物农药白僵菌的载体进行了初步探索。扫描电镜分析表明,壳聚糖-聚乙烯醇-丙烯酸高吸水树脂具有一定的生物降解性。%The growth of Aspergillus flavus and Beauveria bassiana was examined in the medium with the carbon source of Chitosan-polyvinylalcohol-Acrylic acid Superabsorbent Polymers .The use of superabsor-bent polymers as a vector for biopesticide beauveria bassiana was prospected .The scanning electron mi-croscope analysis showed that Chitosan-polyvinylalcohol-Acrylic acid Superabsorbent Polymers possesses certain biodegradability .

  17. Hyperbranched urethane-acrylates

    Directory of Open Access Journals (Sweden)

    Tasić Srba

    2004-01-01

    Full Text Available The synthesis, characterization and UV-curing of hyperbranched urethaneacrylates (HB-UA were investigated in this study. They were evaluated as oli-gomers in model UV curable coatings. HB-UAs were synthesized by reaction of an aliphatic hyperbranched polyester of the second generation (HBRG2 and an isocyanate adduct, obtained by the reaction of isophoronediisocyana-te and different hydroxy alkyl acrylates. Their thermal properties and viscosities depend on the degree of modification of HBRG2 and the type of hydroxy alkyl acrylate used. The introduction of a flexible alkoxylated spacer between the HBP core and acrylate end groups reduces steric hindrance by moving the cross linkable acrylate groups away from the HBP core and increase its reactivity. Due to the presence of abstractable H-atoms in the α-position to the ether links, HB-UAs based on poly(ethylene oxide monoacrylate are very reactive and do not show oxygen inhibition. The obtained coatings combine a high cross linking density with flexible segments between the cross links, which results in a good compromise between hardness and flexibility and have the potential to be used in different UV-curing applications.

  18. Studies on the hydrolysis of biocompatible acrylic polymers having aspirin-moieties.

    Science.gov (United States)

    Gu, Z W; Li, F M; Feng, X D; Voong, S T

    1983-01-01

    Both the homogeneous and heterogeneous hydrolysis of five new acrylic polymers having aspirin-moieties, i.e. polymers of beta-(acetylsalicylyloxy)ethyl methacrylate, beta-(acetylsalicylyloxy) propyl methacrylate,beta-(acetylsalicylyloxy) ethyl acrylate, beta-hydroxy-gamma-(acetylsalicylyloxy) propyl methacrylate, beta-hydroxy-gamma-(acetylsalicylyloxy) propyl acrylate were investigated in acidic or alkaline medium at 30 degrees C or 60 degrees C, respectively. It was observed that the chief hydrolyzed product is always aspirin with minor amount of salicylic acid.

  19. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  20. Poly(ethylene-co-acrylic acid)-g-poly(ethylene glycol) graft copolymer templated synthesis of mesoporous TiO{sub 2} thin films for quasi-solid-state dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Rajkumar; Jung, Ye Eun; Kim, Dong Jun; Kim, Sang Jin; Kim, Jong Hak, E-mail: jonghak@yonsei.ac.kr

    2014-02-03

    An amphiphilic graft copolymer, poly(ethylene-co-acrylic acid)-graft-poly(ethylene glycol) (PEAA-g-PEG), consisting of a PEAA backbone and PEG side chains was synthesized via an esterification reaction. {sup 1}H nuclear magnetic resonance and Fourier-transformed infrared analysis demonstrated esterification between carboxylic acid of PEAA and hydroxyl group of PEG. Small angle X-ray scattering results revealed that the crystalline domain spacing of PEAA increased from 11.3 to 12.8 nm upon using a more polar solvent with a higher affinity for poly(acrylic acid), while the crystalline domain spacing of PEAA disappeared with PEG grafting, indicating structural change to an amorphous state. Mesoporous TiO{sub 2} thin films were synthesized via a sol–gel reaction using PEAA-g-PEG graft copolymer as a structure-directing agent. The hydrophilically-preformed TiO{sub 2} nanoparticles were selectively confined in the hydrophilic PEG domains of the graft copolymer, and mesoporous TiO{sub 2} thin films were formed, as confirmed by scanning electron microscopy. The morphology of TiO{sub 2} films was tunable by varying the concentrations of polymer solutions and the amount of preformed TiO{sub 2}. A quasi-solid-state dye-sensitized solar cell fabricated with PEAA-g-PEG templated TiO{sub 2} film exhibited an energy conversion efficiency of 3.8% at 100 mW/cm{sup 2}, which was greater than that of commercially-available paste (2.6%) at a similar film thickness (3 μm). The improved performance was due to the larger surface area for high dye loading and organized structure with good interconnectivity. - Highlights: • Poly(ethylene-co-acrylic acid)-g-poly(ethylene glycol) (PEAA-g-PEG) graft copolymer is synthesized. • Amphiphilic PEAA-g-PEG acts as a structure directing agent. • Mesoporous TiO{sub 2} thin films are prepared by sol–gel reaction using PEAA-g-PEG template. • Efficiency of DSSC with templated TiO{sub 2} is greater than with commercial TiO{sub 2} paste.

  1. Poly(ethylene-co-acrylic acid)-g-poly(ethylene glycol) graft copolymer templated synthesis of mesoporous TiO2 thin films for quasi-solid-state dye sensitized solar cells

    International Nuclear Information System (INIS)

    An amphiphilic graft copolymer, poly(ethylene-co-acrylic acid)-graft-poly(ethylene glycol) (PEAA-g-PEG), consisting of a PEAA backbone and PEG side chains was synthesized via an esterification reaction. 1H nuclear magnetic resonance and Fourier-transformed infrared analysis demonstrated esterification between carboxylic acid of PEAA and hydroxyl group of PEG. Small angle X-ray scattering results revealed that the crystalline domain spacing of PEAA increased from 11.3 to 12.8 nm upon using a more polar solvent with a higher affinity for poly(acrylic acid), while the crystalline domain spacing of PEAA disappeared with PEG grafting, indicating structural change to an amorphous state. Mesoporous TiO2 thin films were synthesized via a sol–gel reaction using PEAA-g-PEG graft copolymer as a structure-directing agent. The hydrophilically-preformed TiO2 nanoparticles were selectively confined in the hydrophilic PEG domains of the graft copolymer, and mesoporous TiO2 thin films were formed, as confirmed by scanning electron microscopy. The morphology of TiO2 films was tunable by varying the concentrations of polymer solutions and the amount of preformed TiO2. A quasi-solid-state dye-sensitized solar cell fabricated with PEAA-g-PEG templated TiO2 film exhibited an energy conversion efficiency of 3.8% at 100 mW/cm2, which was greater than that of commercially-available paste (2.6%) at a similar film thickness (3 μm). The improved performance was due to the larger surface area for high dye loading and organized structure with good interconnectivity. - Highlights: • Poly(ethylene-co-acrylic acid)-g-poly(ethylene glycol) (PEAA-g-PEG) graft copolymer is synthesized. • Amphiphilic PEAA-g-PEG acts as a structure directing agent. • Mesoporous TiO2 thin films are prepared by sol–gel reaction using PEAA-g-PEG template. • Efficiency of DSSC with templated TiO2 is greater than with commercial TiO2 paste

  2. Properties of Acrylic Acid Resin Coating Materials Modified by Carbon Nanotubes%碳纳米管改性丙烯酸树脂涂饰材料的性能研究

    Institute of Scientific and Technical Information of China (English)

    孙友昌; 马建中; 鲍艳; 刘海腾; 于玉龙

    2011-01-01

    Firstly, carbon nanotubes were modified and purified by the mix acids, then surface properties of carbon nanotubes were analyzed with the help of the infrared detector. Vinyl leather finishing agent was modified by carbon nanotubes using physical blending and in - situ emulsion polymerization. Tensile strength, elongation at break and water resistance of acrylic resin mem- brane nano- composite coating agent were determined. The results show that carbon nanotubes has the obvious enhancement toughening effect to acrylic resin membrane. Acrylic resin modified by carbon nanotubes has better tensile strength and elongation at break with an increase in the amount of carbon nanotubes, but has worse water resistance. Acrylic resin membrane modified by carbon nanotubes using physical blending and in - situ emulsion polymerization, the comprehensive performance is the best when the dosage of CNTs respectively is 0.04% and 0. 03%. Ultrasonic treatment will decrease the tensile strength and elongation at break, but the water resistance of the film will be increased slightly.%采用混酸对碳纳米管(CNTs)进行改性和纯化,并以此为原料,分别采用物理共混与原位乳液聚合法制备碳纳米管改性丙烯酸树脂皮革涂饰剂,将制备的丙烯酸树脂乳液分别成膜,并对所成薄膜的抗张强度、断裂伸长率、耐水性等进行测定。结果表明:碳纳米管对丙烯酸树脂薄膜有明显的增强增韧效果,随着碳纳米管用量的增加,薄膜的抗张强度、断裂伸长率增加,但耐水性略有下降。采用物理共混法与原位乳液聚合法改性丙烯酸树脂乳液,当CNTs的用量分别为0.04%和0.03%时,改性丙烯酸树脂薄膜的综合性能最好。对改性后的乳液进行超声处理,可使

  3. Synthesis of highly carboxylate acrylic resins for leather impregnation

    OpenAIRE

    Ollé Otero, Lluís; Solé, M.M.; Shendrik, Alexander; Labastida, L.; Bacardit Dalmases, Anna

    2012-01-01

    This work describes the synthesis of new leather finishing acrylic resins. Four resins ware synthesized varying the concentration of ethyl acrylate, and metracrylic acid. Sodium lauryl sulphate was used as emulsifying system. By means of an experimental design, an optimal resin for leather impregnation was defined. The results obtained indicated that the variation of the monomer concentration influences the resin properties, the hardness of the film, and the penetration into the leather. Most...

  4. 聚(丙烯酸-丙烯酰胺)高吸水树脂的制备及性能研究%Preparation and properties of acrylic acid and acrylamid superabsorbent copolymer

    Institute of Scientific and Technical Information of China (English)

    刘玉贵; 张瑾; 朱忠其; 刘强; 柳清菊

    2013-01-01

    The acrylic acid and acrylamide (PAA-AM) superabsorbent copolymer was synthesized by inverse-suspension polymerization with cyclohexane as dispersant, Span80 as suspension stabilizer, acrylic acid (AA) and acrylamide (AM) as comonomer, potassium persulfate as initiator, N, N'-methylene-bis-acrylamide as crosslinking agent. The influence of neutralization degree of AA, mass ratio of acrylic acid (AA) to acrylamide (AM), the amount of crosslinking agent and initiator, and reaction temperature on the absorption capability of water and salt solution were investigated. The results show that the water absorbency of the superabsorbent polymer prepared at the optimum condition in deionized water and in 0. 9%NaCl solution is about 1282 and 109g/g, respectively, and under the same conditions, the sample has more excellent water absorption and salt-resistance, which compares with the similar products of the SNF (French) production.%以环己烷为溶剂,Span80为悬浮稳定剂,丙烯酸(AA)和丙烯酰胺(AM)为共聚单体,过硫酸钾为引发剂,N,N’-亚甲基双丙烯酰胺(NMBA)为交联剂,采用反相悬浮聚合法制备了聚(丙烯酸-丙烯酰胺)(PAA-AM)高吸水树脂,研究了丙烯酸中和度、单体配比、交联剂和引发剂的用量、反应温度等因素对树脂吸液性能的影响.结果表明,最佳条件下制备的树脂吸去离子水和0.9% NaCl水溶液的倍率分别为1282和109g/g.并且在同等条件下,该树脂样品与法国爱森(SNF)产同类产品相比具有较优异的吸水性能和耐盐性.

  5. Analysis and Testing of Bisphenol A—Free Bio-Based Tannin Epoxy-Acrylic Adhesives

    Directory of Open Access Journals (Sweden)

    Shayesteh Jahanshahi

    2016-04-01

    Full Text Available A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, 13C-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 °C for 12 h. FT-MIR, 13C-NMR and MALDI-TOF analysis have confirmed that the resin has been prepared under these conditions. The joints bonded with this resin were tested for block shear strength. The results obtained indicated that the best strength performance was obtained by the bioepoxy-acrylate adhesive resin prepared at 95 °C for a 12-h reaction.

  6. Constrained photophysics of partially and fully encapsulated charge transfer probe (E)-3-(4-Methylaminophenyl) acrylic acid methyl ester inside cyclodextrin nano-cavities: Evidence of cyclodextrins cavity dependent complex stoichiometry

    Science.gov (United States)

    Ghosh, Shalini; Jana, Sankar; Guchhait, Nikhil

    2011-12-01

    The polarity sensitive intra-molecular charge transfer (ICT) emission from (E)-3-(4-Methylaminophenyl) acrylic acid methyl ester (MAPAME) is found to show distinct changes once introduced into the nano-cavities of cyclodextrins in aqueous environment. Movement of the molecule from the more polar aqueous environment to the less polar, hydrophobic cyclodextrin interior is marked by the blue shift of the CT emission band with simultaneous fluorescence intensity enhancement. The emission spectral changes on complexation with the α- and β-CD show different stoichiometries as observed from the Benesi-Hildebrand plots. Fluorescence anisotropy and lifetime measurements were performed to probe the different behaviors of MAPAME in aqueous α- and β-CD solutions.

  7. FT-IR and FT-Raman studies of cross-linking processes with Ca2+ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - Part I

    Science.gov (United States)

    Grabowska, Beata; Sitarz, Maciej; Olejnik, Ewa; Kaczmarska, Karolina

    2015-01-01

    FT-IR and FT-Raman spectroscopic methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands. The cross-linking was performed by chemical methods by introducing cross-linking substances with Ca2+ ions or glutaraldehyde and by physical way, applying the microwave radiation. It was found that Ca2+ ions cause formation of cross-linking ionic bonds within carboxyl and carboxylate groups. Glutaraldehyde generates formation of cross-linking bonds with hemiacetal and acetal structures. Whereas in the microwave radiation field, due to dehydration, lattices are formed by anhydride bonds.

  8. 竹材加工剩余物耐盐性高吸水保水材料的制备及性能%Super absorbent resin from grafting acrylic acid onto bamboo fiber

    Institute of Scientific and Technical Information of China (English)

    曹玲燕; 赵稳祥; 虞小莹; 董聪勇; 金贞福

    2016-01-01

    竹材加工剩余物是丰富的可再生资源,且在培肥土壤、改善土壤微量元素等方面有积极作用。利用竹材加工剩余物制备高吸水保水材料,不仅使天然资源得到有效利用,还可以降低高吸水保水材料的成本,增加材料的复合功能。利用竹材加工剩余物为原材料,接枝丙烯酸、丙烯酰胺单体制备耐盐性高吸水性树脂。以过硫酸钾作为引发剂,通过将单体丙烯酸(AA)在一定条件下接枝到竹纤维上的共聚反应合成吸水性树脂,研究单体中和度、竹粉加入与否、引发剂用量、单体用量、碱液种类等对接枝共聚产物吸水树脂的吸水率的影响。碱液种类选取300.00 g·kg-1氢氧化钠水溶液、丙烯酸中和度为60.0%,引发剂用量为0.04 g,引发剂与单体丙烯酸同时加入、单体丙烯酸的用量为8.0 mL时吸水率高,达718.20 g·g-1。图1表4参12%This study was conducted to determine the effects of the degree of neutralization with acrylic acid, the quantity of initiator and acrylic acid to use, whether bamboo fiber should be added or not, and the alkalini-ty of the water for a super absorbent resin. The super absorbent resin was produced by grafting acrylic acid on-to bamboo fibers using potassium peroxodisulfate as an initiator. Results showed the optimum grafting condi-tions as the following: 60.0% monomer neutralization, 300.00 g·kg-1 alkalinity from a sodium hydroxide solu-tion, 0.04 g of potassium peroxodisulfate, and 8.0 mL acrylic acid. With optimum conditions the water absorp-tion was about 718.20 g·g-1.

  9. Industrial Application of the Catalyst for Oxidation of Prolylene to Acrylic Acid%丙烯氧化制丙烯酸催化剂在万吨级工业装置上的应用

    Institute of Scientific and Technical Information of China (English)

    李雪梅; 冯世强; 焦昆; 秦春华; 褚小东; 邵敬铭

    2012-01-01

    采用XRD和BET等手段对自制丙烯氧化制丙烯酸催化剂进行了表征;对该催化剂进行了小试、模试和10kt/a工业装置评价.试验结果表明,一段催化剂主要为CoMO4,Bi2M03O12,Bi2MoO6,FeMoO4,Co6Mo12Bi15Ox的晶相;二段催化剂主要为MoO3,Mo5Ol4,( Sb2O)M6O18( M=Mo,W,V)氧化物的晶相.小试评价结果为一段催化剂平均丙烯转化率98.1%、丙烯醛和丙烯酸总收率92.3%、氧化碳总收率3.4%,二段催化剂平均丙烯醛转化率99.7%、丙烯酸收率97.9%、氧化碳收率l.6%;一段和二段催化剂串联后,其模试评价的丙烯酸收率为88.8%,工业装置上运行时丙烯酸收率为88.9%.%The catalysts were characterized by means of XRD and BET, and their catalytic performance for oxidation of propylene to acrylic acid was evaluated through bench scale test, pilot scale test and 10 kt/a industrial test. The results showed that crystal phases of the first stage catalysts included CoMoO4, Bi2Mo3O12, Bi2MoO6, FeMoO4 and Co6Mo12Bi1.5Ox, and crystal phases of the second stage catalysts included MoO3, Mo5O14 and (Sb2O) M6O18(M=Mo, W, V). The bench scale test indicated 98.1% propylene conversion, 92.3% total yield of acrolein and acrylic acid, and 3.4% carbon oxide yield for the first stage catalyst, and 99.7% acrolein conversion, 97.9% acrylic acid yield and 1.6% carbon oxide yield for the second stage catalyst. The acrylic acid yield could reach 88.8% and 88.9% in the pilot scale test and the 10 kt/a industrial test, respectively.

  10. The influence of the partial pressure of air on the extent of surface and bulk grafting during the mutual irradiation of acrylic acid vapour and low-density polyethylene

    International Nuclear Information System (INIS)

    The influence of the partial pressure of air on the extent of grafting during the mutual irradiation (γ-ray) of acrylic acid vapour and low-density polyethylene films has been monitored by ESCA and infra-red spectroscopy. It was found that increasing the pressure at which the reaction tube was sealed from 8 x 10-5 to 2 x 10-4 Torr did not change the extent of bulk grafting but drastically reduced that on the surface, and gave rise to an embedded graft. The surface of the embedded graft is crosslinked. The degree of crosslinking also appears to be dependent on the partial pressure of air (i.e. oxygen). (author)

  11. 丙烯酸改性氯化聚丙烯的合成和粘接性能的研究%Study on synthesis and adhesiveness of modified chlorinated polypropylene with acrylic acid

    Institute of Scientific and Technical Information of China (English)

    傅和青; 黄洪; 张心亚; 陈焕钦

    2004-01-01

    氯化聚丙烯是聚丙烯的氯化改性产物,通过改性,其硬度、耐磨性、耐酸性、耐盐水性能比聚丙烯都好,耐热、耐老化性也优于聚丙烯.但其性能尤其是粘接性能还不能满足其在胶粘剂等方面的需要,为了进一步提高氯化聚丙烯的粘接性能,拓宽其应用领城,需对氯化聚丙烯改性.接枝共聚法是一种很好的化学改性方法.本文以丙烯酸(AA)作为接枝单体,以过氧化苯甲酰(BPO)为引发剂,以甲苯为溶剂,采用液相接枝共聚法,将丙烯酸单体接枝到氯化聚丙烯大分子链上,得到丙烯酸改性氯化聚丙烯产物.系统研究了反应温度、反应时间、引发剂过氧化苯甲酰用量和丙烯酸单体用量等因素对丙烯酸接枝改性的氯化聚丙烯产物粘接性能的影响,得出了较佳的工艺条件是反应温度T=100℃,反应时间t=3.5 h,原料质量配比为100份氯化聚丙烯、3份丙烯酸和0.3份的过氧化二苯甲酰.研究还表明,丙烯酸改性的氯化聚丙烯的粘接性能优于氯化聚丙烯的粘接性能.%Grafting of acrylic acid (AA) on chlorinated polypropylene (CPP) by free radical process was carried out at different temperatures and hours using toluene as solvent. The effect of temperature,time,initiator concentration and the ratio of chlorinated polypropylene and acrylic acid on the adhesiveness was studied. The optimum processing conditions were that the reaction temperature was 100 ℃, reaction time was 3.5 h,based on 100 parts chlorinated polypropylene 3 parts of acrylic acid and 0.30 parts benzoyl peroxide (BPO) were used. The adhesiveness of modified chlorinated polypropylene with acrylic acid was better than that of chlorinated polypropylene.

  12. [Treatment of acrylate wastewater by electrocatalytic reduction process].

    Science.gov (United States)

    Yu, Li-Na; Song, Yu-Dong; Zhou, Yue-Xi; Zhu, Shu-Quan; Zheng, Sheng-Zhi; Ll, Si-Min

    2011-10-01

    High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process. PMID:22279908

  13. 红外控温材料丙烯酸接枝石蜡的酰化研究%Study of Temperature Control Material Acylate of Paraffin Graft Acrylic Acid in Infrared Stealth Technology

    Institute of Scientific and Technical Information of China (English)

    孙翠玲; 徐国跃; 毛国强; 马文来

    2011-01-01

    The Acylation reaction of Paraffin graft Acrylic acid with aniline was carried out using the catalyst of Zn. The structure and the thermal property of the acylate were characterized by IR and DSC respectively. Modified paraffin's phase change temperature was widened by 16.3% successfully, and its latent heat was improved by 59.07% compared to paraffin. Of the three modified paraffins(paraffin-g-AA, paraffin-g-MMA, acylate of paraffin graft acrylic acid), acylate's phase change temperature/latent heat is the best. The relation of paraffin's phase change temperature/latent heat and its molecule structure was summarized.%以丙烯酸(AA)极性单体与石蜡接枝得到的丙烯酸接枝石蜡与酰胺反应生成酰化的接枝石蜡.用红外光谱仪和差示扫描量热仪对酰化的丙烯酸接枝石蜡的结构和热性能进行了分析.与未改性石蜡相比,酰化的丙烯酸接枝石蜡相变温度提高了16.3%,相变潜热提高了59.07%,在三种改性石蜡中酰化的丙烯酸接枝石蜡相变温度最高,相变潜热最大.分析三种改性石蜡的分子结构与其相变温度相变潜热的关系.

  14. ITX/EDAB光引发丙烯酸溶液聚合动力学%Kinetic study on the photoinitiated polymerization of acrylic acid initiated using isopropylthioxanthone/ethyl-4(dimethylamino)benzoate pair

    Institute of Scientific and Technical Information of China (English)

    李会玲; 杨万泰

    2001-01-01

    以异丙基硫杂蒽酮(ITX)/对-(二甲基氨基)苯甲酸乙酯(EDAB)为复配引发剂,研究了光引发丙烯酸溶液聚合动力学。结果表明,RP与单体浓度呈一次关系,引发剂反应级数在低浓度(<0.2 mmol/L)下为0.205 7,高浓度(>0.8 mmol/L)下为-0.1;反应速率存在最大值,此时引发剂浓度为0.8 mmol/L;聚合反应表观活化能为9.53 kJ/mol。%A kinetic study on the photo-induced polymerization of acrylic acid with ITX/EDAB as photo-initiator was carried out. The propagation reaction rate of acrylic acid was linear with monomer concentration. It was also found that the order of photo-initiator changed from 0.205 7 at low concentration(<0.2 mmol/L) to -0.1 at high concentration(>0.8 mmol/L). The maximum rate was obtained when the concentration of the initiator was 0.8 mmol/L. The apparant activation energy of polymerization was 9.53 kJ/mol.

  15. Simultaneous production of biobased styrene and acrylates using ethenolysis

    NARCIS (Netherlands)

    Spekreijse, J.; Notre, le J.E.L.; Haveren, van J.; Scott, E.L.; Sanders, J.P.M.

    2012-01-01

    Phenylalanine (1), which could be potentially obtained from biofuel waste streams, is a precursor of cinnamic acid (2) that can be converted into two bulk chemicals, styrene (3) and acrylic acid (4), via an atom efficient pathway. With 5 mol% of Hoveyda–Grubbs 2nd generation catalyst, 1 bar of ethyl

  16. [Acrylic resin removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de; Witter, D.J.; Creugers, N.H.J.

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

  17. Preparation and properties of UV curable acrylic PSA by vinyl bonded graphene oxide

    Science.gov (United States)

    Pang, Beili; Ryu, Chong-Min; Jin, Xin; Kim, Hyung-Il

    2013-11-01

    Acrylic pressure sensitive adhesives (PSAs) with higher thermal stability for thin wafer handling were successfully prepared by forming composite with the graphene oxide (GO) nanoparticles modified to have vinyl groups via subsequent reaction with isophorone diisocyanate and 2-hydroxyethyl methacrylate. The acrylic copolymer was synthesized as a base resin for PSAs by solution radical polymerization of ethyl acrylate, 2-ethylhexyl acrylate, and acrylic acid followed by further modification with GMA to have the vinyl groups available for UV curing. The peel strength of PSA decreased with the increase of gel content which was dependent on both modified GO content and UV dose. Thermal stability of UV-cured PSA was improved noticeably with increasing the modified GO content mainly due to the strong and extensive interfacial bonding formed between the acrylic copolymer matrix and GO fillers

  18. PREPARATION AND PROPERTIES OF THERMOSETTING ACRYLIC COATINGS USING TITANIUM-OXO-CLUSTER AS A CURING AGENT

    Institute of Scientific and Technical Information of China (English)

    Kun Xu; Shu-xue Zhou; Li-min Wu

    2009-01-01

    Thermosetting acrylic coatings were prepared by using carboxyl acid group-containing acrylic oligomer and curing with titanium-oxo-clusters which were first pre-hydrolyzed from titanium n-butoxide. The curing ability of the titanium-oxo-cluster was examined using a microdielectric analytical (DEA) curing monitor, Fourier transformed infrared spectroscopy (FTIR), and Soxhlet extraction experiments, and the properties of the resulted coatings were investigated with pendulum hardness tester, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and ultraviolet-visible spectrometer. The effect of titania-oxo-cluster in leading acrylic oligomers to form thermosetting acrylic coatings was confirmed. An increasing pendulum hardness and modulus of acrylic coatings with increasing titania content was observed, which resulted from the increment of crosslinking degree rather than of the titania content. The thermosetting acrylic/titania coatings also showed better thermal stability and higher UV-blocking properties than those coatings using organic curing agent.

  19. Epoxy-acrylic core-shell particles by seeded emulsion polymerization.

    Science.gov (United States)

    Chen, Liang; Hong, Liang; Lin, Jui-Ching; Meyers, Greg; Harris, Joseph; Radler, Michael

    2016-07-01

    We developed a novel method for synthesizing epoxy-acrylic hybrid latexes. We first prepared an aqueous dispersion of high molecular weight solid epoxy prepolymers using a mechanical dispersion process at elevated temperatures, and we subsequently used the epoxy dispersion as a seed in the emulsion polymerization of acrylic monomers comprising methyl methacrylate (MMA) and methacrylic acid (MAA). Advanced analytical techniques, such as scanning transmission X-ray microscopy (STXM) and peak force tapping atomic force microscopy (PFT-AFM), have elucidated a unique core-shell morphology of the epoxy-acrylic hybrid particles. Moreover, the formation of the core-shell morphology in the seeded emulsion polymerization process is primarily attributed to kinetic trapping of the acrylic phase at the exterior of the epoxy particles. By this new method, we are able to design the epoxy and acrylic polymers in two separate steps, and we can potentially synthesize epoxy-acrylic hybrid latexes with a broad range of compositions.

  20. Advances in acrylic-alkyd hybrid synthesis and characterization

    Science.gov (United States)

    Dziczkowski, Jamie

    2008-10-01

    In situ graft acrylic-alkyd hybrid resins were formed by polymerizing acrylic and acrylic-mixed monomers in the presence of alkyds by introduction of a free radical initiator to promote graft formation. Two-dimensional NMR, specifically gradient heteronuclear multiple quantum coherence (gHMQC), was used to clarify specific graft sites of the hybrid materials. Both individual and mixed-monomer systems were produced to determine any individual monomer preferences and to model current acrylic-alkyd systems. Different classes of initiators were used to determine any initiator effects on graft location. The 2D-NMR results confirm grafting at doubly allylic hydrogens located on the fatty acid chains and the polyol segment of the alkyd backbone. The gHMQC spectra show no evidence of grafting across double bonds on either pendant fatty acid groups or THPA unsaturation sites for any of the monomer or mixed monomer systems. It was also determined that choice of initiator has no effect on graft location. In addition, a design of experiments using response surface methodology was utilized to obtain a better understanding of this commercially available class of materials and relate both the chemical and physical properties to one another. A Box-Behnkin design was used, varying the oil length of the alkyd phase, the degree of unsaturation in the polyester backbone, and acrylic to alkyd ratio. Acrylic-alkyd hybrid resins were reduced with an amine/water mixture. Hydrolytic stability was tested and viscoelastic properties were obtained to determine crosslink density. Cured films were prepared and basic coatings properties were evaluated. It was found that the oil length of the alkyd is the most dominant factor for final coatings properties of the resins. Acrylic to alkyd ratio mainly influences the resin properties such as acid number, average molecular weight, and hydrolytic stability. The degree of unsaturation in the alkyd backbone has minimal effects on resin and film

  1. The use of epoxidised palm oil products (EPOP) for the synthesis of radiation curable resins 1. Synthesis of epoxidised RBD palm olein acrylate

    International Nuclear Information System (INIS)

    The synthesis of acrylated olein utilizing epoxidised refined, bleached and deodorized (RBD) palm olein has been carried out by acrylation reaction. This is done by the introduction of acrylic acid into oxirane group of the epoxidised RBD palm olein. The reaction was confirmed by analytical data i.e. oxirane oxygen content, iodine value and acid value and IR spectrophotometric method. It was found that, oxirane group in triglyceride molecule of epoxidised RBD palm olein (EPOL) is attacked by acrylic acid to yield epoxidised RBD palm olein acrylate (EPOLA). The EPOLA was found curable when subjected to ultraviolet radiation

  2. Adsorption mechanism and dispersion efficiency of three anionic additives [poly(acrylic acid), poly(styrene sulfonate) and HEDP] on zinc oxide.

    Science.gov (United States)

    Dange, C; Phan, T N T; André, V; Rieger, J; Persello, J; Foissy, A

    2007-11-01

    Adsorption on ZnO of sodium poly(acrylate) (PAA), sodium poly(styrene sulfonate) (PSS) and a monomer surfactant [hydroxyethylidene diphosphonate (HEDP)] was investigated in suspensions initially equilibrated at pH 7. Results demonstrate interplay in the adsorption mechanism between zinc complexation, salt precipitation, and ZnO dissolution. In the case of PAA, the adsorption isotherm exhibits a maximum attributed to the precipitation of zinc polyacrylate. PSS and HEDP formed high-affinity adsorption isotherms, but the plateau adsorption of HEDP was significantly lower than that of PSS. The adsorption isotherm of each additive is divided into two areas. At low additive concentration (high zinc/additive ratio), the total zinc concentration in the solution decreased and the pH increased upon addition. At a higher additive ratio, zinc concentration and pH increased with the organic concentration. The increase in pH is due to the displacement of hydroxyl ions from the surface and the increase in zinc concentration results from the dissolution of ZnO due to the complexation of zinc ions by the organics. The stability of the ZnO dispersions was investigated by measurement of the particle size distribution after addition of various amounts of polymers. The three additives stabilized the ZnO dispersions efficiently once full surface coverage was reached. PMID:17720181

  3. Synthesis of Radiation Curable Palm Oil–Based Epoxy Acrylate: NMR and FTIR Spectroscopic Investigations

    Directory of Open Access Journals (Sweden)

    Ashraf M. Salih

    2015-08-01

    Full Text Available Over the past few decades, there has been an increasing demand for bio-based polymers and resins in industrial applications, due to their potential lower cost and environmental impact compared with petroleum-based counterparts. The present research concerns the synthesis of epoxidized palm oil acrylate (EPOLA from an epoxidized palm oil product (EPOP as environmentally friendly material. EPOP was acrylated by acrylic acid via a ring opening reaction. The kinetics of the acrylation reaction were monitored throughout the reaction course and the acid value of the reaction mixture reached 10 mg KOH/g after 16 h, indicating the consumption of the acrylic acid. The obtained epoxy acrylate was investigated intensively by means of FTIR and NMR spectroscopy, and the results revealed that the ring opening reaction was completed successfully with an acrylation yield about 82%. The UV free radical polymerization of EPOLA was carried out using two types of photoinitiators. The radiation curing behavior was determined by following the conversion of the acrylate groups. The cross-linking density and the hardness of the cured EPOLA films were measured to evaluate the effect of the photoinitiator on the solid film characteristics, besides, the thermal and mechanical properties were also evaluated.

  4. Synthesis and Characterization of Chitosan Oligosaccharide-graft-Acrylic Acid Biodegradable Crosslinker%丙烯酸接枝壳寡糖生物可降解交联剂的合成与表征

    Institute of Scientific and Technical Information of China (English)

    苏宇佳; 赵骞; 孙建中

    2012-01-01

    在1-乙基-3-(3-二甲氨丙基)碳化二亚胺盐酸盐(EDC)和N-羟基琥珀酰亚胺(NHS)催化作用下,采用水溶性的壳寡糖(CSO)与丙烯酸(AA)发生N-酰化反应,制备出一种新型水溶性可降解水凝胶交联剂——丙烯酸接枝壳寡糖(CSO-g-AA).用CSO-g-AA与丙烯酰胺单体共聚制备了聚丙烯酰胺水凝胶.该水凝胶可在蜗牛酶作用下降解为水溶性直链聚丙烯酰胺.采用1H-NMR、红外吸收光谱法对CSO-g-AA结构进行表征,用溴酸钾-溴化钾滴定法定量分析了CSO-g-AA中不饱和双键的含量.结果表明:该交联剂中不饱和双键的接枝率约为4%,在适当的温度、pH值和酶浓度下水凝胶经72 h完全降解.%A new water soluble and biodegradable crosslinker of chitosan oligosaccharide-graft-acrylic acid (CSO-g-AA) was synthesized through the acrylyl reaction of amino groups in the chitosan oligosaccharide (CSO) chains with acrylic acid (AA) catalyzed by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimidehydro-chloride (EDC) and N-hydroxysuccinimide (NHS). Polyacrylamide (PAM) hydrogels were prepared by copolymerization of acrylamide and CSO-g-AA. CSO-g-AA was structurally characterized by Fourier transform infrared spectroscopy (FT-IR) and H-1 nuclear magnetic resonance (1H-NMR) spectroscopy. The content of unsaturated double bond in CSO-g-AA was quantitatively analysed by titration analysis using potassium bromate (KBrO) and potassium bromide (KBr). The results show that the grafting ratio of unsaturated double bond in CSO-g-AA is about 4%. At a proper temperature, pH value and concentration of enzyme, the PAM hydrogels can be degraded to water soluble polyacrylamide chains in 72 h under the catalysis of snailase.

  5. 壳聚糖钯配合物磁微球的合成及其在催化丙烯酸与碘代苯反应中的性能%Synthesis of a magnetic-separated chitosan-palladium complex and its catalytic activity in the reaction of acrylic acid with iodobenzene

    Institute of Scientific and Technical Information of China (English)

    杨黎明; 张群飞; 陈捷; 曹芳琦; 戎亮; 曹春燕

    2008-01-01

    A magnetic-separated catalyst of chitosan-palladium complex (Fe3O4-CS-Pd) based on chitosan coated Fe3O4 microspheres was prepared by the "bottom-up" approach. The catalytic behavior of the catalyst in the cross coupling reaction of acrylic acid (AA) with iodobenzene (ArI) was investigated. Compared with the traditional homogeneous palladium catalysts, the catalyst was easily separated and reused.

  6. SYNTHESIS OF ACRYLIC ESTERS IN PTC: KINETICS AND ECOLOGICAL ASPECTS

    Directory of Open Access Journals (Sweden)

    G.Torosyan

    2013-06-01

    Full Text Available The synthesis of esters of acrylic acids, which are applied for synthesis of polymeric materials by phase transfer catalysis were discussed (PTC, which is very useful for reduction of reaction consumption of materials and power.This method has substantial advantages including high speed of the process, soft condition of reaction and reduced pollution.

  7. (Liquid + liquid) equilibria in {l_brace}water + acrylic acid + (1-butanol, or 2-butanol, or 1-pentanol){r_brace} systems at T = 293.2 K, T = 303.2 K, and T = 313.2 K and atmospheric pressure

    Energy Technology Data Exchange (ETDEWEB)

    Batistell, Melissa C.; Alves, Thiago C.; Guadagnini, Talita R.; Hadlich de Oliveira, Leonardo [School of Chemical Engineering, University of Campinas, Av. Albert Einstein 500, 13083-852 Campinas-SP (Brazil); Aznar, Martin, E-mail: maznar@feq.unicamp.br [School of Chemical Engineering, University of Campinas, Av. Albert Einstein 500, 13083-852 Campinas-SP (Brazil)

    2011-09-15

    Highlights: > Acrylic acid solubilizes preferably in the studied solvents than in water. > Immiscibility region increases in the order: 2-butanol < 1-butanol < 1-pentanol. > Immiscibility region reduces little with an increase in temperature. > K and S values show that 1-pentanol is the best studied solvent. - Abstract: (Liquid + liquid) equilibrium (LLE) data for {l_brace}water + acrylic acid + (1-butanol, or 2-butanol, or 1-pentanol){r_brace} at T = 293.2 K, T = 303.2 K, and T = 313.2 K and atmospheric pressure ({approx}95 kPa) were determined by Karl Fischer titration and densimetry. All systems present type I binodal curves. The size of immiscibility region changes little with an increase in temperature, but increases according to the solvent, following the order: 2-butanol < 1-butanol < 1-pentanol. Values of solute distribution and solvent selectivities show that 1-pentanol is a better solvent than 1-butanol or 2-butanol for acrylic acid removal from water solutions. Quality of data was ascertain by Hand and Othmer-Tobias equations, giving R{sup 2} > 0.916, mass balance and accordance between tie lines and cloud points. The NRTL model was used to correlate experimental data, by estimating new energy parameters, with root mean square deviations below 0.0053 for all systems.

  8. Selective surface functionalization of polystyrene induced by synchrotron or UV radiation in the presence of oxygen or acrylic acid vapors; Funcionalizacao superficial seletiva de poliestireno induzida por radiacao sincrotron ou ultravioleta

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, Felipe; Kuhn, Sidiney; Weibel, Daniel E., E-mail: felipekessler@gmail.co [Universidade Federal do Rio Grande do Sul (IQ/UFRGS), Porto Alegre, RS (Brazil) Inst. de Quimica. Dept. de Fisico-Quimica

    2009-07-01

    Efficient surface functionalization of Polystyrene (PS) thin films by electromagnetic radiation in combination with a reactive gaseous atmosphere was obtained. Monochromatic synchrotron (SR) or polychromatic UV radiation were used as excitation sources. When SR was used, O{sub 2} was introduced after irradiation into the UHV chamber. UV irradiation was carried out keeping a constant flow of O{sub 2} or acrylic acid (AA) vapors during the photolysis. FTIR-ATR and XPS-NEXAFS spectra were obtained at the UFRGS and the LNLS, Campinas respectively. PS films were functionalized by monochromatic SR and then expose to O{sub 2} at specific transitions such us C 1s {yields}{sigma}{sup *}{sub C-C} excitation. It was found a high rate of COO, C=O and C-O groups at the surface (> 70%). UV-assisted treatment in the presence of AA vapors showed that an efficient polymerization process took place, such as, it was observed in previous AA low pressure RF plasma treatments. UV-assisted functionalization has the advantage of lower costs and simple set-up compared to plasma treatments. (author)

  9. Preparation of Uniform-Sized and Dual Stimuli-Responsive Microspheres of Poly(N-Isopropylacrylamide/Poly(Acrylic acid with Semi-IPN Structure by One-Step Method

    Directory of Open Access Journals (Sweden)

    En-Ping Lai

    2016-03-01

    Full Text Available A novel strategy was developed to synthesize uniform semi-interpenetrating polymer network (semi-IPN microspheres by premix membrane emulsification combined with one-step polymerization. Synthesized poly(acrylic acid (PAAc polymer chains were added prior to the inner water phase, which contained N-isopropylacrylamide (NIPAM monomer, N,N′-methylene bisacrylamide (MBA cross-linker, and ammonium persulfate (APS initiator. The mixtures were pressed through a microporous membrane to form a uniform water-in-oil emulsion. By crosslinking the NIPAM in a PAAc-containing solution, microspheres with temperature- and pH-responsive properties were fabricated. The semi-IPN structure and morphology of the microspheres were confirmed by Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. The average diameter of the obtained microspheres was approximately 6.5 μm, with Span values of less than 1. Stimuli-responsive behaviors of the microspheres were studied by the cloud-point method. The results demonstrated that semi-IPN microspheres could respond independently to both pH and temperature changes. After storing in a PBS solution (pH 7.0 at 4 °C for 6 months, the semi-IPN microspheres remained stable without a change in morphology or particle size. This study demonstrated a promising method for controlling the synthesis of semi-IPN structure microspheres with a uniform size and multiple functionalities.

  10. Cyto- and genotoxicological assessment and functional characterization of N-vinyl-2-pyrrolidone-acrylic acid-based copolymeric hydrogels with potential for future use in wound healing applications

    Energy Technology Data Exchange (ETDEWEB)

    Kirf, Dominik; Devery, Sinead M [Department of Life and Physical Science, Athlone Institute of Technology (Ireland); Higginbotham, Clement L [Materials Research Institute, Athlone Institute of Technology (Ireland); Rowan, Neil J, E-mail: sdevery@ait.i, E-mail: dkirf@ait.i, E-mail: chigginbotham@ait.i, E-mail: nrowan@ait.i [Department of Nursing and Health Science, Athlone Institute of Technology (Ireland)

    2010-06-01

    This study investigated the toxicity of N-vinyl-2-pyrrolidone-acrylic acid copolymer hydrogels crosslinked with ethylene glycol dimethacrylate or poly(ethylene glycol) dimethacrylate. There is a pressing need to establish the toxicity status of these new copolymers because they may find applications in future wound healing processes. Investigations revealed that the capacity of these hydrogels for swelling permitted the retention of high amounts of water yet still maintaining structural integrity. Reverse phase HPLC analysis suggested that unreacted monomeric base material was efficiently removed post-polymerization by applying an additional purification process. Subsequently, in vitro toxicity testing was performed utilizing direct and indirect contact exposure of the polymers to human keratinocytes (HaCaT) and human hepatoma (HepG2) cells. No indication of significant cell death was observed using the established MTT, neutral red (NR) and fluorescence-based toxicity endpoint indicators. In addition, the alkaline Comet assay showed no genotoxic effects following cell exposure to hydrogel extracts. Investigations at the nucleotide level using the Ames mutagenicity assay demonstrated no evidence of mutagenic activity associated with the polymers. Findings from this study demonstrated that these hydrogels are non-cytotoxic and further work can be carried out to investigate their potential as a wound-healing device that will impact positively on patient health and well-being.

  11. Synthesis and application in acrylic rubber of 2-butoxyethanol esters of hexanedioic acid%己二酸-乙二醇单丁醚酯的合成及在丙烯酸酯橡胶中的应用

    Institute of Scientific and Technical Information of China (English)

    宋林勇; 贺楠楠; 周艺峰; 聂王焰

    2011-01-01

    用对甲苯磺酸作催化剂,以己二酸与乙二醇单丁醚为原料,通过酯化反应合成了己二酸-乙二醇单丁醚酯增塑剂,考察了反应时间、醇酸摩尔比及催化剂和带水剂甲苯的用量对酯化反应的影响,通过傅里叶变换红外光谱及核磁共振氢谱对产物进行了表征,并研究了该增塑剂在丙烯酸酯橡胶中的高低温增塑性能.结果表明,酯化反应的最佳反应条件为反应时间180 min、醇酸摩尔比2.5、催化剂和带水剂的质量分数分别是醇与酸总用量的0.5%和30%;添加10份该增塑剂可使丙烯酸酯橡胶的脆化温度达到-35.0℃,且在150℃下能保持较好的物理机械性能.%Plasticizer, 2-butoxyethanol ester of hexanedioic acid, was synthesized by esterification of hexanedioic acid and 2-butoxyethanol with toluene sulfonic acid as catalyst, the effects of reaction time ,mole ratio of alcohol to acid and level of catalyst and water-carrying agent toluene on the esterification were investigated, the synthesized products was characterized by Fourier transform-infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, and the high and low temperature plasticizing ability was studied in detail. The results showed that the optimal condition for esterification was as follows : reaction time 180 min , mole ratio of alcohol to acid 2. 5, mass fraction of catalyst and water-carrying agent in total amount of alcohol and acid 0. 5% and 30% respectively. The brittlness temperature of acrylic rubber could reach -35℃ when the amount of the plasticizer was 10 phr, and the mechanical property was kept well at 150 ℃ .

  12. Biocatalytic functionalization of hydroxyalkyl acrylates and phenoxyethanol via phosphorylation.

    Science.gov (United States)

    Tasnádi, Gábor; Hall, Mélanie; Baldenius, Kai; Ditrich, Klaus; Faber, Kurt

    2016-09-10

    The enzymatic phosphorylation of phenoxyethanol, 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate catalyzed by acid phosphatases PhoN-Sf and PiACP at the expense of inorganic di-, tri-, hexameta- or polyphosphate was applied to the preparative-scale synthesis of phosphorylated compounds. The reaction conditions were optimized with respect to enzyme immobilization, substrate concentration, pH and type of phosphate donor. The mild reaction conditions prevented undesired polymerization and hydrolysis of the acrylate ester moiety. Application of a continuous flow system allowed facile scale-up and mono-phosphates were obtained in up to 26% isolated yield with space-time yields of 0.89kgL(-1)h(-1). PMID:27422352

  13. Synthesis and Demulsibility of the Terpolymer Demulsifier of Acryl Resin

    Institute of Scientific and Technical Information of China (English)

    KANG,Wan-Li; MENG,Ling-Wei; ZHANG,Hong-Yan; LIU,Shu-Ren

    2008-01-01

    Terpolymer demulsifier of acryl resin has been synthesized through solution polymerization with water as a dissolvent,potassium persulfate as an initiator and the monomers of methyl methacrylate,butyl acrylate and acrylic acid as starting materials.The effects of the reaction temperature,dripping time,the amount of monomers and initiator on the dehydration rate of the demulsifier were investigated by an orthogonal experiment.It shows that the stronger influence on the dehydration rate among six factors is reaction temperature,dripping time,and amount of catalyst,while monomer has weak influence.The performance of the demulsifier was evaluated under different demulsification time,temperatures and concentrations of the screened demulsifiers.The result shows that the dehydration rate of the demulsifier can reach over 67%,which is better than that by the emulsion polymerization way.

  14. SORPTION OF Cu(II) BY POLY(HYDROXAMIC ACID) CHELATING EXCHANGER PREPARED FROM POL(YMETHYL ACRYLATE) GRAFTED OIL PALM EMPTY FRUIT BUNCH (OPEFB)

    OpenAIRE

    Md Jelas Haron; Mariati Tiansih; Nor Azowa Ibrahim; Anuar Kassim; W. M. Z. Wan Yunus

    2009-01-01

    This paper describes the preparation of chemically modified oil palm empty fruit bunch (OPEFB) with hydroxamic acid functional group and its use for the sorption of Cu(II) from aqueous solution. OPEFB was grafted with poly(methylacrylate) (PMA), using H2O2/Fe2+ as initiator. The PMA grafted OPEFB (PMA-OPEFB) was treated with hydroxylammonium chloride in alkaline medium to produce hydroxamic acid grafted fiber (PHA-OPEFB). The FTIR spectrum of OPEFB grafted with PMA showed an intense absorpt...

  15. Mutagenicity assessment of acrylate and methacrylate compounds and implications for regulatory toxicology requirements.

    Science.gov (United States)

    Johannsen, F R; Vogt, Barbara; Waite, Maureen; Deskin, Randy

    2008-04-01

    Esters of acrylic acid and methacrylic acid, more commonly known as acrylates and methacrylates, respectively, are key raw materials in the coatings and printing industry, with several of its chemical class used in food packaging. The results of over 200 short-term in vitro and in vivo mutagenicity studies available in the open literature have been evaluated. Despite differences in acrylate or methacrylate functionality or in the number of functional groups, a consistent pattern of test response was seen in a typical regulatory battery of mutagenicity tests. No evidence of point mutations was observed when acrylic acid or over 60 acrylates and methacrylates were investigated in Salmonella bacterial tests or in hprt mutation tests mammalian cells, and no evidence of a mutagenic effect was seen when tested in whole animal clastogenicity and/or aneuploidy (chromosomal aberration/micronucleus) studies. Consistent with the in vivo testing results, acrylic acid exhibited no evidence of carcinogenicity in chronic rodent cancer bioassays. In contrast, acrylic acid and the entire acrylate and methacrylate chemical class produced a consistently positive response when tested in the mouse lymphoma assay and/or other in vitro mammalian cell assays designed to detect clastogenicity. The biological relevance of this in vitro response is questioned based on the non-concordance of in vitro results with those of in vivo studies addressing the same mutagenic endpoint (clastogenicity). Thus, in short-term mutagenicity tests, the acrylates and methacrylates behave as a single chemical category, and genotoxicity behavior of a similar chemical can be predicted with confidence by inclusion within this chemical class, thus avoiding unnecessary testing. PMID:18346829

  16. Synthesis, Characterization, and Aqueous Lubricating Properties of Amphiphilic Graft Copolymers Comprising 2-Methoxyethyl Acrylate

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Røn, Troels; Jankova Atanasova, Katja;

    2014-01-01

    reversible addition–fragmentation chain transfer (RAFT) polymerization, copper-mediated atom transfer radical polymerization (ATRP), and a selective deprotection reaction. Initially, multifunctional ATRP macroinitiators based on PHEMA backbone are prepared by RAFT polymerization. Then ATRP......Amphiphilic anionic and cationic graft copolymers possessing poly(2-hydroxyethyl methacrylate) (PHEMA) backbone and poly(methacrylic acid), poly(2-methoxyethyl acrylate-co-methacrylic acid), and poly(2-methoxyethyl acrylate-co-2-(dimethylamino)ethyl methacrylate) grafts are constructed by merging...

  17. Using NMR chemical shift imaging to monitor swelling and molecular transport in drug-loaded tablets of hydrophobically modified poly(acrylic acid): methodology and effects of polymer (in)solubility.

    Science.gov (United States)

    Knöös, Patrik; Topgaard, Daniel; Wahlgren, Marie; Ulvenlund, Stefan; Piculell, Lennart

    2013-11-12

    A new technique has been developed using NMR chemical shift imaging (CSI) to monitor water penetration and molecular transport in initially dry polymer tablets that also contain small low-molecular weight compounds to be released from the tablets. Concentration profiles of components contained in the swelling tablets could be extracted via the intensities and chemical shift changes of peaks corresponding to protons of the components. The studied tablets contained hydrophobically modified poly(acrylic acid) (HMPAA) as the polymer component and griseofulvin and ethanol as hydrophobic and hydrophilic, respectively, low-molecular weight model compounds. The water solubility of HMPAA could be altered by titration with NaOH. In the pure acid form, HMPAA tablets only underwent a finite swelling until the maximum water content of the polymer-rich phase, as confirmed by independent phase studies, had been reached. By contrast, after partial neutralization with NaOH, the polyacid became fully miscible with water. The solubility of the polymer affected the water penetration, the polymer release, and the releases of both ethanol and griseofulvin. The detailed NMR CSI concentration profiles obtained highlighted the clear differences in the disintegration/dissolution/release behavior for the two types of tablet and provided insights into their molecular origin. The study illustrates the potential of the NMR CSI technique to give information of importance for the development of pharmaceutical tablets and, more broadly, for the general understanding of any operation that involves the immersion and ultimate disintegration of a dry polymer matrix in a solvent. PMID:24106807

  18. Bonding auto-polymerising acrylic resin to acrylic denture teeth.

    LENUS (Irish Health Repository)

    Nagle, Susan

    2009-09-01

    This study investigated the effect of surface treatments on the shear bond strength of an auto-polymerising acrylic resin cured to acrylic denture teeth. The surface treatments included a combination of grit-blasting and\\/or wetting the surface with monomer. Samples were prepared and then stored in water prior to shear testing. The results indicated that the application of monomer to the surface prior to bonding did not influence the bond strength. Grit blasting was found to significantly increase the bond strength.

  19. SORPTION OF Cu(II BY POLY(HYDROXAMIC ACID CHELATING EXCHANGER PREPARED FROM POL(YMETHYL ACRYLATE GRAFTED OIL PALM EMPTY FRUIT BUNCH (OPEFB

    Directory of Open Access Journals (Sweden)

    Md Jelas Haron

    2009-11-01

    Full Text Available This paper describes the preparation of chemically modified oil palm empty fruit bunch (OPEFB with hydroxamic acid functional group and its use for the sorption of Cu(II from aqueous solution. OPEFB was grafted with poly(methylacrylate (PMA, using H2O2/Fe2+ as initiator. The PMA grafted OPEFB (PMA-OPEFB was treated with hydroxylammonium chloride in alkaline medium to produce hydroxamic acid grafted fiber (PHA-OPEFB. The FTIR spectrum of OPEFB grafted with PMA showed an intense absorption band at 1734 cm-1 which is attributed to C=O vibration in the grafted ester. After hydroxylamine treatment, the intensity of absorption band at 1734 cm-1 decreased and new bands appeared at the 1640 cm-1 related to C=O vibration in hydroxamic acid and at the 1568 cm-1 related to the N-H amide. Sorption of Cu(II by PHA-OPEFB was effective over a pH range of 4 to 6. The sorption followed the Langmuir model with maximum capacities of 74.1 mg g-1 at 25 °C. The sorption process was exothermic, as shown by the negative value of enthalpy change, H. The free energy change (G for the sorption was negative, showing that the sorption process was spontaneous. A kinetic study showed that the Cu(II sorption followed a second order kinetic model.

  20. 粉体辐射接枝丙烯酸的聚偏氟乙烯超滤膜的制备%Preparation of PVDF-graft-poly(acrylic acid) UF Membranes

    Institute of Scientific and Technical Information of China (English)

    卞晓锴; 施柳青; 于洋; 邓波; 李景烨; 陆晓峰

    2012-01-01

    PVDF-graft-poly (acrylic acid) (PVDF-g-PAA) was used as the material to prepare UF membrane via the phase inversion method. The solubility parameter of PVDF-g-PAA was tested. The effects of the type of solvents, polymer concentration, additives concentration, as well as the temperature of coagulation bath on the performance and structure of the PVDF-g-PAA membranes were discussed. The results showed that after being grafted with acrylic acid, the solubility parameter of PVDF-g-PAA was increased and the polarity of this polymer was enhanced. When DMF or NMP was used as solvent in the preparation of UF membranes, the membrane had a denser skin layer, a lower water flux and a higher rejection of BSA; when DMSO was used as solvent, there were some larger pores distributed on the membrane surface layer, and the membrane had the highest water flux and the lowest rejection of BSA; with the increase in the polymer concentration, the membrane structure became denser, the water flux decreased and the rejection of BSA increased; the increase in PEG400 concentration would lead to an increase in membrane flux and a more porous surface layer. Moreover, the thickness of the membranes also increased, and the starting position of macrovoids shifted further into the membranes; within the temperature range of 12-23 ℃ , with the increase in temperature, the flux of the membrane increased, and the rejection of BSA decreased.%采用粉体辐射接枝丙烯酸的聚偏氟乙烯( PVDF-g - PAA)为材料,以浸没沉淀相转化法制备PVDF- g- PAA超滤膜,研究了接枝后材料溶解性能的变化、以及溶剂种类、聚合物浓度、添加剂种类及浓度、凝胶浴温度制膜参数对PVDF- g- PAA膜结构及性能的影响.结果表明:辐射接枝丙烯酸后,聚合物的溶度参数增大,同时聚合物的极性也增强.在溶剂影响的考察中,以二甲基甲酰胺(DMF)和N-甲基吡咯烷酮(NMP)为溶剂制备的PVDF-g-PAA膜表面致密,透

  1. Technology and the use of acrylics for provisional dentine protection.

    Science.gov (United States)

    Kapusevska, Biljana; Dereban, Nikola; Popovska, Mirjana; Nikolovska, Julijana; Radojkova Nikolovska, Vеrа; Zabokova Bilbilova, Efka; Mijoska, Aneta

    2013-01-01

    Acrylics are compounds polymerized from monomers of acrylic, metacrylic acid or acrylonitrates. The purpose of this paper is to present the technology and use of acrylics for provisional dentine protection in the practice of dental prosthodontics. For this reason, we followed 120 clinical cases from the everyday clinical practice, divided into 4 groups of 30 patients who needed prosthetic reconstruction. The first group included cases in which we applied celluloid crowns for dentine protection, for the second group we used acrylic teeth from a set of teeth for complete dentures; in the third and fourth groups the fabrication was done with the system of an impression matrix and the acrylic resin block technique respectively. In all the examined patients, the gingival index by Silness and Loe and the vitality of the dental pulp were verified clinically, after preparation and 8 days from the placement of the provisional crown. The value for dental sensitivity measured after preparation was 2.59, and 8 days after the placement of the provisional crown it bwas 3.1. From these results we can conclude that after the 8th day from the placement of the provisional crown, there was an adaptation period, characterized by a decrease in the painful sensations. The value of the Silness and Loe gingival index measured after the preparation was 1.34, and 8 days from the placement of the provisional crown was 0.94. The results inclined us to the fact that the provisional acrylic crowns facilitated the reparation of the periodontal tissue. PMID:24566021

  2. Evaluation of the antifouling and photocatalytic properties of poly(vinylidene fluoride) plasma-grafted poly(acrylic acid) membrane with self-assembled TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    You, Sheng-Jie, E-mail: sjyou@cycu.edu.tw [Department of Bioenvironmental Engineering, Chung Yuan Christian University, Chungli, Taiwan (China); R and D Center for Membrane Technology, Chung Yuan Christian University, Chungli, Taiwan (China); Semblante, Galilee Uy [Department of Bioenvironmental Engineering, Chung Yuan Christian University, Chungli, Taiwan (China); R and D Center for Membrane Technology, Chung Yuan Christian University, Chungli, Taiwan (China); Lu, Shao-Chung [Department of Civil Engineering, Chung Yuan Christian University, Chungli, Taiwan (China); Damodar, Rahul A. [Department of Bioenvironmental Engineering, Chung Yuan Christian University, Chungli, Taiwan (China); R and D Center for Membrane Technology, Chung Yuan Christian University, Chungli, Taiwan (China); Wei, Ta-Chin [R and D Center for Membrane Technology, Chung Yuan Christian University, Chungli, Taiwan (China); Department of Chemical Engineering, Chung Yuan Christian University, Chungli, Taiwan (China)

    2012-10-30

    Highlights: Black-Right-Pointing-Pointer Plasma and grafting parameters that maximized TiO{sub 2} binding sites were found. Black-Right-Pointing-Pointer PVDF hydrophilicity was vastly improved compared to other modification techniques. Black-Right-Pointing-Pointer At least 1.5% TiO{sub 2} and 30 min UV exposure were needed to attain full flux recovery. Black-Right-Pointing-Pointer Photocatalytic membranes could remove up to 42% of 50 mg/l RB5 dye. - Abstract: Immobilization of TiO{sub 2} is a promising approach that produces antifouling and photocatalytic membranes that could help advance wastewater treatment and re-use processes. In this study, poly(acrylic acid) (PAA) was plasma-grafted on commercial poly(vinylidene fluoride) (PVDF) to introduce functional groups on the membrane surface that can support the nanoparticles. It was found that plasma treatment at 100 W for 120 s followed by liquid grafting with 70% aqueous AA at 60 Degree-Sign C for 2 h maximized the number of TiO{sub 2} binding sites. Membrane hydrophilicity was tremendously enhanced by the self-assembly of TiO{sub 2}, following a direct proportionality to TiO{sub 2} loading. The membrane with 0.5% TiO{sub 2} loading maintained the highest pure water flux and the best protein antifouling property. UV irradiation triggered the photodegradation of strongly bound foulants, but at least 1.5% TiO{sub 2} and 30 min cumulative irradiation were necessary to completely recover the membrane's original performance. The TiO{sub 2}-modified membranes removed 30-42% of 50 mg/l aqueous Reactive Black 5 (RB5) dye. The fabricated membranes demonstrate huge potential for use in membrane reactors with high hydrophilicity, fouling mitigation, and photocatalytic capability.

  3. The use of superporous p(AAc (acrylic acid)) cryogels as support for Co and Ni nanoparticle preparation and as reactor in H2 production from sodium borohydride hydrolysis

    International Nuclear Information System (INIS)

    Here, we report for the first time the use of p(AAc (p(acrylic acid)) cryogel for in situ metal nanoparticle preparation, and their use as a superporous reactor for H2 generation from hydrolysis of NaBH4. Superporous p(AAc) cryogels and conventional hydrogels were prepared via free radical polymerization technique at low (−18 °C) and moderate (40 °C) temperatures, respectively. They were characterized by employing various methods such as swelling experiments, optical imaging, and SEM (Scanning Electron Microscopy) analysis. By reducing Co2+ and Ni2+ ions within p(AAc) cryogel and hydrogel matrices, the obtained Co and Ni metal nanoparticles were employed for H2 generation from NaBH4 hydrolysis. Various factors such as porosity, metal type, temperature, and the amount of sodium hydroxide were investigated to determine their effects on hydrogen generation from NaBH4 hydrolysis. Activation energy (Ea), enthalpy (ΔH#) and entropy (ΔS#) for NaBH4 hydrolysis by superporous p(AAc)-Co metal composites were 29.35 kJ mol−1,=36.85 kJ mol−1, and –157.88 J mol−1K−1, respectively. Cryogels showed better catalytic activity than conventional hydrogels in the hydrolysis reaction, and have a higher TOF (turnover frequency) value of 4.10 mol H2 (mol catalyst min)−1 compared to conventional hydrogels, due to its highly porous nature, short diffusion distances and fast response times. - Highlights: • Superporous cryogel supports for in situ metal nanoparticle preparation. • Fast H2 production from chemical hydride hydrolysis by cryogel-M composites. • Soft, superporous cryogel reactors for energy applications

  4. Electrochemical characterization of aminated acrylic conducting polymer

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Norma Mohammad [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Heng, Lee Yook [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ling, Tan Ling [Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  5. Low temperature gas plasma-induced graft polymerization of acrylic acid onto polypropylene film%低温等离子体引发聚丙烯薄膜气相接枝丙烯酸

    Institute of Scientific and Technical Information of China (English)

    王月然; 王振欣; 魏俊富; 程春祖; 任婉婷; 付中玉; 李健; 聂锦梅

    2011-01-01

    利用等离子体处理聚丙烯(PP)薄膜后在气相环境中引发丙烯酸在其表面接枝聚合.实验结果表明,接枝处理15 min即可使PP薄膜的接触角从97°降至32°,说明亲水性大幅提高.红外光谱和扫描电镜分析表明,丙烯酸已接枝在PP薄膜表面,生成了众多l~2 μm的凸起物.经l0 min沸水处理后,接枝PP薄膜的水接触角无明显增加,揭示出气相接枝可有效克服单纯等离子体处理存在的时效性问题.在55℃下接枝丙烯酸15 min,PP薄膜的接枝率和接触角可分别达到0.45%和32°,是较优的接枝反应条件.%Low temperature gas plasma-induced graft polymerization of acrylic acid (AAc) onto polypropylene (PP) film was performed. The experimental results showed that 15 minutes' grafting was sufficient enough to decrease the water contact angle ( WCA ) of PP film from 97° to 32°, which indicated a great improvement in its hydrophilicity. FTIR-ATR and SEM studies confirmed the grafting of AAc onto PP film, which resulted in the formation of many bump-like substances in a size of 1 -2 μm. The WCA did not increase significanfiy even after being treated in the boiling water for 10 min, which indicated that the ageing effect of merely plasma-treated PP film was effectively overcome. After grafting for 15 rain at 55 C, the degree of grafting and WCA of the grafted sample reached 0. 45% and 32°, respectively.These parameters were regarded as optimum grafting conditions.

  6. Nanocellulose whiskers’dual grafting with acrylic acid and acrylamide for Cu2+ adsorption%纳米纤维素晶须双重接枝共聚物对Cu2+的吸附

    Institute of Scientific and Technical Information of China (English)

    叶代勇; 杨洁

    2014-01-01

    Acrylic acid (AA)and acrylamide (AM)were simultaneously grafted onto the surface of nanocellu-lose whiskers (NCW).The AA,AM-g-NCW was analyzed by infrared spectroscopy (FT-IR)and polarizing op-tical microscopy (POM).The effects of the adsorption time,adsorption temperature,pH values and initial concentration on its Cu2+ adsorption properties were studied.The results showed that AA and AM were suc-cessfully grafted onto the NCW.The added Cu2+ ions influenced the liquid crystalline texture of AA,AM-g-NCW.AA,AM-g-NCW had best adsorption effect for Cu2+ when the adsorption time was 8 h,the adsorption temperature was 35 ℃ and the pH value was 6-8.The maximum adsorption capacity was 38.96 mmol/g for the Cu2+ ions.The adsorption isotherm could be well fitted in with Langmuir equation.%将丙烯酸和丙烯酰胺接枝到纳米纤维素晶须表面,制备出双重接枝共聚物。通过红外光谱和偏光显微镜分析表征双重接枝共聚物的官能团和液晶性能,研究了其对Cu2+的吸附性能,考察了吸附时间、吸附温度、pH 值和初始浓度对吸附性能的影响。实验结果表明,丙烯酸和丙烯酰胺成功接枝到纳米纤维素晶须的表面;Cu2+的加入影响了双重接枝共聚物的液晶织构;在吸附时间为8 h,吸附温度为35℃,pH 值为6~8时,双重接枝共聚物对 Cu2+具有最佳的吸附效果,最大的吸附容量为38.96 mmol/g,吸附过程符合Langmuir方程。

  7. Vinyl Acetate/butyl acrylate/acrylate Research of Ternary Soap-free Emulsion Polymerization

    Directory of Open Access Journals (Sweden)

    Xiao Li-guang

    2016-01-01

    Full Text Available Through the vinyl acetate/butyl acrylate/acrylic acrylic emulsion preparation without soap vinegar, with solid content, gel, emulsion stability and film forming properties and tensile strength as the main index to study the effect of raw materials on the properties of emulsion. Through the infrared spectrometer soap-free emulsion for microscopic analysis research. Study of the ternary soap-free vinegar acrylic emulsion with good performance.

  8. Radiation curing applications of palm oil acrylates

    International Nuclear Information System (INIS)

    Various palm oil based urethan acrylate prepolymers (UP) were prepared from palm oil based polyols, diisocyanate compounds and hydroxyl terminated acrylate monomers by following procedure derived from established methods. The products were compared with each other in term of their molecular weights (MW), viscosities, curing speed by UV irradiation, gel contents and film hardness. The molecular structure of diisocyanate compounds and hydroxyl acrylate monomers were tend to determine the molecular weights and hence viscosities of the final products of urethan acrylate prepolymers (UP), whereas, the MW of the UP has no direct effects on the UV curing properties of the prepolymers. (author)

  9. 两性聚羧酸类高聚物阳离子丙烯酸酯单体 DAC 的制备及其性能%Preparation and performance of cationic acrylate monomer (DAC) for amphoteric carboxylic acid polymer

    Institute of Scientific and Technical Information of China (English)

    陈宝璠

    2015-01-01

    以丙烯酸甲酯(MA)与2氯乙醇(CE)为反应原料,通过酯交换反应制备了丙烯酸氯乙醇酯(CA)中间体,再将 CA 与三甲胺(TMA)水溶液反应,合成了一种用于制备两性聚羧酸类高聚物的阳离子丙烯酸酯单体(丙烯酰氧乙基三甲基氯化铵,DAC).采用 FTIR 和1 HNMR 对 DAC 结构进行了表征,并考察了 n(TMA)/n (CA)、催化剂用量、阻聚剂用量、反应温度和反应时间对 CA 转化率和 DAC 质量分数的影响.结果显示:最佳制备工艺条件为 n(TMA)/n(CA)=1.2,催化剂用量为 CA 中间体质量的4.5%,阻聚剂用量为 CA 中间体质量的0.6%,反应温度为50℃,反应时间为3 h.以 DAC 为阳离子单体,与丙烯酸(AA)、聚乙二醇单甲醚丙烯酸酯(MPEGAA)通过反相乳液共聚合制得两性聚羧酸类高聚物,该高聚物具有优异的保坍性和较高的早期抗压强度.%A cationic acrylate monomer,[2-(acryloyloxy)ethyl]trimethyl ammonium chloride,DAC),used for synthetizing amphoteric carboxylic acid polymer was prepared by reaction of 2-chloroethyl acrylate (CA)inter-mediate and trimethylamine (TMA)aqueous solution.The 2-chloroethyl acrylate (CA)intermediate was pre-pared by transesterification of methyl acrylate and 2-chloroethanol.The DAC structure was identified by means of FTIR and 1 HNMR.The influences of n (TMA)/n (CA),dosages of catalyst and polymerization inhibitor,reaction temperature and reaction time were investigated with the conversion rate of CA and mass fraction of DAC.The results show that the optimal technological conditions for the preparation includes:n(TMA)/n(CA)is 1.2,the dosage of catalyst is 4.5% and the dosage of polymerization inhibitor is 0.6%according to the mass of CA,the reaction temperature is 50 ℃ and the reaction time is 3 h.And the amphoter-ic carboxylic acid polymer was prepared by means of inverse emulsion copolymerization of DAC,acrylic

  10. Preparation and Adsorption Properties of Carboxymethylcellulose Graft Acrylic Acid Resin for Cr(Ⅵ)%羧甲基纤维素接枝丙烯酸复合材料的制备及对Cr(Ⅵ)的吸附研究

    Institute of Scientific and Technical Information of China (English)

    徐浩龙

    2012-01-01

    Graft copolymerization of acrylic acid on carboxymethylcellulose, using potassium persulfate as the inliator and N.N-methylenebisacrylamide as the cross-linking agent, was prepared from carboxymethylcellulose and acrylic acid by the method of copolymerization and cross-linking, and applied to Cr( VI) absorbefacienL The results show that the adsorption rate is more than 95% , when pH =4. 5, adsorbent period was 2 hours and concentration of Cr( Ⅳ) is 100 mg/L%以过硫酸钾为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,采用自由基聚合法使羧甲基纤维素与丙烯酸进行接枝共聚,制备了一种羧甲基纤维素接枝聚丙烯酸Cr(Ⅵ)吸附材料,研究了原料配比、pH、溶液浓度、吸附时间和温度对吸附性能的影响.结果表明:羧甲基纤维素与丙烯酸的质量比为3∶17、pH =4.5时复合材料表现出最佳吸附性能;吸附时间为2h时,吸附率大于95%.

  11. Surface modification of nanoparticles for radiation curable acrylate clear coatings

    Science.gov (United States)

    Bauer, F.; Gläsel, H.-J.; Hartmann, E.; Bilz, E.; Mehnert, R.

    2003-08-01

    To obtain transparent, scratch and abrasion resistant coatings a high content of nanosized silica and alumina filler was embedded in radiation-curable acrylate formulations by acid catalyzed silylation using trialkoxysilanes. 29SiMAS NMR and MALDI-TOF mass spectrometry were employed to elucidate the structure of the surface-grafted methacryloxypropyl-, vinyl- and n-propyl-trimethoxysilane. In accordance with NMR findings, MALDI-TOF MS showed highly condensed oligomeric siloxanes of more than 20 monomeric silane units. A ladder-like structure of bound polysiloxanes is proposed rather than a simplified picture of tridentate silane bonding. Hence, silane coupling agents do not only modify the chemical nature of the filler surface but also strongly effect the rheological properties of the acrylate nanodispersions.

  12. 丙烯酸接枝改性聚丙烯非织造布及其对染料过滤吸附与解吸作用的研究%Photo-grafting modification of polypropylene nonwovens with acrylic acid and its filtration adsorption and desorption toward cationic dye

    Institute of Scientific and Technical Information of China (English)

    艾丽; 刘颖; 王宇阳; 石小丽; 朱新生

    2014-01-01

    采用紫外照射方法对聚丙烯( PP)非织造布进行改性。将丙烯酸( AA)接枝聚合到PP非织造布表面,制得PP-g-AA改性非织造布。研究了交联剂浓度对接枝率的影响,并研究了接枝前后非织造布的形态和微观结构的变化,以及接枝非织造布对染液的吸附与解吸行为及其透水性。结果表明:AA可有效接枝到PP非织造布上;接枝非织造布对阳离子红X-GRL的最大吸附量为146.4 mg/g,显示出优异的吸附性能;等温吸附符合Freundlich模型,吸附动力学模型符合Lagegren准二级动力学方程;接枝非织造布的水通量表现出强烈的酸碱性和电解质依赖性;接枝PP非织造布对阳离子染料的吸附能再生循环利用。采用吸附过滤方式使用PP-g-AA非织造布可对印染废水进行深度处理。%Poly( acrylic acid) was grafted onto the polypropylene nonwovens surfaces under ultraviolet irradiation . PP-g-AA nonwovens was made by grafting poly (acrylic acid) (PAA) on the surface of PP.The effect of crosslinking agent on the grafting degree , as well as the microstructure of the grafted nonwovens and ungrafted nonwovens , the adsorption , desorption and water permeability of the grafted nonwovens were carefully investigated .The results indicated that , poly ( acrylic acid ) was enwrapped evenly on the fiber surfaces.The maximum equilibrium adsorption capacity of the cationic dye was up to 146.4 mg/g in this experimental setup , indicating the excellent adsorption performance .The absorption isotherm of the grafted nonwovens follows Freundlich model .The dynamic adsorption process is in accordance with the Lagergren’s pseudo-second order model .The water permeability strongly was depended on acidity and the ionic strength of electrolyte solution .The results of the repeating adsorption and desorption recycles implies reusability , and applicability for deeply treating the dyeing and printing wastewaters .

  13. Radiopurity measurement of acrylic for DEAP-3600

    International Nuclear Information System (INIS)

    The spherical acrylic vessel that contains the liquid argon target is the most critical detector component in the DEAP-3600 dark matter experiment. Alpha decays near the inner surface of the acrylic vessel are one of the main sources of background in the detector. A fraction of the alpha energy, or the recoiling nucleus from the alpha decay, could misreconstruct in the fiducial volume and result in a false candidate dark matter event. Acrylic has low levels of inherent contamination from 238U and 232Th. Another background of particular concern is diffusion of 222Rn during manufacturing, leading to 210Pb contamination. The maximum acceptable concentrations in the DEAP-3600 acrylic vessel are ppt levels of 238U and 232Th equivalent, and 10−8 ppt 210Pb. The impurities in the bulk acrylic will be measured by vaporizing a large quantity of acrylic and counting the concentrated residue with ultra-low background HPGe detectors and a low background alpha spectrometer. An overview of the acrylic assay technique is presented

  14. Radiopurity measurement of acrylic for DEAP-3600

    Energy Technology Data Exchange (ETDEWEB)

    Nantais, C. M.; Boulay, M. G. [Department of Physics, Engineering Physics, and Astronomy, Queen' s University, Kingston, Ontario K7L 3N6 (Canada); Cleveland, B. T. [SNOLAB, Lively, Ontario P3Y 1N2 Canada and Department of Physics, Laurentian University, Sudbury, Ontario P3E 2C6 (Canada)

    2013-08-08

    The spherical acrylic vessel that contains the liquid argon target is the most critical detector component in the DEAP-3600 dark matter experiment. Alpha decays near the inner surface of the acrylic vessel are one of the main sources of background in the detector. A fraction of the alpha energy, or the recoiling nucleus from the alpha decay, could misreconstruct in the fiducial volume and result in a false candidate dark matter event. Acrylic has low levels of inherent contamination from {sup 238}U and {sup 232}Th. Another background of particular concern is diffusion of {sup 222}Rn during manufacturing, leading to {sup 210}Pb contamination. The maximum acceptable concentrations in the DEAP-3600 acrylic vessel are ppt levels of {sup 238}U and {sup 232}Th equivalent, and 10{sup −8} ppt {sup 210}Pb. The impurities in the bulk acrylic will be measured by vaporizing a large quantity of acrylic and counting the concentrated residue with ultra-low background HPGe detectors and a low background alpha spectrometer. An overview of the acrylic assay technique is presented.

  15. Synthesis and Antibacterial Activity of the Carboxymethyl Chitosan Graft Poly(Acrylic Acid)Superabsorbent Resins%羧甲基壳聚糖接枝聚丙烯酸高吸水树脂的制备及抑菌性能

    Institute of Scientific and Technical Information of China (English)

    王开明; 黄惠莉; 王忠敏

    2012-01-01

    以壳聚糖为原料,在碱性条件下与氯乙酸反应,合成了具有良好水溶性的羧甲基壳聚糖.以合成的水溶性羧甲基壳聚糖和丙烯酸为原料,通过接枝共聚反应合成了具有一定抑菌性能的羧甲基壳聚糖接枝聚丙烯酸高吸水树脂.探讨了羧甲基壳聚糖的合成条件,研究了羧甲基壳聚糖用量对树脂吸水性能和抑菌性能的影响.结果表明,当碱与壳聚糖的质量比为6:1,氯乙酸与壳聚糖的质量比为5.5:1时,羧甲基壳聚糖的产率和取代度均较高,在水中的水溶性较好;在相同的合成条件下,当羧甲基壳聚糖用量为丙烯酸质量的1.80%时,树脂具有较高的吸水性能及良好的抑菌性能,且均优于壳聚糖接枝聚丙烯酸高吸水树脂,其吸水倍率为980 g/g,对大肠杆菌和金黄色葡萄球菌均有抑制其生长的作用,抑菌率分别为91.7%和70.6%.%The carboxymethyl chitosan which had good water-solubility was synthesized by the reaction between chitosan and chloroacetic acid under alkaline condition. After that, a series of carboxymethyl chitosan graft poly ( acrylic acid ) superabsorbent resins which had antibacterial activity were synthesized by graft polymerization between carboxymethyl chitosan and acrylic acid. The synthesis conditions of carboxymethyl chitosan were investigated, the effects of carboxymethyl chitosan content on the water absorbency and antibacterial activity of the superabsorbent resins were studied. The result showed that when the mass ratio of alkali to carboxymethyl chitosan was 6:1 and the mass ratio of chloroacetic acid to carboxymethyl chitosan was 5.5:1, the carboxymethyl chitosanthe had good yield and degree of substitution. Under the same conditions of synthesis, when the content of carboxymethyl chitosan was 1.8% of acrylic acid mass, the superabsorbent resin had better water absorbency and antibacterial activity, moreover, which were higher than chitosan graft poly ( acrylic acid

  16. Study on the Protein Diffusion Behavior in the Poly(Acrylamide-co-Acrylic Acid) Copolymer by FRAP Technique%应用FRAP技术评价蛋白在聚丙烯酰胺-丙烯酸凝胶中的扩散行为

    Institute of Scientific and Technical Information of China (English)

    崔金磊; 周稳稳; 邱玉琴; 高云华

    2011-01-01

    The drug release behavior from the carrier is bound up with the carrier s structure. In this paper, a series of poly (acrylamide-co-acrylic acid) hydrogels with different acrylamide/ acrylic acid ratios have been successfully synthesized by aqueous polymerization. These co-polymers were characterized with FTIR technique to confirm the co-polymer formation. Fluorescence recovery after photobleaching (FRAP) technique was used to investigate the diffusion behavior of fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) in these co-polymer hydrogels? And a confocal laser scanning microscopy was applied to obtain high resolution images in real time. The results showed that the diffusion coefficient of FITC-BSA was influenced by the ratio between the acrylamide and acrylic acid in co-polymer and the co-polymer hydrogels synthesized may have potential application in controlled protein delivery system.%药物分子从药物载体中的释放行为与载体的结构有密切关系.本实验中采用丙烯酰胺和丙烯酸等材料,运用水相沉淀的方法,制备了4种不同单体配比的聚丙烯酰胺-丙烯酸(P(Am-co-Ac)共聚物水凝胶.运用红外分析方法对P (Am-co-Ac)组成进行表征.使用荧光漂白恢复法(FRAP,fluorescence recovery after photobleaching)观察荧光素FITC标记的牛血清白蛋白(BSA)在聚丙烯酰胺-丙烯酸中的扩散行为,并以激光共聚焦显微镜进行实时成像.实验表明,FITC-BSA在不同单体配比的共聚物中的扩散系数是不同的.通过调节聚合物中单体的配比能够达到控制蛋白释放速率的作用,从而为调控蛋白和多肽类药物的缓控释放提供了可能性.

  17. Occupational respiratory disease caused by acrylates.

    Science.gov (United States)

    Savonius, B; Keskinen, H; Tuppurainen, M; Kanerva, L

    1993-05-01

    Acrylates are compounds used in a variety of industrial fields and their use is increasing. They have many features which make them superior to formerly used chemicals, regarding both their industrial use and their possible health effects. Contact sensitization is, however, one of their well known adverse health effects but they may also cause respiratory symptoms. We report on 18 cases of respiratory disease, mainly asthma, caused by different acrylates, 10 cases caused by cyanoacrylates, four by methacrylates and two cases by other acrylates. PMID:8334539

  18. The development of palm oil based acrylated resins and their applications

    International Nuclear Information System (INIS)

    Since Malaysia provides 57 and 75% of the world's production and exports of palm oil respectively, it is natural that we should be in the forefront of the research of widening the use of palm oil in oleochemicals industry, which are currently increase in popularity. The presence of unsaturation in the fatty acids of vegetable oils such as palm oil, technically paves the way for the production of acrylated resins. The more unsaturated the oil, the better it will perform in the radiation curing related applications. The first acrylated palm oil was synthesised in early 1989, through acrylation process, whereby, acrylic acid is introduced into oxirane group of the epoxidised palm oil products, EPOP, at 100-130 deg C in the presence of triethylamine, TEA, as a catalyst and 4-methoxyphenol as an inhibitor. The acrylated products namely epoxidised palm oil (olein) acrylate, EPOLA/EPOPA, was found curable when subjected to UV or EB irradiations. The EPOLA based formulated resins were satisfactorily been used as radiation curable coating materials on various substrates such as woods, bamboos, glass, ceramics and metals without any major defects at reasonably fast cure rate. Preliminary investigations also revealed their potentials as radiation curable pressure sensitive adhesives and printing inks. Isocyanation of EPOLAs at 50 to 90deg C with the presence of 1% inhibitor such as 4-methoxyphenol resulted in resins called Palm oil based urethane acrylates, POBUA. This newly synthesised resins possess certain advantages over EPOLA such as higher molecular weight, better crosslinking density, abrasion resistance, tensile properties and also pendulum hardness. Early results might suggest that POBUA is in a better position to be used as resins for radiation curing of surface coating applications

  19. Crystal structure transformation in potassium acrylate

    Science.gov (United States)

    Pai Verneker, V. R.; Vasanthakumari, R.

    1983-10-01

    Potassium acrylate undergoes a reversible phase transformation around 335°K with an activation energy of 133 kcal/mole. Differential scanning calorimetry and high temperature X-ray powder diffraction techniques have been used to probe this phenomenon.

  20. 海藻酸钠接枝丙烯酸-丙烯酰胺共聚物/凹凸棒石复合材料的制备与表征%Preparation and Characterization of Sodium Alginate with Acrylic Acid-acrylamide Copolymers/Attapulgite Composites

    Institute of Scientific and Technical Information of China (English)

    胡盛; 姚雪; 周红艳; 段雯怡; 田大听; 张升晖

    2012-01-01

    Sodium alginate grafted acrylic acid-acrylamide copolymers/attapulgite composite using sodium alginate( SA), acrylic acid( AA), acrylamide( AM)was synthesized by aqueous solution polymerization with and attapulgite(AT)as raw material, potassium persulfate as initiator, and N, N-methylene-bis-acrylamide as crosslinker. The effects of the synthesis factors on water absorbency were investigated. The composites were characterized by FTIR and SEM. The results showed that when the mass ratio of acrylamide: acrylic acid was 5:1, the content of sodium alginate, attapulgite, crosslinker and initiator was 15% , 25% , 0. 095% , 0. 55%(compare to the mass of monomer), respectively, and the absorbency of the composites was highest and the water absorbent rate of the sample was 1 693.3 g·g-1 at 80℃. The FT-IR spectra showed that sodium alginate and AT participated in graft polymerization reaction with A A and AM. The structure of the sodium alginate with acrylic acid-acrylamide copolymers/attapulgite composites shown by SEM was tight but own porous surface and different sizes of holes which are beneficial to improve the water absorbent rate.%以凹凸棒石(AT)为原料、过硫酸钾为引发剂、N,N-亚甲基双丙烯酰胺为交联剂、丙烯酰胺(AM)、丙烯酸(AA)两种单体同时对海藻酸钠(sA)进行接枝改性,采用水溶液聚合法制备了海藻酸钠接枝丙烯酸-丙烯酰胺共聚物/凹凸棒石复合材料.考察了各合成因素对复合材料吸液倍率的影响,并采用FTIR、SEM对复合材料进行了表征.结果表明,当丙烯酰胺与丙烯酸的质量比为5∶1、海藻酸钠质量分数为15%(占单体丙烯酸质量,下同)、凹凸棒石用量为25%、交联剂用量为0.095%、引发剂用量为0.55%和反应温度为80℃时,制备的复合材料的吸蒸馏水倍率最高,达到l 693.3 g/g.FTIR表明,海藻酸钠、丙烯酸、丙烯酰胺和凹凸棒石共同参与了接枝聚合反应.SEM表明,凹凸棒石的引入,

  1. Resistance of acrylic vessel to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Andre Cavalcanti; Menezes, Maria Angela de B.C.; Pereira, Marcio Tadeu; Rocha, Nirlando Antonio; Vilela, Jefferson Jose, E-mail: andreccarneiro@gmail.com, E-mail: menezes@cdtn.br, E-mail: mtp@cdtn.br, E-mail: nar@cdtn.br, E-mail: jjv@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Braga, Mario Roberto Martins S.S., E-mail: mariomartins@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2013-07-01

    This paper describes the preliminary studies made in acrylic material in order to verify the effects of radiolysis in acrylic recipients in which the uranium ore standards are conditioned and check if the material is able to keep the {sup 222}Rn inside the vessel. The preliminary results after gamma irradiation of two kinds of recipients indicate no differences between the vessels irradiated and the ones no irradiated, related to color changes and tension resistance. (author)

  2. Rapid Output Growth of Special Acrylic Esters

    Institute of Scientific and Technical Information of China (English)

    Wang Lianzhi

    2007-01-01

    @@ Acrylic esters are usually classified into general-purpose varieties and special varieties. The production and application of general-purpose varieties is already quite matured in the world and their output growth tends to be flat. Owing to the development of coatings, electronics, automobiles,textiles, printing and construction sectors, especially the application of radiation curing technology in various sectors, special acrylic esters have developed rapidly.

  3. Gel time of calcium acrylate grouting material.

    Science.gov (United States)

    Han, Tong-Chun

    2004-08-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerization reaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reaction kinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time of calcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and an example is provided to verify the proposed formula. PMID:15236477

  4. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerization reaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reaction kinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time of calcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and an example is provided to verify the proposed formula.

  5. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerizationreaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reactionkinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time ofcalcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and anexample is provided to verify the proposed formula.

  6. Property Research of Instant Polymerization Acrylate Size Mixture%瞬时聚合丙烯酸酯浆料的性能研究

    Institute of Scientific and Technical Information of China (English)

    吴长春; 武海良; 沈艳琴; 杨微

    2011-01-01

    探讨在采用瞬时聚合法直接合成固体丙烯酸酯浆料的过程中,疏水性单体丙烯酸丁酯用量对所生成丙烯酸酯浆料性能的影响.测试了不同丙烯酸丁酯用量下反应生成物的水溶性、水溶液黏度及对涤棉粗纱黏附性,并对合成的固体丙烯酸浆料进行红外表征.结果表明:在丙烯酸的中和度为50%、氧化还原引发体系中引发剂为单体量的6%时,丙烯酸丁酯为单体量的25%时合成的浆料性能最好,所生产的浆料为丙烯酸-丙烯酸钠盐-丙烯酸丁酯共聚物.%Effect of hydrophobic monomer butyl acrylate amount on acrylate size mixture property in the process of compounding solid acrylate size mixture directly by instant polymerization was discussed. Water-soluble, solution viscosity and adhesion to polyester cotton roving of polymer were tested in condition of different butyl acrylate amount. Infrared spectroscopy was done on solid acrylate size mixture. The result shows that property of the acrylate size mixture is the best,the size mixture is acrylate,acrylic acid,butyl acrylate copolymer when acrylic acid neutralization degree is 50% ,initiator content in redox initiation system is 6% ,butyl acrylate is 25%.

  7. [MORPHOLOGICAL FEATURES OF RAT MUCOUS MEMBRANE OF THE TONGUE EARLY AFFECTED BY ACRYLIC RESIN MONOMER].

    Science.gov (United States)

    Davydenko, V; Nidzelskiy, M; Starchenko, I; Davydenko, A; Kuznetsov, V

    2016-03-01

    Base materials, made on the basis of various derivatives of acrylic and methacrylic acids, have been widely used in prosthetic dentistry. Free monomer, affecting the tissues of prosthetic bed and the whole body, is always found in dentures. Therefore, study of the effect of acrylic resins' monomer on mucous membrane of the tongue is crucial. Rat tongue is very similar to human tongue, and this fact has become the basis for selecting these animals to be involved into the experiment. The paper presents the findings related to the effect of "Ftoraks" base acrylic resin monomer on the state of rat mucous membrane of the tongue and its regeneration. The microscopy has found that the greatest changes in the mucous membrane of the tongue occur on day 3 and 7 day after applying the monomer and are of erosive and inflammatory nature. Regeneration of tongue epithelium slows down. PMID:27119844

  8. New blends of ethylene-butyl acrylate copolymers with thermoplastic starch. Characterization and bacterial biodegradation.

    Science.gov (United States)

    Morro, A; Catalina, F; Corrales, T; Pablos, J L; Marin, I; Abrusci, C

    2016-09-20

    Ethylene-butyl acrylate copolymer (EBA) with 13% of butyl acrylate content was used to produce blends with 10, 30 and 60% of thermoplastic starch (TPS) plasticized with glycerol. Ethylene-acrylic acid copolymer (EAA) was used as compatibilizer at 20% content with respect to EBA. The blends were characterized by X-ray diffraction, ATR-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), water-Contact Angle measurements (CA), Differential Scanning Calorimetry (DSC) and Stress-strain mechanical tests. Initiated autoxidation of the polymer blends was studied by chemiluminescence (CL) confirming that the presence of the polyolefin-TPS interphase did not substantially affect the oxidative thermostability of the materials. Three bacterial species have been isolated from the blend films buried in soil and identified as Bacillus subtilis, Bacillus borstelensis and Bacillus licheniformis. Biodegradation of the blends (28days at 45°C) was evaluated by carbon dioxide measurement using the indirect impedance technique. PMID:27261731

  9. Occupational fingertip eczema from acrylates in a manicurist

    OpenAIRE

    Denitza Zheleva; Razvigor Darlenski

    2015-01-01

    Occupational hand eczema due to acrylates present in the workplace is a disease frequently reported among dentists, printers, and fiberglass workers. Acrylate monomers are used in the production of a great variety of polymers, including nail cosmetics. Our case report demonstrates a rare clinical presentations of allergic contact dermatitis from acrylic nails. Our patient was working as a manicurist and the diagnostic analyses revealed sensitation to some of the (meth) acrylate compounds of h...

  10. Concepts for stereoselective acrylate insertion

    KAUST Repository

    Neuwald, Boris

    2013-01-23

    Various phosphinesulfonato ligands and the corresponding palladium complexes [{((PaO)PdMeCl)-μ-M}n] ([{( X1-Cl)-μ-M}n], (PaO) = κ2- P,O-Ar2PC6H4SO2O) with symmetric (Ar = 2-MeOC6H4, 2-CF3C6H4, 2,6-(MeO)2C6H3, 2,6-(iPrO)2C 6H3, 2-(2′,6′-(MeO)2C 6H3)C6H4) and asymmetric substituted phosphorus atoms (Ar1 = 2,6-(MeO)2C6H 3, Ar2 = 2′-(2,6-(MeO)2C 6H3)C6H4; Ar1 = 2,6-(MeO)2C6H3, Ar2 = 2-cHexOC 6H4) were synthesized. Analyses of molecular motions and dynamics by variable temperature NMR studies and line shape analysis were performed for the free ligands and the complexes. The highest barriers of ΔGa = 44-64 kJ/mol were assigned to an aryl rotation process, and the flexibility of the ligand framework was found to be a key obstacle to a more effective stereocontrol. An increase of steric bulk at the aryl substituents raises the motional barriers but diminishes insertion rates and regioselectivity. The stereoselectivity of the first and the second methyl acrylate (MA) insertion into the Pd-Me bond of in situ generated complexes X1 was investigated by NMR and DFT methods. The substitution pattern of the ligand clearly affects the first MA insertion, resulting in a stereoselectivity of up to 6:1 for complexes with an asymmetric substituted phosphorus. In the consecutive insertion, the stereoselectivity is diminished in all cases. DFT analysis of the corresponding insertion transition states revealed that a selectivity for the first insertion with asymmetric (P aO) complexes is diminished in the consecutive insertions due to uncooperatively working enantiomorphic and chain end stereocontrol. From these observations, further concepts are developed. © 2012 American Chemical Society.

  11. SYNTHESIS OF BIOCOMPATIBLE ACRYLIC POLYMERS HAVING ASPIRIN-MOIETIES

    Institute of Scientific and Technical Information of China (English)

    LI Fumian; GU Zhongwei; FENG Xinde(S. T. Voong)

    1983-01-01

    Several new monomers, β-(acetylsalicylyloxy)ethyl methacrylate, β-(acetylsalicylyloxy)propyl methacrylate, β-(acetylsalicylyloxy)ethyl acrylate, β-hydroxy-γ-(acetylsalicylyloxy)propyl methacrylate, β-hydroxy-γ-(acetylsalicylyloxy)propyl acrylate have been synthesized from aspirin with corresponding hydroxyalkyl or glycidyl acrylates, and then polymerized by free radical initiator.

  12. 40 CFR 721.5325 - Nickel acrylate complex.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Nickel acrylate complex. 721.5325... Substances § 721.5325 Nickel acrylate complex. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance nickel acrylate complex (PMN P-85-1034) is subject to reporting...

  13. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylate ester copolymer coating. 175.210 Section... COATINGS Substances for Use as Components of Coatings § 175.210 Acrylate ester copolymer coating. Acrylate ester copolymer coating may safely be used as a food-contact surface of articles intended for...

  14. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate...

  15. Amylase catalyzed synthesis of glycosyl acrylates and their polymerization

    NARCIS (Netherlands)

    Kloosterman, Wouter M.J.; Jovanovic, Danijela; Brouwer, Sander; Loos, Katja

    2014-01-01

    The enzymatic synthesis of novel (di)saccharide acrylates from starch and 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and 4-hydroxybutyl acrylate (2-HEA, 2-HEMA and 4-HBA) catalyzed by various commercially available amylase preparations is demonstrated. Both liquefaction and saccharificatio

  16. Measurement of Liquid-Liquid Equilibrium Data for Water-Acrylic Acid-Methyl Isobutyl Ketone%水-丙烯酸-甲基异丁基甲酮三元体系液液平衡数据的测定

    Institute of Scientific and Technical Information of China (English)

    张雷; 张宏勋; 李晨

    2011-01-01

    To assess the capability of methyl isobutyl ketone( MIBK) to separate acetic acid from water, the liquid-liquid equilibrium(LLE) data of the ternary system of water-acrylic acid-MIBK at 20,30,40X1 have been measured. The LLE phase diagram of the investigated system at different temperatures were given. The LLE data were correlated by using Othmer-Tobias and Bachman equations, respectively. The results show that correlation coefficients are more than 0.99, and standard deviations are less than 0. 12. The distribution coefficients and the separation factors at investigated temperatures were calculated.%为了解甲基异丁基甲酮(MIBK)对丙烯酸和水的萃取分离能力,采用液液平衡装置测定了20,30,40℃下的水-丙烯酸-MIBK的液液平衡数据,绘制了相应的液液平衡相图,分别采用Othmer-Tobi-as和Bachman方程对液液平衡数据进行了关联,相关性系数均大于0.99,标准偏差小于0.12,并计算了不同温度下体系的分配系数和分离因子.

  17. Thermodynamic Interactions between Polystyrene and Long-Chain Poly(n-Alkyl Acrylates) Derived from Plant Oils.

    Science.gov (United States)

    Wang, Shu; Robertson, Megan L

    2015-06-10

    Vegetable oils and their fatty acids are promising sources for the derivation of polymers. Long-chain poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) are readily derived from fatty acids through conversion of the carboxylic acid end-group to an acrylate or methacrylate group. The resulting polymers contain long alkyl side-chains with around 10-22 carbon atoms. Regardless of the monomer source, the presence of alkyl side-chains in poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) provides a convenient mechanism for tuning their physical properties. The development of structured multicomponent materials, including block copolymers and blends, containing poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) requires knowledge of the thermodynamic interactions governing their self-assembly, typically described by the Flory-Huggins interaction parameter χ. We have investigated the χ parameter between polystyrene and long-chain poly(n-alkyl acrylate) homopolymers and copolymers: specifically we have included poly(stearyl acrylate), poly(lauryl acrylate), and their random copolymers. Lauryl and stearyl acrylate were chosen as model alkyl acrylates derived from vegetable oils and have alkyl side-chain lengths of 12 and 18 carbon atoms, respectively. Polystyrene is included in this study as a model petroleum-sourced polymer, which has wide applicability in commercially relevant multicomponent polymeric materials. Two independent methods were employed to measure the χ parameter: cloud point measurements on binary blends and characterization of the order-disorder transition of triblock copolymers, which were in relatively good agreement with one another. The χ parameter was found to be independent of the alkyl side-chain length (n) for large values of n (i.e., n > 10). This behavior is in stark contrast to the n-dependence of the χ parameter predicted from solubility parameter theory. Our study complements prior work investigating the interactions between

  18. Thermodynamic Interactions between Polystyrene and Long-Chain Poly(n-Alkyl Acrylates) Derived from Plant Oils.

    Science.gov (United States)

    Wang, Shu; Robertson, Megan L

    2015-06-10

    Vegetable oils and their fatty acids are promising sources for the derivation of polymers. Long-chain poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) are readily derived from fatty acids through conversion of the carboxylic acid end-group to an acrylate or methacrylate group. The resulting polymers contain long alkyl side-chains with around 10-22 carbon atoms. Regardless of the monomer source, the presence of alkyl side-chains in poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) provides a convenient mechanism for tuning their physical properties. The development of structured multicomponent materials, including block copolymers and blends, containing poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) requires knowledge of the thermodynamic interactions governing their self-assembly, typically described by the Flory-Huggins interaction parameter χ. We have investigated the χ parameter between polystyrene and long-chain poly(n-alkyl acrylate) homopolymers and copolymers: specifically we have included poly(stearyl acrylate), poly(lauryl acrylate), and their random copolymers. Lauryl and stearyl acrylate were chosen as model alkyl acrylates derived from vegetable oils and have alkyl side-chain lengths of 12 and 18 carbon atoms, respectively. Polystyrene is included in this study as a model petroleum-sourced polymer, which has wide applicability in commercially relevant multicomponent polymeric materials. Two independent methods were employed to measure the χ parameter: cloud point measurements on binary blends and characterization of the order-disorder transition of triblock copolymers, which were in relatively good agreement with one another. The χ parameter was found to be independent of the alkyl side-chain length (n) for large values of n (i.e., n > 10). This behavior is in stark contrast to the n-dependence of the χ parameter predicted from solubility parameter theory. Our study complements prior work investigating the interactions between

  19. Poly(lauryl acrylate) and poly(stearyl acrylate) grafted multiwalled carbon nanotubes for polypropylene composites

    DEFF Research Database (Denmark)

    Daugaard, Anders Egede; Jankova Atanasova, Katja; Hvilsted, Søren

    2014-01-01

    Two new polymer grafts on an industrial grade multiwalled carbon nanotube (MWCNT) were prepared through a non-oxidative pathway employing controlled free radical polymerization for surface initiated polymer grafting. After photochemical introduction of an ATRP initiator onto the MWCNT......, polymerizations of lauryl or stearyl acrylate were performed, resulting in two novel polymer modifications on the MWCNT (poly(lauryl acrylate) or poly(stearyl acrylate)). The method was found to give time dependent loading of polymers as a function of time (up to 38 wt% for both acrylates), and showed a plateau...... in loading after 12 h of polymerization. The modified nanomaterials were melt mixed into polypropylene composites with very low filler loading (0.3 wt%), whereafter both the thermal and electrical properties were investigated by DSC and dielectric resonance spectroscopy. The electrical properties were found...

  20. Characteristics and mechanisms of acrylate polymer damage to maize seedlings.

    Science.gov (United States)

    Chen, Xian; Mao, Xiaoyun; Lu, Qin; Liao, Zongwen; He, Zhenli

    2016-07-01

    Superabsorbent acrylate polymers (SAPs) have been widely used to maintain soil moisture in agricultural management, but they may cause damage to plants, and the mechanisms are not well understood. In this study, seed germination, soil pot culture, hydroponic experiments, and SAPs degradation were conducted to investigate damage characteristics and mechanisms associated with SAPs application. The Results showed that SAPs inhibited maize growth and altered root morphology (irregular and loose arrangement of cells and breakage of cortex parenchyma), and the inhibitory effects were enhanced at higher SAPs rates. After 1h SAP hydrogels treatment, root malondialdehyde (MDA) content was significantly increased, while superoxide dismutase (SOD) and catalase (CAT) content were significantly decreased. Hydroponics experiment indicated that root and shoot growth was inhibited at 2.5mgL(-1) acrylic acid (AA), and the inhibition was enhanced with increasing AA rates. This effect was exacerbated by the presence of Na(+) at a high concentration in the hydrogels. Release and degradation of AA were enhanced at higher soil moisture levels. A complete degradation of AA occurred between 15 and 20 days after incubation (DAI), but it took longer for Na(+) concentration to decrease to a safe level. These results indicate that high concentration of both AA and Na(+) present in the SAPs inhibits plant growth. The finding of this study may provide a guideline for appropriate application of SAPs in agriculture. PMID:27057990

  1. Acrylic Tanks for Stunning Chemical Demonstrations

    Science.gov (United States)

    Mirholm, Alexander; Ellervik, Ulf

    2009-01-01

    We describe the use of acrylic tanks (400 x 450 x 27 mm) for visualization of chemical demonstrations in aqueous solutions. Examples of well-suited demonstrations are oscillating reactions, pH indicators, photochemical reduction of Lauth's violet, and chemoluminiscent reactions. (Contains 1 figure.)

  2. 羧甲基纤维素接枝丙烯酸/丙烯酰胺缓释肥包膜材料的制备、性能及应用%Preparation of Carboxymethyl Cellulose Graft Acrylic Acid/Acrylamide and Its Application to Coated Urea Slow Release Fertilizer

    Institute of Scientific and Technical Information of China (English)

    徐浩龙

    2012-01-01

    以过硫酸钾为引发剂、N,N'-亚甲基双丙烯酰胺为交联剂,采用水溶液聚合法制备了羧甲基纤维素接枝丙烯酸/丙烯酰胺缓释肥包膜材料,对其吸水性及耐盐性进行了检测,并将其应用于包膜尿素缓释肥的制备.结果表明,在羧甲基纤维素与丙烯酸质量比为3:17、丙烯酰胺用量为12%时,所制备包膜材料在去离子水、自来水和0.4%盐水中的吸水率分别达到743 g.g-1、497 g·g-1和329 g·g-1;包膜尿素缓释肥的氮素释放率满足GB/T 23348- 2009要求,缓释周期达63 d.%Carboxymethyl cellulose graft acrylic acid/acrylamide was prepared by the method of graft copolymerization using potassium persulfate as initiator and N,N'-methylenebisacrylamide as crosslinking agent. The water absorption and salt tolerance of the coating material were determined,and it was applied to preparation of coated urea slow release fertilizer. When the mass ratio of carboxymethyl cellulose to acrylic acid was 3 : 17 and the amount of acrylamide was 12%,the water absorption rate of the coating material was 743 g · g-1,497 g · g-l ,329 g · g-1 in deionized water,tap water,and 0. 4% brine,respectively. The slow-release period of coated urea was 63 d with the nitrogen release rate meeting the standard GB/T-23348-2009.

  3. Avaliação da interação macromolécula/íon Zn+2 em meio aquoso: poli(acrilamida-co-ácido acrílico e taninos Estimation of the macromolecules/zinc ion interaction in the aqueous solution: poly(acrylamide-co-acrylic acid and tannins

    Directory of Open Access Journals (Sweden)

    Márcia D. Clarisse

    2000-09-01

    Full Text Available Este trabalho visa o estudo da interação entre polímeros sintéticos e produtos naturais à base de taninos com o íon zinco (Zn+2 em meio aquoso para sua utilização na remoção de metais em efluentes. Uma série de copolímeros poli(acrilamida-co-ácido acrílico de diferentes composições e homopolímeros de acrilamida e de ácido acrílico foram preparados, assim como, taninos comerciais foram utilizados como recebidos e purificados por extração. Uma metodologia de avaliação da eficiência de interação da macromolécula com o íon Zn+2 foi desenvolvida baseada em curva padrão de intensidade de absorção na região do ultravioleta-visível (UV-VIS em função da concentração do complexo formado, utilizando colorimetria. A capacidade de interação com o íon zinco foi ligeiramente maior para os polímeros sintéticos porém o produto natural tem a vantagem de apresentar um custo mais baixo.The aim of this work was to evaluate the interaction between natural and synthetic macromolecules with the zinc ion (Zn+2 in aqueous solution. Polyacrylamide, poly(acrylic acid and poly(acrylamide-co-acrylic acid were prepared and natural products (tannins were extracted and purified from commercial products. The methodology to evaluate the macromolecule/zinc ion interaction was based on colorimetry by using a standard curve. The interaction efficiency was slightly larger for the synthetic macromolecules when compared to the natural one. Nevertheless, the tanning has lower cost and its use could be recommended.

  4. Role of leucine in isoprenoid metabolism. Incorporation of (3-/sup 13/C)leucine and of (2-/sup 3/H,4-/sup 14/C)-. beta. ,. beta. -dimethyl-acrylic acid into phytosterols by tissue cultures of Andrographis paniculata

    Energy Technology Data Exchange (ETDEWEB)

    Anastasis, P.; Freer, I.; Overton, K.; Rycroft, D.; Singh, S.B. (Glasgow Univ. (UK). Dept. of Chemistry)

    1985-02-01

    (3-/sup 13/C)Leucine is incorporated into phytosterols by tissue cultures of Andrographis paniculata by breakdown to acetyl-CoA and its subsequent incorporation via (3S)-3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) and mevalonic acid; (2-/sup 3/H,4-/sup 14/C)-..beta..,..beta..-dimethylacrylic acid also is not incorporated intact.

  5. Large Acrylic Spherical Windows In Hyperbaric Underwater Photography

    Science.gov (United States)

    Lones, Joe J.; Stachiw, Jerry D.

    1983-10-01

    Both acrylic plastic and glass are common materials for hyperbaric optical windows. Although glass continues to be used occasionally for small windows, virtually all large viewports are made of acrylic. It is easy to uderstand the wide use of acrylic when comparing design properties of this plastic with those of glass, and glass windows are relatively more difficult to fabricate and use. in addition there are published guides for the design and fabrication of acrylic windows to be used in the hyperbaric environment of hydrospace. Although these procedures for fabricating the acrylic windows are somewhat involved, the results are extremely reliable. Acrylic viewports are now fabricated to very large sizes for manned observation or optical quality instrumen tation as illustrated by the numerous acrylic submersible vehicle hulls for hu, an occupancy currently in operation and a 3600 large optical window recently developed for the Walt Disney Circle Vision under-water camera housing.

  6. FT-IR and FT-Raman studies of cross-linking processes with Ca²⁺ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - In moulding sands, Part II.

    Science.gov (United States)

    Grabowska, Beata; Sitarz, Maciej; Olejnik, Ewa; Kaczmarska, Karolina; Tyliszczak, Bozena

    2015-12-01

    The hardening process of moulding sands on quartz matrices bound by polymer binders containing carboxyl and hydroxyl groups can be carried out by using physical (microwave radiation, thermal holding) and chemical (Ca(2+) cations, glutaraldehyde) cross-linking agents. The highest hardening level obtain moulding sand samples containing binders in a form of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) within the microwave radiation field, for which the bending strength is of 1.6 MPa value even after 24h from ending the agent activity. The authors focused, in this study, on finding the reason of this effect. It was shown, by means of the FT-IR and FT-Raman spectroscopic methods, that the chemical adsorption process activated by microwaves plays an essential role. The applied microwaves activate the polar groups present in the polymer composition structure as well as the quartz crystals surfaces (silane groups). Then the chemical adsorption occurs in the binder-matrix system within the microwave radiation field and intermolecular lattices are formed with a participation of hydrogen bridges (SiOH⋯OC, SiOH⋯OH) and COSi type bonds. PMID:26125981

  7. Humidity-constant Packaging Design Based on Spongy Polyurethane-poly(acrylic acid-acrylamide) Intelligent Material%基于多孔聚氨酯-聚丙烯酸/丙烯酰胺智能材料的恒湿包装设计

    Institute of Scientific and Technical Information of China (English)

    万国顺; 赵志江; 武建斌; 黄红军

    2012-01-01

    以自制多孔聚氨酯-聚丙烯酸/丙烯酰胺(PU-PAA/AM)智能恒湿材料为基础,设计了一种具有防震缓冲和恒湿性能的包装材料,根据其吸湿量与吸湿时间、平衡含湿量与相对湿度的关系,提出了通过控制预吸湿时间来实现存储包装内环境湿度恒定的方法和公式。将防震缓冲和恒湿性能有机结合起来,在武器装备贮运包装领域具有很大的应用价值。%A package material integrating humidity constant property and buffer function together was designed based on self-made spongy polyurethane-poly(acrylic acid-acrylamide)(PU-PAA/AM) humidity constant intelligent material.The method and formula to realize constant humidity in packaging internal environment through control of pre-absorption time was put forward according to the relation between moisture content and pre-adsorption time,and equilibrium moisture content and relative humidity.The packaging material integrates buffer function and humidity constant property together,so it is can be widely used in weapons storage packaging and transportation.

  8. METHACRYLATE AND ACRYLATE ALLERGY IN DENTAL STUDENTS.

    Directory of Open Access Journals (Sweden)

    Maya Lyapina

    2013-09-01

    Full Text Available A multitude of acrylic monomers is used in dentistry, and when dental personnel, patients or students of dental medicine become sensitized, it is of great importance to identify the dental ;acrylic preparations to which the sensitized individual can be exposed. Numerous studies confirm high incidence of sensitization to (meth acrylates in dentatal professionals, as well as in patients undergoing dental treatment and exposed to resin-based materials. Quite a few studies are available aiming to evaluate the incidence of sensitization in students of dental medicineThe purpose of the study is to evaluate the incidence of contact sensitization to some (meth acrylates in students of dental medicine at the time of their education, in dental professionals (dentists, nurses and attendants and in patients, the manifestation of co-reactivity.A total of 139 participants were included in the study, divided into four groups: occupationally exposed to (methacrylates and acrylic monomers dental professionals, 3-4 year-of-education students of dental medicine, 6th year–of-education students of dental medicine and patients with suspected or established sensitization to acrylates, without occupational exposure. All of them were patch-tested with methyl methacrylate (MMA, triethyleneglycol dimethacrylate (TREGDMA, ethyleneglycol dimethacrylate (EGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy phenyl]propane (bis-GMA, 2-hydroxyethyl methacrylate (2-HEMA, and tetrahidrofurfuril metacrylate. The overall sensitization rates to methacrylates in the studied population are comparative high – from 25.9% for MMA to 31.7% for TREGDMA. Significantly higher incidence of sensitization in the group of 3-4 course students compared to the one in the group of dental professionals for MMA and TREGDMA was observed. Highest was the incidence of sensitization to ethyleneglycol dimethacrylate, BIS-GMA, 2-HEMA and tetrahydrofurfuryl methacrylate in the group of patients, with

  9. CORROSION INHIBITION OF CASSAVA STARCH GRAFT ACRYL AMIDE COPOLYMER FOR COLD ROLLED STEEL IN HYDROCHLORIC ACID%木薯淀粉接枝共聚物在盐酸介质中对冷轧钢的缓蚀作用

    Institute of Scientific and Technical Information of China (English)

    付惠; 李向红; 李云仙; 刘建祥

    2011-01-01

    采用氧化还原引发体系引发木薯淀粉与丙烯酰胺接枝共聚反应制备的天然木薯淀粉接枝共聚物(SGA),可以作为一种环境友好型“绿色”缓蚀剂。本文用失重法、动电位极化曲线、电化学阻抗(EIS)和扫描电子显微镜(SEM)首次研究了SGA在1.0mol/LHCl溶液中对冷轧钢的缓蚀作用。结果表明,SGA对冷轧钢具有良好的缓蚀作用,在钢表面的吸附符合Langmuir吸附等温式,为混合抑制型缓蚀剂;EIS谱呈半圆容抗弧,电荷转移电阻随缓蚀剂浓度的增加而增大。SEM表明SGA在钢表面吸附形成了致密的缓蚀剂膜层。%Cassava starch graft acryl amide copolymer (SGA) was prepared by grafting acryl amide onto starch with oxidization reduction reaction, which can be used as a good environmentally-friendly "green" inhibitor. The inhibition effect of SGA on the corrosion of cold rolled steel (CRS) in 1.0 mol/L HCl has been studied by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) methods. The results show that SGA is a good inhibitor in 1.0 mol/L HC1 for CRS, and the adsorption of SGA on the CRS surface obeys Langmuir adsorption isotherm. Polarization curves show that SGA is a mixed-type inhibitor in hydrochloric acid. All EIS spectra exhibit one capacitive loop, and the charge transfer resistance increases with the inhibitor concentration. SEM results show that the introduction of SGA into HCl solution results in the formation of a compact and dense inhibitive film on the CRS surface.

  10. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    Science.gov (United States)

    Suwanmala, Phiriyatorn; Hemvichian, Kasinee; Hoshina, Hiroyuki; Srinuttrakul, Wannee; Seko, Noriaki

    2012-08-01

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption.

  11. Acrylic Bone Cements Modified with Starch

    OpenAIRE

    Krilova, V; Vītiņš, V

    2010-01-01

    The successful result of restorative and replacement surgical operation depends significantly on properties of used bone cement. Acrylic bone cements are usually based on methylmethacrylate polymer, while monomer polymerization begins after mixing of components in mixing device and terminates in living tissue. Polymerization of methylmethacrylate is exothermic process, and temperature increase might cause tissue necrosis with concomitant implant aseptic loosening. Developed non-ionogenic and ...

  12. Preparation and Properties of Triethoxyvinylsilane-Modified Styrene - Butyl Acrylate Emulsion Copolymers

    OpenAIRE

    NAGHASH, Hamid Javaherian; KARIMZADEH, Akram; MOMENI, Ahmad Reza

    2007-01-01

    The copolymers of triethoxyvinylsilane (TEVS) with styrene (St), butyl acrylate (BA), and methacrylic acid (MAA) were prepared by emulsion polymerization. The copolymerization was carried out by using auxiliary agents at 90 °C in the presence of potassium peroxodisulfate (KPS) as the initiator. Nonylphenol ethylene oxide -- 40 units (NP-40) and sodium lauryl sulfoacetate (SLSA) were used as nonionic and anionic emulsifiers, respectively. The resulting copolymers were characterized b...

  13. The Effect of Reactives Diluents to the Physical Properties of Acrylated Palm Oil Based Polyurethane Coatings

    OpenAIRE

    Onn Munirah; Mohd Ahmad Faiza; Yhaya Mohd Firdaus

    2016-01-01

    The development of polyurethane with hydroxyl access in a molecule leads to a new alternative of low toxicity green product. Palm oil is one of the major commodities in Malaysia. The potential of palm oil to be used as coatings raw material such as alkyd is limited due to low unsaturated side on fatty acid chains. To overcome this limitation, palm oil was modified through transesterification process to produce polyol. Acrylated isocyanate (urethane oligomer) was then grafted onto polyol to pr...

  14. Synthesis and Application of a New Acrylic Ester Resin for Recycling SIPA from its Water Solution

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new acrylic ester polymer YWB-7 resin was prepared and characterized. The properties of YWB-7 resin were compared with those of the commercial Amberlite XAD-7, Diaion HP2MG and hypercrosslinked macroporous polymer NDA-150 resins. Both surface area and micropore area of YWB-7 resin were bigger than those of XAD-7 resin and HP2MG resin. The YWB-7 resin was successfully employed to recycle 5-sodiosulfoisophthalic acids (SIPA) from its solutions with and without methanol.

  15. SYNTHESIS OF ACRYLIC ESTERS IN PHASE TRANSFER CATALYSIS: KINETICS AND ECOLOGICAL ASPECTS

    Directory of Open Access Journals (Sweden)

    GAGIK TOROSYAN

    2012-06-01

    Full Text Available Phase-Transfer Catalysis (PTC technology is used in the commercial manufacture and also in pollution mitigation treatment processes. In the paper is demonstrated the synthesis of esters of acrylic and metacrylic acids, which have wide applications in the industry for the synthesis of unique polymeric materials, by phase transfer catalysis method. It is necessary to notice that the synthesis of acrylic acids in PTC medium is more important because that compounds are more sensitive at acidic and basic conditions. Here is shown that the offered method has more advantages in comparison with the traditional methods. PTC is characterized by a higher degree of conversion of raw materials into useful products, smaller material and power resources consumption. The offered method for acrylic ester synthesis in comparison with the traditional methods has more advantages: higher process rates, mild reaction conditions, allowing lower energy costs, the complete elimination of hazardous and dangerous organic solvents, all leading to a sharp reduction of air pollution, and volume of generated wastewaters.

  16. Performance comparison of acrylic and thiol-acrylic resins in two-photon polymerization.

    Science.gov (United States)

    Jiang, Lijia; Xiong, Wei; Zhou, Yushen; Liu, Ying; Huang, Xi; Li, Dawei; Baldacchini, Tommaso; Jiang, Lan; Lu, Yongfeng

    2016-06-13

    Microfabrication by two-photon polymerization is investigated using resins based on thiol-ene chemistry. In particular, resins containing different amounts of a tetrafunctional acrylic monomer and a tetrafunctional thiol molecule are used to create complex microstructures. We observe the enhancement of several characteristics of two-photon polymerization when using thiol-acrylic resins. Specifically, microfabrication is carried out using higher writing velocities and it produces stronger polymeric microstructures. Furthermore, the amount of shrinkage typically observed in the production of three-dimensional microstructures is reduced also. By means of microspectrometry, we confirm that the thiol-acrylate mixture in TPP resins promote monomer conversion inducing a higher degree of cross-linked network formation. PMID:27410383

  17. Comparison between poly hydroxy acrylic acid and Van-clear replacing the tradi-tional reagents to detect the cervical hTERC genes by adopting FISH technique%聚羟基丙烯酸和Van-clear替代传统试剂在FIS H法检测宫颈h TERC基因中的应用比较

    Institute of Scientific and Technical Information of China (English)

    陈志强; 代新珍; 王莹; 米贤军; 陈昂; 黄华勇; 钟守军; 邓文同; 刘超凡; 徐秀梅

    2016-01-01

    目的:观察环保固定液(聚羟基丙烯酸、环保透明脱蜡液Van-clear单独或联合)替代传统固定液[4%(体积分数)中性缓冲甲醛、传统透明脱蜡液二甲苯]应用于荧光原位杂交(fluorescence in situ hybridization,FISH)法检测宫颈组织中人端粒酶核糖核酸组分(human telomerase RNA component,hTERC)基因扩增的差异。方法:收集2013年3月到2015年4月于中山市博爱医院妇科住院部送检的255例宫颈组织标本,同一病变部位切取4个样本,分为4组,命名为A、B、C、D组:A组采用4%中性缓冲甲醛固定、二甲苯透明脱蜡制作切片;B组采用聚羟基丙烯酸固定、二甲苯透明脱蜡制作切片;C组采用4%中性缓冲甲醛固定、Van-clear透明脱蜡制作切片;D组采用聚羟基丙烯酸固定、Van-clear透明脱蜡制作切片。采用FISH技术检测4组宫颈标本中hTERC基因。结果:在FISH法检测宫颈各级病变组织hTERC基因时,荧光显微镜下,A、B、C、D四组的组织轮廓和背景均清晰,探针定位准确,可见耀眼的红/绿荧光信号。B、C、D组与A组阳性率相比差异均无统计学意义(P>0.05),且FISH结果符合率高。结论:环保试剂聚羟基丙烯酸、Van-clear有潜在的可能单独或联合替代4%中性缓冲甲醛、二甲苯应用于FISH法检测宫颈hTERC基因。%Objective:To observe the difference of the human telomeres RNA component (hTERC) genes’amplification in the cervical tissue by applying the environment-friendly fixative poly hydroxy acrylic acid and the transparent dewaxing solution Van-clear separately or jointly to replace the traditional fixative 4% (volume fraction)neutral buffered formalin and the conventional transparent dewaxing solu-tion xylene in the use of fluorescence in situ hybridization (FISH)for detection.Methods:In the study, 255 cases of cervical tissue specimens submitted by the Department of Gynecology

  18. Palladium (II) catalyized polymerization of norbornene and acrylates

    Science.gov (United States)

    Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.

    2000-08-29

    Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: [(L)Pd(R)(X)].sub.2, where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.

  19. Palladium (Ii) Catalyzed Polymerization Of Norbornene And Acrylates

    Science.gov (United States)

    Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.

    2001-10-09

    Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.

  20. HYDROLYSIS TRANSFORMATION OF A POLYSTYRENE-b-POLY(tert-BUTYL ACRYLATE)COPOLYMER AND MICELLIZATION PROPERTIES OF THE HYDROLYZED COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A very mild and extremely efficient hydrolysis method for transformation of polystyrene-b-poly(tert-butyl acrylate) (PS-b-PtBA) to polystyrene-b-poly(acrylic acid) (PS-b-PAA)was designed and carried out using more convenient and inexpensive chlorotrimethylsilane/sodium iodide as reagents. The hydrolysis product can self-assemble in aqueous media to give regular micelles with PS block forming the core and PAL4 block forming the corona, or in tetrahydrofuran (THF) to give reverse micelles with the hydrophilic block in the core.

  1. Pulse radiolysis of aqueous solutions of ethyl acrylate and hydroxy ethyl acrylate

    Science.gov (United States)

    Safrany, A.; Biro, A.; Wojnarovits, L.

    1993-10-01

    Ethyl- and hydroxy ethyl acrylate show high reactivities with hydrated electron and hydroxyl radical intermediates of water radiolysis. The electron adduct reversibly protonate with pK values of 5.7 and 7.3. The adducts may take part in irreversible protonation at the β carbon atom forming α-carboxyl alkyl radicals. Same type of radical forms in reaction of acrylates with OH: at low concentration the adduct mainly disappear in self termination reactions. Above 5 mmol dm -1 the signals showed the startup of oligomerization.

  2. Severe Onychodystrophy due to Allergic Contact Dermatitis from Acrylic Nails.

    Science.gov (United States)

    Mattos Simoes Mendonca, Marcela; LaSenna, Charlotte; Tosti, Antonella

    2015-09-01

    Acrylic nails, including sculptured nails and the new ultraviolet-curable gel polish lacquers, have been associated with allergic contact dermatitis (ACD). We report 2 cases of ACD to acrylic nails with severe onychodystrophy and psoriasiform changes including onycholysis and subungual hyperkeratosis. In both cases, the patients did not realize the association between the use of acrylate-based manicures and nail changes. One patient had been previously misdiagnosed and treated unsuccessfully for nail psoriasis. The informed clinician should elicit a history of acrylic manicure in patients with these nail changes, especially in cases of suspected nail psoriasis refractory to treatment. Patch testing is a useful tool in confirming diagnosis. PMID:27170940

  3. Synthesis of Hydrophobically Modified Poly(acrylic acid) gels and Interaction of the gels with Cationic/Anionic Surfactants

    Institute of Scientific and Technical Information of China (English)

    田琴; 唐小真; 庄东青; 章云祥

    2002-01-01

    Poly(acrylic acid)(PAA) gel network with only chemical crosslinking and hydorophobically modified PAA(HM-PAA)gels with both chemical and physical crosslinking were synthesized by radical polymerization in tert-butanol,using ethylene glycol dimethacrylate (EGDMA) as crossliker,and 2-(N-ethylperfluorooctanesulfoamido)ethyl methacrylate (FMA),stearyl acrylate (SA) or lauryl acrylate (LA) as Hydrophobic comonomer respectively.The effcet of the fractions and the species of the hydrophobes on swelling properties of HM-PAA gels and the interaction of gels and surfactants were studied.The results showed that the swelling ratio of HM-PAA gels exhibited a sharp decrease with increasing hydrophobic comomomer comcentration,Which Could be sacribed to the formation of strong hydrophobic association among hydrophobic groups.It was proved that two kinds of binding mechanisms of surfactan/gel and different kinds of hydrophobic clusters existed in gels containing both physical and chemical networks.

  4. Radiation-curing of acrylate composites including carbon fibres: A customized surface modification for improving mechanical performances

    Science.gov (United States)

    Martin, Arnaud; Pietras-Ozga, Dorota; Ponsaud, Philippe; Kowandy, Christelle; Barczak, Mariusz; Defoort, Brigitte; Coqueret, Xavier

    2014-12-01

    The lower transverse mechanical properties of radiation-cured acrylate-based composites reinforced with carbon-fibre with respect to the thermosettable analogues was investigated from the viewpoint of chemical interactions at the interface between the matrix and the carbon material. XPS analysis of representative commercial carbon fibres revealed the presence of a significant amount of chemical functions potentially exerting an adverse effect on the initiation and propagation of the free radical polymerization initiated under high energy radiation. The EB-induced polymerization of n-butyl acrylate as a simple model monomer was conducted in the presence of various aromatic additives exhibiting a strong inhibiting effect, whereas thiols efficiently sensitize the initiation mechanism and undergo transfer reactions. A method based on the surface modification of sized fibres by thiomalic acid is proposed for overcoming the localized inhibition phenomenon and for improving the mechanical properties of the resulting acrylate-based composites.

  5. Characterization of acrylic resins used for restoration of artworks by pyrolysis-silylation-gas chromatography/mass spectrometry with hexamethyldisilazane.

    Science.gov (United States)

    Osete-Cortina, Laura; Doménech-Carbó, María Teresa

    2006-09-15

    A procedure based on the technique of the pyrolysis-GC/MS has been applied, in this work, in order to determine the composition of synthetic acrylic resins employed in artworks. The method is based on the on line derivatization of these resins using hexamethyldisilazane (HMDS). Results obtained have been compared with those others from direct pyrolysis and in situ thermally assisted hydrolysis and methylation with tetramethylammonium hydroxide (TMAH). Sensitivity using HMDS as derivatising reagent is found similar to that from direct pyrolysis and methylation with TMAH. Better resolution of the most representative peaks has been also obtained. Additionally, this method reduces the formation of free acrylic acid molecules during the pyrolysis process and, in consequence, more simplified and well-resolved chromatograms are obtained. Finally, the reported procedure has been successfully used for characterizing several acrylic-based varnishes and binding media currently used in Fine Arts and real pictorial samples from graffiti performed on a Middle Ages bridge. PMID:16797558

  6. Synthesis of acrylates and methacrylates from coal-derived syngas

    Energy Technology Data Exchange (ETDEWEB)

    Spivey, J.J.; Gogate, M.R.; Jang, B.W.L. [Bechtel, San Francisco, CA (United States)] [and others

    1995-12-31

    Acrylates and methacrylates are among the most widely used chemical intermediates in the world. One of the key chemicals of this type is methyl methacrylate. Of the 4 billion pounds produced each year, roughly 85% is made using the acetone-cyanohydrin process, which requires handling of large quantities of hydrogen cyanide and produces ammonium sulfate wastes that pose an environmental disposal challenge. The U.S. Department of Energy and Eastman Chemical Company are sharing the cost of research to develop an alternative process for the synthesis of methyl methacrylate from syngas. Research Triangle Institute is focusing on the synthesis and testing of active catalysts for the condensation reactions, and Bechtel is analyzing the costs to determine the competitiveness of several process alternatives. Results thus far show that the catalysts for the condensation of formaldehyde and the propionate are key to selectively producing the desired product, methacrylic acid, with a high yield. These condensation catalysts have both acid and base functions and the strength and distribution of these acid-base sites controls the product selectivity and yield.

  7. Effects of Ethylene Oxide Spacer Length on solution Properties of Water—Soluble Fluorocarbon—Containing Hydrophobically Associating Poly(Acrylic Acid—co—Rf—PEG Macromonomer)

    Institute of Scientific and Technical Information of China (English)

    杜立斌; 庄东青; 刘寿平; 章云祥

    2003-01-01

    Poly(acrylic acid)s (PAAs) modified with a series of fluorocarbon group (Rf) end-capped Poly(ethylene glycol) (PEG) macromonomers(number of ethylene oxide unit:1,9,23,45) and corresponding copolymers without fluorocarbon end groups were synthesized.It was found that the effect of the hydrophobic association of fluorocarbon groups on the solution viscosity prevailed over that of the hydrogen bond between grafted PEG and the backbone.Rheological measurement on the aqueous solutions of these poly(acrylic acid-co-Rf-PEG macromonomer) s demonstrated that the best thickening performance was shown when the number of ethylene oxide unit (EO number) was 23.

  8. Effect of D-sorbitol on Rheology of Aqueous Alumina Suspensions with Poly(Acrylic Acid)%D-山梨醇对聚丙烯酸-水基氧化铝悬浮液流变性能的影响

    Institute of Scientific and Technical Information of China (English)

    于晓琳; 肖春霞; 郭露村

    2011-01-01

    Effect of D-sorbitol addition on rheological properties of aqueous alumina suspensions dispersed with poly (acrylic acid) (PAA) was investigated.The results showed that for the aqueous alumina suspensions with 30vol%-40vol% solids loadings, small amount of D-sorbitol can significantly enhance the stability of alumina suspensions with PAA at pH=9.0.When the total amount of dispersant was 0.5wt% and the concentration of D-sorbitol was 20%, the viscosity of suspensions was the lowest.In addition, the suspensions dispersed with binary dispersant were less sensitive to ionic strength than the suspensions containing just the PAA.The role of PAA and D-sorbitol in the alumina suspensions was characterized by FTIR spectroscope.Based on the rheology and FTIR measurements, a schematic model was established to depict the mechanism for the effect of D-sorbitol in the presence of PAA.D-Sorbitol was absorbed both on alumina surface and the absorbed PAA, leading to an enhanced steric hindrance thus resulting better stability of the suspensions.%研究了D-山梨醇(D-sorbito1)对聚丙烯酸(poly(acrylic acid)(PAA)稳定的水基氧化铝(A12O3)悬浮液流变性能的影响.实验发现:在pH为9.0时,对于固含量为30vo1%~40vo1%的Al2O3悬浮液,少量D-山梨醇的加入皆能明显提高其分散稳定性.当D-山梨醇的添加量占分散剂总量(0.5wt%)的20%时,悬浮液粘度最低.且添加二元分散剂PAA/D-山梨醇的悬浮液具有更好的抗电解质性能.分别对单一PAA分散的Al2O3及二元分散剂分散的Al2O3进行了红外光谱表征.结合流变与红外实验结果,分析了山梨醇的作用机理:部分山梨醇吸附在Al2O3颗粒表面,部分山梨醇与PAA以氢键形式结合,增大了颗粒间的空间位阻,提高了悬浮液的流变性能.

  9. Swelling Behaviour of a Non-ionic Poly(N-vinyl-2-Pyrrolidone) Gel in a Linear Poly(Acrylic Acid) Solution%非离子聚(N-乙烯基-2-吡咯烷酮)凝胶在线型聚(丙烯酸) 溶液中的溶胀特性

    Institute of Scientific and Technical Information of China (English)

    石家华; 周慧珍; 赵纪冬; 高青雨

    2001-01-01

    The swelling behaviour of a non-ionic poly(N-vinyl-2-pyrrolidone) hydrogel in a linear poly(acrylic acid) solution upon the influence of chain lengh,pH,ionic strength,and water/dimethyl sulfoxide composition was studied.The sharp shrinkage of the gel volume within a narrow range of polyacid concetration takes place as a result of the formation of an intermacromolecular gel-polymer complex on the base of hydrogen bonding.The swelling behaviour strongly depends on the chain length of the polyacid rather than on the ionic strengh.With the increase of pH value and changing water/dimethyl sulfoxide composition the gel reswelling is induced.%研究了在线型聚(丙烯酸)(PAA)溶液中链长、pH、离子强度和水/二甲亚砜混合溶剂组成对非离子聚(N-乙烯基-2-吡咯烷酮)(PVP)水凝胶溶胀特性的影响. 发现聚酸浓度的变化引起凝胶显著的体积相变,这是因为凝胶和聚合物通过氢键形成了大分子间凝胶-聚合物复合物. 凝胶的溶胀特性取决于聚酸的链长而不是离子强度. 随着pH值和水/二甲亚砜混合溶剂组成的变化,凝胶的溶胀率(SR)发生变化.

  10. 高吸水性树脂丙烯酰胺-丙烯酸-对苯乙烯磺酸钠三元共聚物的合成%Synthesis of super absorbent resin acrylamide - acrylic acid - sodium p - styrene sulfonate terpolymer

    Institute of Scientific and Technical Information of China (English)

    余巧玲; 杨燕; 张杰

    2012-01-01

    以丙烯酰胺(AM)、丙烯酸(AA)和对苯乙烯磺酸钠(SSS)为单体,过硫酸钾为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,采用溶液聚合法制备出AM - AA - SSS三元共聚物.结果表明,聚合最佳条件为:AA用量10 mL,AM用量3.3g,SSS用量0.5 g,引发剂用量0.040 g,交联剂用量0.010 g,反应温度60℃.在此条件下,试样的吸蒸馏水倍率为259g/g,吸盐水倍率为42 g/g.%Aciylamide (AM) - acrylic acid (AA) - sodium p - styrene sulfonate ( SSS) terpoly-mer was synthesized by solution polymerization with AM,AA and SSS as monomers,potassium persulfate as initiator, N, N' - methylene bisacrylamide as crosslinking agent. The results showed that the optimum synthetic conditions were AA 10 mL, AM 3.3 g, SSS 0.5 g, initiator 0.040 g, crosslinkingagent 0.010 g, reaction temperature 60 °C . Under these conditions, the water absorption rate of the polymer was 259 g/g,the salt water absorption rate of the polymer was 42 g/g.

  11. Research on Synthesis and Performance of Water Preserver Starch-wafted Acrylic Acid/Zeolite/Fly Ash%淀粉接枝丙烯酸/沸石/粉煤灰保水剂的合成及性能研究

    Institute of Scientific and Technical Information of China (English)

    张秀兰; 栗印环; 郝盼盼; 杨树

    2011-01-01

    With N, N-methylene bisacrylamide as crosslinking agent and potassium persulfate as initiator, the high-hydrophilia compound material starch-grafted acrylic acid/zeolite/fly ash was prepared by using aqueous solution polymerization method and the influence of proportion of zeolite to fly ash, addition amount of starch, doses of crosslinkiag agent and initiator, neutralization degree and reaction temperature on the water absorption rate of the compound material was researched. The results indicated that fly ash and zeolite could be dispersed better in the graft polymer and the water absorption multiple of the compound material to tap water was up to 314.4 g/g and that to tested normal saline was up to 55.7 g/g.%以N,N-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用水溶液聚合法制备淀粉接枝丙烯酸/沸石/粉煤灰高吸水性复合材料,研究了沸石与粉煤灰配比、淀粉添加量、交联剂用量、引发剂用量、中和度及反应温度对复合材料吸水率的影响.结果表明,粉煤灰与沸石在接枝聚合物中可较好的分散,复合材料对自来水的吸水倍率达314.4 g/g,对供试生理盐水的吸水倍率达55.7 g/g.

  12. Investigation of ultraviolet curable waterborne polyurethane acrylate dispersion based on hydroxyl-terminated polybutadiene

    Institute of Scientific and Technical Information of China (English)

    NIU Zhenbin; ZHANG Xingyuan; DAI Jiabing; ZHANG Heping

    2007-01-01

    A new kind of ultraviolet (UV) curable waterborne polyurethane acrylate dispersion was synthesized based on hydroxyl-terminated polybutadiene (HTPB),poly(propylene glycol) (PPG),isophorene diisocyanate (IPDI),2-hydroxy ethyl acrylate (HEA) and dimethylol propionic acid (DMPA) after neutralizing by triethylamine (TEA).2-Hydroxy- 1-[4-(2-hydroxyethoxy) phenyl]-2-methyl-1-propanone (Irgacure 2959) was used as a photoinitiator and deionized water as a diluent.Fourier transform infrared (FTIR) analysis was used to identify the chain structure of the UV-curable polyurethane prepolymer based on HTPB and the curing process.Effects of relative content of HTPB and PPG on emulsion stability,resistance to water and ethanol,thermal stability,compatibility of soft and hard segment,as well as the mechanical property of the cured film were investigated.

  13. Preparation of Conductive Coating Solutions by Blending Waterborne Acrylic Polyurethane Dispersion with Carbon Nanotube

    International Nuclear Information System (INIS)

    Waterborne polyurethane dispersion (WPUD) was synthesized from polycarbonate diol (PCD), isophorone diisocyanate (IPDI) and dimethylol propionic acid (DMPA) as starting materials. Then, waterborne acrylic polyurethane dispersion (AUD) was synthesized by reacting the WPUD with an acrylate monomer, methyl methacrylate (MMA). Subsequently, the AUD was mixed with multi-walled carbon nanotube (MWCNT) to yield a conductive coating solution, and the mixture was coated on the polycarbonate substrate. With increasing the amount of MMA in the AUD, the pencil hardness, abrasion resistance and chemical resistance of the coating films were improved, but the electrical conductivity of the coating films was decreased. On the other hand, the pencil hardness, abrasion resistance and chemical resistance of coating films were decreased, but the electrical conductivity was enhanced with increasing the amount of MWCNT in the conductive coating solutions

  14. 四乙基氢氧化铵改性聚偏氟乙烯接枝聚丙烯酸油水分离膜的制备%Synthesis of Oil/Water Separation Membranes via Grafting Acrylic Acid onto Poly(vinylidene fluoride) Modified by Tetraethyl Ammonium Hydroxide†

    Institute of Scientific and Technical Information of China (English)

    闫凯波; 郭贵宝; 刘金彦

    2016-01-01

    使用四乙基氢氧化铵( TEAH)液相本体改性聚偏氟乙烯( PVDF),以过氧化苯甲酰( BPO)为引发剂,将丙烯酸( AA)接枝到改性PVDF骨架上,合成了聚偏氟乙烯接枝聚丙烯酸( PVDF-g-PAA)共聚物,通过浸没沉淀法制备了PVDF-g-PAA亲水性油水分离膜.通过傅里叶变换红外光谱( FTIR)、扫描电子显微镜( SEM)和过滤试验分析了膜的结构和分离性能.研究了不同接枝条件对PVDF-g-PAA膜接枝率的影响.同时,通过膜接枝率与膜表面接触角的关系确定最佳接枝条件.结果表明, TEAH使PVDF脱去HF产生碳碳双键且PAA接枝到改性的PVDF骨架上,膜内外孔隙分布均匀; PVDF-g-PAA膜的接触角随着接枝率的提高而降低.接枝单体AA含量为45%,接枝温度为85℃,接枝4 h制备的PVDF-g-PAA膜的接枝率为20.1%,孔隙度为65.3%,平均孔径为78.0 nm,接触角为57.5°,且在60 s内接触角降至14.3°;纯水通量提高到571.33 L/( m2·h),截留率和水通量恢复率分别达到94.3%和88.7%,且通量衰减率仅为9.8%.与纯PVDF膜相比, PVDF-g-PAA膜的分离性能显著提高.%Poly(vinylidene fluoride)-graft-poly(acrylic acid)(PVDF-g-PAA) membranes were prepared via phase bulk modification in tetraethyl ammonium hydroxide(TEAH) liquid, grafting acrylic acid(AA) onto PVDF by benzoyl peroxide( BPO) as a initiator. After that, the copolymer was casted into a flat membrane via immersion phase inversion. The chemical composition, morphology and the separation performance of the PVDF-g-PAA membrane were charaterized. Moreover, the effect of variable grafting conditions on grafting de-gree was investigated as well as the optimal surface contact angle for the grafting ration was obtained. It was proved that the PVDF was taken off HF to produce carbon double bonds and acrylic acid was grafted onto the modified PVDF backbones, forming a homogeneous pore distribution in interior and exterior of the membrane. The water contact angle of PVDF

  15. Comparison of classical dermatoscopy and acrylic globe magnifier dermatoscopy

    DEFF Research Database (Denmark)

    Lorentzen, Henrik F; Eefsen, Rikke Løvendahl; Weismann, Kaare

    2008-01-01

    to histopathology diagnoses, assessed dermatoscopic and acrylic globe magnifier photo-slides according to the dermoscopic risk stratification. The observed agreement over all categories between acrylic globe magnifier dermatoscopy and classical dermatoscopy was 94% and Cohen's kappa coefficient was 90% (95...

  16. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  17. Artificial saliva effect on toxic substances release from acrylic resins

    Directory of Open Access Journals (Sweden)

    Kostić Milena

    2015-01-01

    Full Text Available Background/Aim. Acrylic-based resins are intensively used in dentistry practice as restorative or denture-base materials. The purpose of this study was to analyze the surface structure of denture base resins and the amount of released potentially toxic substances (PTS immediately upon polymerization and incubation in different types of artificial saliva. Methods. Storage of acrylic samples in two models of artificial saliva were performed in a water bath at the temperature of 37 ± 1°C. Analysis of the surface structure of samples was carried out using scanning electronic microscopy analysis immediately after polymerization and after the 30-day incubation. The amounts of PTS per day, week and month extracts were measured using high-pressure liquid chromatography. Results. Surface design and amount of PTS in acrylic materials were different and depended on the types and duration of polymerization. The surfaces of tested acrylates became flatter after immersing in solutions of artificial saliva. The degree of acrylic materials release was not dependent on the applied model of artificial saliva. Conclusion. In order to improve biological features of acrylic resin materials, it was recommended that dentures lined with soft or hard coldpolymerized acrylates should be kept at least 1 to 7 days in water before being given to a patient. So, as to reach high degree of biocompatibility preparation of prosthetic restorations from heat-polymerized acrylate was unnecessary. [Projekat Ministarstva nauke Republike Srbije, br. 41017

  18. Occupational fingertip eczema from acrylates in a manicurist

    Directory of Open Access Journals (Sweden)

    Denitza Zheleva

    2015-04-01

    Full Text Available Occupational hand eczema due to acrylates present in the workplace is a disease frequently reported among dentists, printers, and fiberglass workers. Acrylate monomers are used in the production of a great variety of polymers, including nail cosmetics. Our case report demonstrates a rare clinical presentations of allergic contact dermatitis from acrylic nails. Our patient was working as a manicurist and the diagnostic analyses revealed sensitation to some of the (meth acrylate compounds of her new nail cosmetics. Sculptured artificial acrylic and UV-hardened nails s are widely used in developed countries and they are gaining more and more popularity. We expect an increase in the number of cases of contact allergic dermatitis among manicurists and customers.

  19. Biocompatibility of acrylic resin after being soaked in sodium hypochlorite

    Directory of Open Access Journals (Sweden)

    Nike Hendrijatini

    2009-06-01

    Full Text Available Background: Acrylic resin as basic material for denture will stay on oral mucosa for a very long time. The polymerization of acrylic resin can be performed by conventional method and microwave, both produce different residual monomer at different toxicity. Acrylic resin can absorb solution, porous and possibly absorb disinfectantt as well, that may have toxic reaction with the tissue. Sodium Hypochlorite as removable denture disinfectant can be expected to be biocompatible to human body. The problem is how biocompatible acrylic resin which has been processed by conventional method and microwave method after being soaked in sodium hypochlorite solution. Purpose: The aim of this study was to understand in vitro biocompatibility of acrylic resin which has polimerated by conventional method and microwave after being soaked in sodium hypochlorite using tissue culture. Methods: Four groups of acrylic resin plate were produced, the first group was acrylic resin plate with microwave polymeration and soaked in sodium hypochlorite, the second group was acrylic resin plate with microwave polymeration but not soaked, the thirdwas one with conventional method and soaked and the last group was one with conventional method but not soaked, and in 1 control group. Each group consists of 7 plates. Biocompatibility test was performed in-vitro on each material using fibroblast tissue culture (BHK-21 cell-line. Result: The percentage between living cells and dead cells from materials which was given acrylic plate was wounted. The data was analyzed statistically with T test. Conclusion: The average value of living cells is higher in acrylic resin poimerization using microwave method compared to conventional method, in both soaked and non soaked (by sodium hypochlorite group. This means that sodium hypochlorite 0.5% was biocompatible to the mouth mucosa as removable denture disinfectant for 10 minutes soaking and washing afterwards.

  20. Comparison of the Retinal Straylight in Pseudophakic Eyes with PMMA, Hydrophobic Acrylic, and Hydrophilic Acrylic Spherical Intraocular Lens

    Directory of Open Access Journals (Sweden)

    Ya-wen Guo

    2014-01-01

    Full Text Available Purpose. To investigate the intraocular straylight value after cataract surgery. Methods. In this study, 76 eyes from 62 patients were subdivided into three groups. A hydrophobic acrylic, a hydrophilic acrylic, and a PMMA IOL were respectively, implanted in 24 eyes, 28 eyes, and 24 eyes. Straylight was measured using C-Quant at 1 week and 1 month postoperatively in natural and dilated pupils. Results. The hydrophilic acrylic IOLs showed significantly lower straylight values than those of the hydrophobic acrylic IOLs in dilated pupils at 1 week and 1 month after surgery (P0.05. Moreover, no significant difference was found in straylight between natural and dilated pupils in each group at 1 week and 1 month postoperatively (P>0.05. Conclusions. Although the hydrophobic acrylic IOL induced more intraocular straylight, straylight differences among the 3 IOLs were minimal. Pupil size showed no effect on intraocular straylight; the intraocular straylight was stable 1 week after surgery.

  1. Hyperbranched Acrylated Aromatic Polyester Used as a Modifier in UV-Curable Epoxy Acrylate Resins

    Institute of Scientific and Technical Information of China (English)

    KOU,Hui-Guang; ASIF,Anila; SHI,Wen-Fang

    2003-01-01

    The viscosity, the shrinkage degree and the photoplymerization rate of the epoxy acrylate (EB600 ) blended with hyperbranched acrylated aromatic polyester ( HAAPE ) were investigated. The addition of HAAPE into EB600 largely reduces the viscosity of the blend formulation and the shrinkage degree. For example, EB600resin with 50% weight fraction of HAAPE has the 1250 cps of the viscosity and 2.0% of shrinkage degree, while the pure EB600 resin has 3000 cps of the viscosity and 10.5% of shrinkage degree. The photopolymerization rate of the rein is also promoted by HAAPE addition. The good miscibility between HAAPE and EB600 was also observed from the dynamic mechanical analysis. The tensile, flexural and compressive strength, and the thermal properties of the UVcured films are greatly improved.

  2. Synthesis, characterization, swelling and dye adsorption properties of starch incorporated acrylic gels.

    Science.gov (United States)

    Mandal, Bidyadhar; Ray, Samit Kumar

    2015-11-01

    Several hydrogels were prepared by a free radical polymerization of acrylic acid (AA), sodium acrylate (SA) and AA/hydroxy ethyl methacrylate (HEMA) in the presence of starch in water. These starch incorporated acrylic gels were prepared by varying the concentration of the initiator, monomer, crosslinker and the starch. The resulting gels were characterized by FTIR, SEM, XRD, DTA-TGA, pH at point zero charge (PZC), swelling and the diffusion in water. The gels showed high adsorption and removal% of Safranine T (ST) and Brilliant Cresyl Blue (BCB) dyes from water. The swelling and the adsorption data were fitted to different kinetic models and isotherms. Amongst the three kinds of gels, the starch incorporated sodium polyacrylate gel showed the highest adsorption of 9.7-85.3mg/L (97-61% removal) of BCB dye and 9.1-83mg/L (91-60% removal) of ST dye for a feed dye concentration of 10-140mg/L.

  3. Synthesis, characterization, swelling and dye adsorption properties of starch incorporated acrylic gels.

    Science.gov (United States)

    Mandal, Bidyadhar; Ray, Samit Kumar

    2015-11-01

    Several hydrogels were prepared by a free radical polymerization of acrylic acid (AA), sodium acrylate (SA) and AA/hydroxy ethyl methacrylate (HEMA) in the presence of starch in water. These starch incorporated acrylic gels were prepared by varying the concentration of the initiator, monomer, crosslinker and the starch. The resulting gels were characterized by FTIR, SEM, XRD, DTA-TGA, pH at point zero charge (PZC), swelling and the diffusion in water. The gels showed high adsorption and removal% of Safranine T (ST) and Brilliant Cresyl Blue (BCB) dyes from water. The swelling and the adsorption data were fitted to different kinetic models and isotherms. Amongst the three kinds of gels, the starch incorporated sodium polyacrylate gel showed the highest adsorption of 9.7-85.3mg/L (97-61% removal) of BCB dye and 9.1-83mg/L (91-60% removal) of ST dye for a feed dye concentration of 10-140mg/L. PMID:26318665

  4. Preparation and characterization of high salts polymer electrolyte based on poly(lithium acrylate)

    Institute of Scientific and Technical Information of China (English)

    TANG Ai-dong; HUANG Ke-long; PAN Chun-yue; LU Cui-hong

    2005-01-01

    Novel polymer electrolytes were prepared by highly mixing poly(lithium acrylate)(PPALi) with eutectic lithium salts of lithium acetate and lithium nitrate.Poly(lithium acrylate) was preparaed by inverse emulsion polymerization from crylic acid and LiOH.Phase transition temperatures were measured for all the eutectic lithium of binary system samples as a function of the concentration of Li(CH3 COO),and the mixtures exhibit the lowest phase transition temperatures of (448±2) K at about 50% (mass fraction) Li(CH3 COO).Thermogravimetry(TG)and X-ray diffraction(XRD) analysis indicate the formation of a novel polymer-salt complex.The highest conductivity(approximately 4.97 ×10-5S·cm-1) is found at room temperature with the electrolyte composition of eutectic mixture of about 80% (mass fraction),poly(lithium acrylate) 20% under quickly cooling condition,which is 150%higher than that under natural cooling condition.

  5. Preparation of self-crosslinked acrylate emulsion with high elasticity and its rheological properties

    Institute of Scientific and Technical Information of China (English)

    CHEN Li-jun; WU Feng-qin; LI Dong-shuang; YANG Jian; LI Rong-xian

    2008-01-01

    Using butyl acrylate (BA), methyl methacrylate (MMA), methacrylic acid (MAA) and mixed emulsifier as raw materials, the self-crosslinked emulsion was prepared via pre-emulsified and semi-continuous seeded emulsion polymerization technology in the presence of N-hydroxymethyl acrylamide and poly solidum maleate. The influence of mass ratio of BA to MMA, amount of N-hydroxymethyl acrylamide and poly solidum maleate on the rheological properties of the self-crosslinked emulsion was studied. Possible cross-linked mechanism of self-crosslinked monomer was investigated. And the relationship between emulsion viscosity and shear rate was investigated. The results show that the self-crosslinked acrylate emulsion with high elasticity can be synthesized when the mass fractions of BA is 60%, MMA is 40%, and added amount of N-hydroxymethyl acrylamide is 2.5%-3.0% and added amount of poly solidum maleate is 0.3%-0.4%. The self-crosslinkage process of N-hydroxymethyl acrylamide involves two steps. One is copolymer zation of N-hydroxymethyl acrylamide and acrylate, the other is cross-linkage among polymer molecules via condensation reaction of methylol. The emulsion is of rheological properties of pseudo-plastic fluid and belongs to non-Newtonian fluid.

  6. Chemo-enzymatic synthesis route to poly(glucosyl-acrylates) using glucosidase from almonds

    NARCIS (Netherlands)

    Kloosterman, Wouter M. J.; Roest, Steven; Priatna, Siti R.; Stavila, Erythrina; Loos, Katja

    2014-01-01

    Novel types of glucosyl-acrylate monomers are obtained by beta-glucosidase from almond catalyzed glycosidation reaction. The saccharide-acrylate monomers were synthesized by reaction of D-glucose with hydroxyl functional acrylates: 2-hydroxyethyl acrylate (2-HEA), 2-hydroxyethyl methacrylate (2-HEMA

  7. PHOTOINITIATED INVERSE EMULSION POLYMERIZATION OF SODIUM ACRYLATE

    Institute of Scientific and Technical Information of China (English)

    Lian-ying Liu; Zhi-xing Zhang; Wan-tai Yang

    2005-01-01

    Photoinitiated inverse emulsion polymerization of sodium acrylate (AANa) in kerosene was carried out at room or lower temperature, using 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the initiator. Kinetic investigations indicated that the polymerization could be completed in about 30 min and produce polymer with high molecular weight (106~107). It was found that monomer droplets are the main sites for the polymerization (nucleation). With the increase of DMPA concentration, polymerization rate (Rp) reaches a maximum value while molecular weight of the produced polymer has an adverse result, but the dependence of Rp on incident light intensity is similar. Influences of other parameters such as monomer concentration, emulsifier content and reaction temperature, etc. were also studied. At lower pH values of water phase, Rp depends strongly on the pH due to the electrostatic interaction between the ionized radicals and the monomer. At higher pH, Rp shows a slight dependence on pH.

  8. 紫外光接枝丙烯酸改性废胶粉工艺优化及其复合材料的力学性能%Process Optimization of UV-induced Photografting Acrylic Acid onto Waste Rubber Powder and Mechanical Property of the Composite

    Institute of Scientific and Technical Information of China (English)

    丁国新; 夏明; 张智敏; 王彬

    2012-01-01

    The surface of waste rubber powder (WRP) grafted with acrylic acid (APt) was performed under the inducing of ultraviolet (UV) using benzophenone (BP) as photosensitizer. The fabrication parameters were optimized via orthogonal method. The modified WRP/natural rubber (NR) composites were fabricated. The surface morphology and structures of WRP before and after modified, and the effects of WRP content on the mechanical properties of WRP/NR composites were studied. Results show that the highest grafting degree of 3. 38% was gained in the optimized condition with 10wt% AA, 9wt % BP, 150μm grain size of WRP and 4 min of illumination time. The rougher surface of modified WRP was observed when compared with the unmodified samples. The tensile strength and Shore A hardness were increased first, and then decreased with the content of modified WRP increased, and the peak values (27. 28 MPa and 69.2 HSA, respectively) were obtained when 10wt% WRP added.%以丙烯酸为接枝单体,二苯甲酮为光敏剂,在紫外光的引发下对废胶粉进行表面接枝,用正交方法对改性工艺进行了优化,制备了改性废胶粉/天然橡胶复合材料,表征了改性前后废胶粉的表面形貌和结构,考察了其加入量对复合材料力学性能的影响。结果表明:当丙烯酸和二苯甲酮与废胶粉的质量比分别为10%和9%,废胶粉粒径为150μm和光照时间为4min时,为最佳工艺条件,此时接枝率最高,达3.38%;接枝改性后的废胶粉表面粗糙度增加;随改性废胶粉含量的增加,复合材料的拉伸强度和邵氏A硬度先增大后降低,并在质量分数10%时达到最大值,分别为27.28MPa和69.2HSA。

  9. 明胶接枝丙烯酸/丙烯酰胺缓释肥新型包膜材料的制备与应用%Preparation of Coated Material for Slow Release Fertilizer by Grafting Gelatin with Acrylic Acid/Acrylamide and Its Application

    Institute of Scientific and Technical Information of China (English)

    徐浩龙

    2012-01-01

    以过硫酸钾为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,采用自由基聚合法使明胶与丙烯酸/丙烯酰胺进行接枝共聚,制备了一种明胶接枝丙烯酸/丙烯酰胺保水性缓释肥新型包膜材料,进行了吸水、保水、耐盐性检验并应用于包衣尿素的制备.结果表明:明胶用量为2.5%时,材料具有最大吸水率,在去离子水中达775g/g,在自来水中为395g/g.包衣尿素的氮素24h和28d释放率分别为12.11%、73.49%,缓释周期长达56d,达到“缓释肥国家标准”.%A water retention coated material for slow release fertilizer were prepared by graft copolymerization of gelatin with acrylic acid/acrylamide, during wliiuh the potassium persulfate was used as the initiator and the N,N' -methylenebisacrylamide was used as the cross-linking agent. Then, the water absorption, the water retention and the salt tolerance of the coated material were verified in order to apply in coated urea. When gelatin amount was 2.5%, the coated material had the best water absorption that was 775 g/g in deionized water and 395 g/g in tap water. The results showed that release rate of nitrogen from coated urea at 24 h and 28 d was 12.11% and 73.49, and the releasing period of coated urea reached 56 d, which meet the requirments of National Standards fur Slow Release Fertilizers.

  10. Preparation and properties of acrylic acid grafted starch based UV-curing degradable superabsorbent polymer%丙烯酸接枝淀粉基可降解紫外光固化高吸水性树脂的制备与性能

    Institute of Scientific and Technical Information of China (English)

    贺倩; 郭文迅

    2011-01-01

    A degradable superabsorbent resin was prepared by acrylic acid grafted starch with unsaturated polyester-urea amide as a cross-linking agent,a membrane was prepared by the resin,in the condition of UV-curing without adding any photo-initiator.The influence of absorbency rate of the resin,the dosage of cross-linking agent and the UV-curing time on the absorbency were discussed.The results showed that the product had good absorbency ability to different solutions,and the absorbency rate was the fast.Water absorbency in distilled water,tap water,0.9% NaCl,0.9% KC1 solution were 905,350,100,120 g/g,respectively.Moreover,water absorbency in distilled water can reach 200 g/g in 10 min.The degradation originate from surface and evolve towards inside gradually.%以丙烯酸接枝淀粉为基体,不饱和聚酯酰胺脲树脂为交联剂制备出一种可降解高吸水性树脂,该树脂小加任何光引发剂即可紫外光固化成膜.研究了树脂的吸水速率及交联剂的加入量、光同化时间对产品吸水率的影响.结果表明,该高吸水性树脂对不同溶液均具有较好的吸收能力,吸水速度较快,在蒸馏水、自来水、0.9%NaCl溶液、0.9%KCl溶液中的吸水率分别为905,350,100,120g/g;10 min内对蒸馏水的吸收倍率达200 g.该高吸水性树脂的降解从表面开始,逐渐向里面降解.

  11. 聚(丙烯酸-co-丙烯酰胺)/凹凸棒复合材料对亚甲蓝的吸附性能%Adsorption Behaviour of Methylene Blue onto Poly (acrylic acid-co-acrylamide)/Attapulgite Composite

    Institute of Scientific and Technical Information of China (English)

    王永生; 孔莲; 牛文花; 宋海; 任雪峰; 王爱勤

    2011-01-01

    Adsorption properties of cationic dye methylene blue (MB) onto poly (acrylic acid-co-acrylamide)/attapulgite composite clay were investigated.The effects of various experimental parameters such as pH, concentration of the dye, temperature, contact time, adsorbent dosage, ionic strength and surfactant on adsorption process have been investigated.The equilibrium isotherms for the adsorption of the dye were measured experimentally.Results were analyzed by the Langmuir and Freundlich equation at different temperatures and the characteristic parameters for the adsorption isotherm were determined.The adsorption process has been found endothermic for MB in nature.The thermodynamic parameters such as the Gibbs free energy, the change in enthalpy and change in entropy have been calculated.The maximum adsorption capacity for MB was obtained as 1 273.3 mg · g-1 at the temperature of 60 ℃.It was observed that the kinetic data fitted well with a pseudo second-order equation.The results showed that the composite attapulgite clay could be employed as the low-cost alternatives to the traditional agent in the wastewater treatment for the removal of color.%将聚(丙烯酸-co-丙烯酰胺)/凹凸棒复合吸附剂用于亚甲蓝的吸附,研究了时间、浓度、酸度、表面活性剂和离子强度等因素对吸附性能的影响.复合吸附剂对亚甲蓝的吸附是吸热过程,60 ℃时吸附量达到1 273.3 mg·g-1,吸附过程符合Langmuir单分子层吸附等温模式,并计算了热力学常数ΔG、ΔH和ΔS.在实验考察范围内吸附过程均符合准二级动力学特征.该复合吸附剂具有高吸附容量和较快的吸附速率,是良好的亚甲蓝吸附剂.

  12. The Effect of Clay Kind on Properties of Corresponding Poly(Acrylic Acid/Acrylamide/Clay) Superabsorbents%粘土种类对聚丙烯酸俩烯酰胺高吸水树脂性能的影响

    Institute of Scientific and Technical Information of China (English)

    吴紫平; 索红莉; 张腾; 袁慧萍; 王毅; 刘敏; 马磷

    2012-01-01

    选用含量相同的六种不同粘土(煅烧高岭土、蒙脱土、凹凸棒土、膨润土、海泡石和硅藻土),采用反相悬浮法制备了一系列聚(丙烯酸/丙烯酰胺/粘土)高吸水树脂,并比较了不同粘土对高吸水树脂结构、吸水倍率、吸盐水倍率以及保水性能、热稳定性的影响。通过比较发现,添加膨润土的高吸水树脂具有最高的吸水倍率(450 g/g)和吸盐水倍率(92 g/g);添加膨润土和煅烧高岭土均可提高高吸水树脂的保水性能。此外,煅烧高岭土可以更为有效地提高高吸水树脂的热稳定性。%A series of poly(acrylic acid/acrylamide/clay) superabsorbents with 10% different kinds clay,which including calcined kaolin,montmorillonite,attapulgite,bentonite,sepiolite and diatomite,were prepared by inverse suspension polymerization method.The effects of clay kinds on structure,equilibrium water absorbency,equilibrium 0.9% NaCl absorbency,the water-retention capability and thermal stability of the superabsorbent composites were also systematically investigated in the same condition.It is found that the superabsorbent incorporated with bentonite has the best equilibrium water absorbency(450 g/g) and equilibrium 0.9% NaCl absorbency(92 g/g).Moreover,bentonite and calcined kaolin ones show the best capability of maintenancewater.Besides,the calcined kaolin can enhance the thermal stability of corresponding superabsorbent to the highest degree.

  13. Synthesis of iso-butyl acrylate under catalysis of sodium bisulfate monohydrate%硫酸氢钠催化合成丙烯酸异丁酯

    Institute of Scientific and Technical Information of China (English)

    张晓辉; 解李红; 李德鹏; 杨光

    2014-01-01

    Iso-butyl acrylate was synthesized in high yield through the esterification of acrylic acid and iso-butanol under the catalysis of sodium bisulfate monohydrate .The effects of sodium bisulfate monohydrate dosage ,iso-butyl alcohol dosage ,reaction time ,temperature and poly-merization inhibitor dosage on the yield of iso-butyl acrylate were investigated .It was found that ,w hen the molar ratio of iso-butyl alcohol to acrylic acid is fixed at 3∶1 ,the molar ratio of sodium bisulfate monohydrate to acrylic acid is fixed at 2% ,the mass ratio of polymerization inhibitor (hydroquinone) to acrylic acid is fixed at 0 .05% ,the yield of the ester could reach 88 5.1% under a reaction temperature of 115 ℃ and a reflux reaction time of 3 h .%利用一水硫酸氢钠为催化剂使丙烯酸和异丁醇酯化合成了丙烯酸异丁酯;研究了一水硫酸氢钠用量、异丁醇用量、反应时间、温度及阻聚剂用量对丙烯酸异丁酯收率的影响.结果表明,当异丁醇与丙烯酸物质的量之比为3∶1,硫酸氢钠催化剂用量为丙烯酸量的2%,阻聚剂(对苯二酚)用量为丙烯酸质量的00.5%,反应时间为3 h ,反应温度为115℃时,酯化产率可达885.1%.

  14. Performance behavior of modified cellulosic fabrics using polyurethane acrylate copolymer.

    Science.gov (United States)

    Zuber, Mohammad; Shah, Sayyed Asim Ali; Jamil, Tahir; Asghar, Muhammad Irfan

    2014-06-01

    The surface of the cellulosic fabrics was modified using self-prepared emulsions of polyurethane acrylate copolymers (PUACs). PUACs were prepared by varying the molecular weight of polycaprolactone diol (PCL). The PCL was reacted with isophorone diisocyanate (IPDI) and chain was extended with 2-hydroxy ethyl acrylate (HEA) to form vinyl terminated polyurethane (VTPU) preploymer. The VTPU was further co-polymerized through free radical polymerization with butyl acrylate in different proportions. The FT-IR spectra of monomers, prepolymers and copolymers assured the formation of proposed PUACs structure. The various concentrations of prepared PUACs were applied onto the different fabric samples using dip-padding techniques. The results revealed that the application of polyurethane butyl acrylate copolymer showed a pronounced effect on the tear strength and pilling resistance of the treated fabrics.

  15. [Reaction of 1,8-naphthyridine azides with ethyl acrylate].

    Science.gov (United States)

    Livi, O; Ferrarini, P L; Bertini, D; Tonetti, I

    1975-12-01

    The reaction of 1,8-naphthyridine azides with ethyl acrylate leads to the formation of 2-pyrazolines instead of 1,2,3-triazolines. Some of the compounds obtained have undergone pharmacological and microbiological (antibacterial) testing. PMID:1204828

  16. Performance behavior of modified cellulosic fabrics using polyurethane acrylate copolymer.

    Science.gov (United States)

    Zuber, Mohammad; Shah, Sayyed Asim Ali; Jamil, Tahir; Asghar, Muhammad Irfan

    2014-06-01

    The surface of the cellulosic fabrics was modified using self-prepared emulsions of polyurethane acrylate copolymers (PUACs). PUACs were prepared by varying the molecular weight of polycaprolactone diol (PCL). The PCL was reacted with isophorone diisocyanate (IPDI) and chain was extended with 2-hydroxy ethyl acrylate (HEA) to form vinyl terminated polyurethane (VTPU) preploymer. The VTPU was further co-polymerized through free radical polymerization with butyl acrylate in different proportions. The FT-IR spectra of monomers, prepolymers and copolymers assured the formation of proposed PUACs structure. The various concentrations of prepared PUACs were applied onto the different fabric samples using dip-padding techniques. The results revealed that the application of polyurethane butyl acrylate copolymer showed a pronounced effect on the tear strength and pilling resistance of the treated fabrics. PMID:24661889

  17. BARRIER PROPERTY AND STRUCTURE OF ACRYLONITRILE/ACRYLIC COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    YANG Zhenghua; LI Yuesheng

    1997-01-01

    A series of acrylonitrile (AN) copolymers with methyl acrylate (MA) or ethyl acrylate (EA) as comonomer (5-23 wt%) was prepared by free-radical copolymerization. The permeability coefficients of the copolymers to oxygen and carbon dioxide were measured at 1.0 MPa and at 30 ℃, and those to water vapor also measured at 100% relative humidity and at 30 ℃. All the AN/acrylic copolymers are semicrystalline. As the acrylate content increase, the permeability coefficients of the copolymers to oxygen and carbon dioxide are increased progressively, but those to water vapor are decreased progressively. The gas permeability coefficients of the polymers were correlated with free-volume fractions or the ratio of free volume to cohesive energy.

  18. Microorganisms for producing organic acids

    Energy Technology Data Exchange (ETDEWEB)

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  19. Application of reactive acrylate microgels in water-base coatings

    Institute of Scientific and Technical Information of China (English)

    SA Sheng-shu; ZHANG Bao-hua; YANG Qing; WANG Xia-qin; MAO Zhi-ping

    2009-01-01

    Reactive acrylate microgels with different reactive groups such as carboxyl, hydroxide groups had excellent prop-erties such as quick-dry, low viscosity, high adhesion and hardness, which made them extensively used in preparing paints or in coating-modification. Reactive acrylate microgels were prepared by emulsion co-polymerization with zwitterions surfactant, anionic surfactant and nonionic surfactant as co-emulsifier. The water-base baking paints made from reactive acrylate micro-gels and melamine-formaldehyde resin had excellent combination properties. The aluminium powder can be well-dispersed in the paints. The influences of monomer components on the properties of the water-base baking paints were discussed in this paper. And the baking paints were also compared with the marketing solvent acrylate baking paints. It was found that the water-base acrylate amino baking paints had better combination properties than the organic solvent acrylate baking paints, which means that the water-base baking paints had a bright marketing future.

  20. Stabilizing effects of estertins mercaptide (methyl acrylate) for PVC degradation

    Science.gov (United States)

    Zhang, S. H.; Liu, T. M.; Li, J. L.; Wang, C. R.; Li, C.; Wang, Z. Q.

    2016-07-01

    The thermal and UV light (ultraviolet light) stability of PVC films with estertins mercaptide (methyl acrylate), methyltins mercaptide and the compound consisted of estertins mercaptide (methyl acrylate) and hydrotalcite (2:2.5) were investigated by ageing in a circulation oven at 190 °C and irradiating with 72W UV light for 96h, respectively, and then the yellowness and transmission rate were tested by Color Quest XE. Hydrotalcite was proved to have good synergies with estertins mercaptide (methyl acrylate) on improving the thermal stability and UV light stability. The retarding effects of the heat stabilizers to PVC degradation were tested by TGA from 50°C to 600°C. The results show that temperature of HCl evolution from PVC film was improved obviously by compounding with estertins mercaptide(methyl acrylate) and hydrotalcite and estertins mercaptide(methyl acrylate) was found to have a better long term stability. Sn4+ consistence of water and seawater in which films before and after UV light irradiation were soaked for 60 days was analyzed by ICP; the results indicate that the Sn4+ consistence from the films with estertins mercaptide(methyl acrylate) as thermal stabilizer was lower than that from the film with methyltins mercaptide. The crosslink moderately by UV irradiation for PVC films can hold back the dissolution of organotin heat stabilizers from PVC products into water and seawater.

  1. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    International Nuclear Information System (INIS)

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption. - Highlights: ► Adsorbent containing hydroxamic acid group was prepared by radiation-induced grafting. ► The adsorbent exhibited a remarkable % adsorption for Cd2+, Al3+, UO22+, V5+ and Pb2+. ► The selectivity of adsorbent towards metal ions used is in this order: Cd2+>Pb2+> Al3+> UO22+ > V5+.

  2. Synthesis of Citric-Acrylate Oligomer and its in-Situ Reaction with Chrome Tanned Collagen (hide powder)

    International Nuclear Information System (INIS)

    The purpose of this study was to formulate the new combined system of acrylic and citric acids, which has been prepared by free radical polymerization and esterification reaction at the same time to form citric acrylate (CAC) oligomer through ester linkage and low molecular weight (Mw 2241), in compared with polyacrylic acid. The chemical structure and the reaction mechanism of this oligomer were confirmed by different spectroscopic tools (1H, 13C-NMR, ATR-IR), gel permeation chromatography and thermogravimetric analysis (TGA/DTA). The problem of the effect of the masking agents in the chrome tanning of the collagen and the pickling of the hide has been approached from the study of the hydrothermal and mechanical properties, using this new eco-friendly oligomer, which was carried out in-situ treated/grafted chrome tanned collagen (hide powder), and pickled hide. The microemulsion grafting copolymerization of (CAC) using 2.2-azo-bis isobutyronitrile (ABIN), via direct coupling reaction, onto the chrome tanned collagen showed that the free amino groups of the collagen were considered to be a potential site for the in-situ reaction with (CAC) oligomer. Also, using of citric-acrylate (CAC) oligomer, during chrome tanning of leather, instead of the traditional strong acids (sulfuric, hydrochloric and formic) resulted in significant improvement in chrome exhaustion and physical properties

  3. 水溶性羟基丙烯酸酯树脂的合成%Synthesis of Water-soluble Acrylate Resin Containing Hydroxyl Group

    Institute of Scientific and Technical Information of China (English)

    王海波; 唐有根; 刘小平; 佘奕奕

    2009-01-01

    以氧化苯甲酰为引发剂,通过溶液聚合合成了水溶性丙烯酸丁酯-甲基丙烯酸甲酯-丙烯酸-甲基丙烯酸羟乙酯四元共聚物,其结构经~1H NMR,~(13)C NMR和IR表征,热分析结果表明其分解温度为360 ℃~440 ℃.%The water-soluble acrylate resin, the quadripolymer of butyl acrylate-methyl methacrylate-acrylic acid-2-hydroxy-ethyl methacrylate, was synthesized by solution polymerization using benzoyl peroxide as an initiator. The structure was characterized by ~1H NMR, ~(13)C NMR and IR. The decomposition temperature of the quadripolymer was 360 ℃~440 ℃ by thermal analysis.

  4. Synthesis and characterization of copolymers 4,5-dihydroisoxazole and (-)-menthyl acrylates; Sintese e caracterizacao de copolimeros de cadeia lateral derivados de acrilatos de 4,5-di-hidroisoxazol e do (-)-mentol

    Energy Technology Data Exchange (ETDEWEB)

    Passo, Joel A.; Merlo, Aloir A. [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Inst. de Quimica; Eccher, Juliana; Bechtold, Ivan H. [Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil). Campus Universitario Trindade. Dept. de Fisica; Kelly, Stephen M., E-mail: aloir@iq.ufrgs.br [University of Hull, Hull (United Kingdom). Dept. of Chemistry

    2012-07-01

    Five monomers 5-[4-(5-cyano-4,5-dihydroisoxazol-3-yl)phenoxy]undecyl acrylate (7a); n-alkyl 3-{l_brace}4-[5-(acryloyloxyundecyl)oxyphenyl]{r_brace}-4,5-dihydroisoxazole-5-carboxylate (7b,c for n-butyl and n-hexyl, respectively); 3-{l_brace}4-[5-(acryloyloxyundecyl) oxyphenyl]{r_brace}-4,5-dihydroisoxazole-5-carboxylic acid (7d) and (1R,2S,5R)-2-isopropyl-5-methylcyclohexyl acrylate (9) and the corresponding copolymers 10a-d,11 and homopolymers 12 from 7a and 13 from 9 were designed and synthesized. Except for acrylate 9 which is derived from (-)-menthol, all of the monomers belong to the series containing the isoxazoline ring linked to the acrylate unit by a flexible spacer chain of eleven methylene units. They presented low glass temperature and despite birefringence behavior, these copolymers showed no mesomorphic properties. (author)

  5. Impact Delamination and Fracture in Aluminum/Acrylic Sandwich Plates

    Science.gov (United States)

    Liaw, Benjamin; Zeichner, Glenn; Liu, Yanxiong; Bowles, Kenneth J. (Technical Monitor)

    2000-01-01

    Impact-induced delamination and fracture in 6061-T6 aluminum/cast acrylic sandwich plates adhered by epoxy were generated in an instrumented drop-weight impact machine. Although only a small dent was produced on the aluminum side when a hemispherical penetrator tup was dropped onto it from a couple of inches, a large ring of delamination at the interface was observed. The delamination damage was often accompanied by severe shattering in the acrylic substratum. Damage patterns in the acrylic layer include radial and ring cracks and, together with delamination at the interface, may cause peeling-off of acrylic material from the sandwich plate. Theory of stress-wave propagation can be used to explain these damage patterns. The impact tests were conducted at various temperatures. The results also show clearly that temperature effect is very important in impact damage. For pure cast acrylic nil-ductile transition (NDT) occurs between 185-195 F. Excessive impact energy was dissipated into fracture energy when tested at temperature below this range or through plastic deformation when tested at temperature above the NDT temperature. Results from this study will be used as baseline data for studying fiber-metal laminates, such as GLARE and ARALL for advanced aeronautical and astronautical applications.

  6. Microbial transformation of 8:2 fluorotelomer acrylate and methacrylate in aerobic soils.

    Science.gov (United States)

    Royer, Laurel A; Lee, Linda S; Russell, Mark H; Nies, Loring F; Turco, Ronald F

    2015-06-01

    Biotransformation of fluorotelomer (FT) compounds, such as 8:2 FT alcohol (FTOH) is now recognized to be a source of perfluorooctanoic acid (PFOA) as well as other perfluoroalkyl acids. In this study, microbially mediated hydrolysis of FT industrial intermediates 8:2 FT acrylate (8:2 FTAC) and 8:2 FT methacrylate (8:2 FTMAC) was evaluated in aerobic soils for up to 105d. At designated times, triplicate microcosms were sacrificed by sampling the headspace for volatile FTOHs followed by sequential extraction of soil for the parent monomers as well as transient and terminal degradation products. Both FTAC and FTMAC were hydrolyzed at the ester linkage as evidenced by 8:2 FTOH production. 8:2 FTAC and FTMAC degraded rapidly with half-lives ⩽5d and 15d, respectively. Maximum 8:2 FTOH levels were 6-13mol% within 3-6d. Consistent with the known biotransformation pathway of 8:2 FTOH, FT carboxylic acids and perfluoroalkyl carboxylic acids were subsequently generated including up to 10.3mol% of PFOA (105d). A total mass balance (parent plus metabolites) of 50-75mol% was observed on the last sampling day. 7:2 sFTOH, a direct precursor to PFOA, unexpectedly increased throughout the incubation period. The likely, but unconfirmed, concomitant production of acrylic acids was proposed as altering expected degradation patterns. Biotransformation of 8:2 FTAC, 8:2 FTMAC, and previously reported 8:2 FT-stearate for the same soils revealed the effect of the non-fluorinated terminus group linked to the FT chain on the electronic differences that affect microbially-mediated ester cleavage rates.

  7. Self-Assembly of Amphiphilic Block Copolymers Containing Poly(n-octadecyl acrylate) Block in Aqueous Solution

    Energy Technology Data Exchange (ETDEWEB)

    Akiba, Isamu; Akino, Yusuke; Masunaga, Hiroyasu; Sakurai, Kazuo, E-mail: akiba@env.kitakyu-u.ac.jp

    2010-11-15

    Synchrotron small-angle X-ray scattering (SAXS) experiments were carried out for poly(acrylic acid)-block-poly(n-octadecyl acrylate) (PAA-b-PODA) and PAA-b-PODA-b-PAA micelles in aqueous solutions. SAXS results indicated that PAA-b-PODA and PAA-b-PODA-b-PAA formed core-shell micelles with disk-like morphology below melting temperature of PODA in aqueous solutions. The thickness of PAA-b-PODA (diblock copolymer) micelle was larger than that of PAA-b-PODA-b-PAA (triblock copolymer) micelle. The difference of sizes between these micelles was related to difference of molecular architectures of PAA-b-PODA and PAA-b-PODA-b-PAA. PAA-b-PODA micelle showed morphological transition from disk to spherical shape with elevating temperature. On the contrary, PAA-b-PODA-b-PAA micelle maintained disk-like shape above melting temperature, although enlargement of micelle thickness is caused.

  8. Self-Assembly of Amphiphilic Block Copolymers Containing Poly(n-octadecyl acrylate) Block in Aqueous Solution

    Science.gov (United States)

    Akiba, Isamu; Akino, Yusuke; Masunaga, Hiroyasu; Sakurai, Kazuo

    2010-11-01

    Synchrotron small-angle X-ray scattering (SAXS) experiments were carried out for poly(acrylic acid)-block-poly(n-octadecyl acrylate) (PAA-b-PODA) and PAA-b-PODA-b-PAA micelles in aqueous solutions. SAXS results indicated that PAA-b-PODA and PAA-b-PODA-b-PAA formed core-shell micelles with disk-like morphology below melting temperature of PODA in aqueous solutions. The thickness of PAA-b-PODA (diblock copolymer) micelle was larger than that of PAA-b-PODA-b-PAA (triblock copolymer) micelle. The difference of sizes between these micelles was related to difference of molecular architectures of PAA-b-PODA and PAA-b-PODA-b-PAA. PAA-b-PODA micelle showed morphological transition from disk to spherical shape with elevating temperature. On the contrary, PAA-b-PODA-b-PAA micelle maintained disk-like shape above melting temperature, although enlargement of micelle thickness is caused.

  9. Elastic modulus and flexural strength comparisons of high-impact and traditional denture base acrylic resins

    Directory of Open Access Journals (Sweden)

    Nour M. Ajaj-ALKordy

    2014-01-01

    Conclusion: Within the limitations of this study, it can be concluded that the high-impact acrylic resin is a suitable denture base material for patients with clinical fracture of the acrylic denture.

  10. Tensile bond strength between auto-polymerized acrylic resin and acrylic denture teeth treated with MF-MA solution

    Science.gov (United States)

    2016-01-01

    PURPOSE This study evaluated the effect of chemical surface treatment using methyl formate-methyl acetate (MF-MA) solution on the tensile bond strength between acrylic denture teeth and auto-polymerized acrylic resin. MATERIALS AND METHODS Seventy maxillary central incisor acrylic denture teeth for each of three different brands (Yamahachi New Ace; Major Dent; Cosmo HXL) were embedded with incisal edge downwards in auto-polymerized resin in polyethylene pipes and ground with silicone carbide paper on their ridge lap surfaces. The teeth of each brand were divided into seven groups (n=10): no surface treatment (control group), MF-MA solution at a ratio of 25:75 (v/v) for 15 seconds, 30 seconds, 60 seconds, 120 seconds, 180 seconds, and MMA for 180 seconds. Auto-polymerized acrylic resin (Unifast Trad) was applied to the ground surface and polymerized in a pressure cooker. A tensile strength test was performed with a universal testing machine. Statistical analysis of the results was performed using two-way analysis of variance (ANOVA) and post-hoc Dunnett T3 test (α=.05). RESULTS The surface treatment groups had significantly higher mean tensile bond strengths compared with the control group (P.05), except for the Yamahachi New Ace MF-MA 180-second group (Pteeth with auto-polymerized acrylic resin, for both conventional and cross-linked teeth. PMID:27555897

  11. Lightweight bonded acrylic facing at the Vitra VSL Factory

    Directory of Open Access Journals (Sweden)

    Matthias

    2013-12-01

    Full Text Available Corresponding author: Matthias Michel, E-mail: michel@imagine-structure.eu Acrylic glass is omnipresent in the industrialised world; but as a building material most architects, facade planners and engineers are still unfamiliar with this material. In most cases it is applied as a substitute for glass which leads to inappropriate joints and fixtures. During the years of the path toward the digital era, the authors were in the fortunate position to be involved in several unconventional glass and acrylic glass projects. On the basis of their most recent project, the facade of the Vitra VSL Factory by SANAA Architekten, they describe the development of a facade for which they chose acrylic glass not as a substitute for glass but rather as a conscious material choice. Since the entire facade is it was possible to apply the manufacturing technology of deep-drawing, allowing for very thin wall thicknesses.

  12. Nucleophilic addition of reactive dyes on amidoximated acrylic fabrics.

    Science.gov (United States)

    El-Shishtawy, Reda M; El-Zawahry, Manal M; Abdelghaffar, Fatma; Ahmed, Nahed S E

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% of of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  13. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

    Directory of Open Access Journals (Sweden)

    Reda M. El-Shishtawy

    2014-01-01

    Full Text Available Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% owf of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  14. Ultrasonic velocities, densities, and excess molar volumes of binary mixtures of N,N-dimethyl formamide with methyl acrylate, or ethyl acrylate, or butyl acrylate, or 2-ethyl hexyl acrylate at T = 308.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Kondaiah, M. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India); Sravana Kumar, D. [Dr. V.S. Krishna Govt. Degree College, Visakhapatnam, Andhra Pradesh (India); Sreekanth, K. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India); Krishna Rao, D., E-mail: krdhanekula@yahoo.co.in [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India)

    2011-12-15

    Highlights: > Positive values of V{sub m}{sup E}, indicate dispersion forces between acrylic esters and DMF. > V{sub m}{sup E} values compared with Redlich-Kister polynomial. > Partial molar volumes data conclude that weak interactions exist in the systems. > Measured velocity values compared with theoretical values obtained by polynomials. - Abstract: Ultrasonic velocities, u, densities, {rho}, of binary mixtures of N,N-dimethyl formamide (DMF) with methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), and 2-ethyl hexyl acrylate (EHA), including pure liquids, over the entire composition range have been measured at T = 308.15 K. Using the experimental results, the excess molar volume, V{sub m}{sup E}, partial molar volumes, V-bar {sub m,1}, V-bar{sub m,2}, and excess partial molar volumes, V-bar{sub m,1}{sup E}, V-bar{sub m,2}{sup E} have been calculated. Molecular interactions in the systems have been studied in the light of variation of excess values of calculated properties. The excess properties have been fitted to Redlich-Kister type polynomial and the corresponding standard deviations have been calculated. The positive values of V{sub m}{sup E} indicate the presence of dispersion forces between the DMF and acrylic ester molecules. Further theoretical values of sound velocity in the mixtures have been evaluated using various theories and have been compared with experimental sound velocities to verify the applicability of such theories to the systems studied. Theoretical ultrasonic velocity data have been used to study molecular interactions in the binary systems investigated.

  15. The Evaluation of Water Sorption/Solubility on Various Acrylic Resins

    OpenAIRE

    Tuna, Suleyman Hakan; Keyf, Filiz; Gumus, Hasan Onder; Uzun, Cengiz

    2008-01-01

    Objectives The absorption of water by acrylic resins is a phenomenon of considerable importance since it is accompanied by dimensional changes, a further undesirable effect of absorbed water in acrylic resins to reduce the tensile strength of the material. Solubility is also an important property because it represents the mass of soluble materials from the polymers. Methods Ten acrylic resin-based materials were evaluated: two heat cure acrylic resins (De Trey QC-20, Meliodent Heat Cure) and ...

  16. STUDY ON ACRYLAMIDE-SODIUM ACRYLATE COPOLYMER GELS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Maotang; LI Qian; XU Jiping

    1990-01-01

    Acrylamide-sodium acrylate copolymer hydrogels have been obtained by radiation techniques.Two different methods have been used to introduce -COONa groups into polymer chains of the gels: (1) by partial hydrolysis of acrylamide homopolymer gel; (2) by direct copolymerization and crosslinking of acrylamide and sodium acrylate in aqueous solutions. It was found that the gels obtained in different ways had different properties, the swelling character of the gels obtained by partial hydrolysis were more sensitive to pH of swelling aqueous media. In order to explain these differences,13 C-NMR techniques were used to investigate the sequence distribution of monomer units of both gels.

  17. Triphenylphosphine-Catalyzed Michael Addition of Alcohols to Acrylic Compounds

    Institute of Scientific and Technical Information of China (English)

    LIU, Hai-Ling; JIANG, Huan-Feng; WANG, Yu-Gang

    2007-01-01

    A facile triphenylphosphine-catalyzed Michael addition of alcohols to acrylic compounds was described. The reaction was carried out in open air at refluxing temperature in the presence of 10 mol% PPh3. Michael addition of saturated and unsaturated alcohols to acrylonitrile or acrylates has been examined. The reaction gaveβ-alkoxy derivatives with isolated yields of 5%-79%. PPh3 is cheaper and more stable than those trialkylphosphines previously used for the similar reactions, and the products can be easily separated from the reaction mixture via distillation.

  18. The creep behavior of acrylic denture base resins.

    Science.gov (United States)

    Sadiku, E R; Biotidara, F O

    1996-01-01

    The creep behavior of acrylic dental base resins, at room temperature and at different loading conditions, has been examined. The behaviors of these resins are similar to that of "commercial perspex" at room temperature over a period of 1000 seconds. The pseudo-elastic moduli of the blends of PMMA VC show a significant increase compared with PMMA alone. The addition of the PVC powder to the heat-cured acrylic resin increased the time-dependent elastic modulus. This increase in elastic modulus is advantageous in the production of denture based resins of improv mechanical properties.

  19. Cardiovascular effects of acrylic bone cement in rabbits and cats.

    Science.gov (United States)

    Pelling, D; Butterworth, K R

    1973-06-16

    The cardiovascular responses to forcing acrylic bone cement, Plasticine, or soft paraffin wax into the medullary cavity of the femur have been studied in rabbits and cats. An acute fall in blood pressure, occurring within a few seconds of insertion, was demonstrated with each substance. In a few of the animals the blood pressure response had a second more protracted component and it is suggested that more than one mechanism is involved. The cardiovascular effects that have been observed in man when acrylic cement is used in prosthetic hip surgery also may be due to more than one mechanism. PMID:4714847

  20. Synthesis of acrylic copolymers consisting of multiple amine pendants for dispersing pigment.

    Science.gov (United States)

    Chen, Yu-Min; Hsu, Ru-Siou; Lin, Hsiao-Chu; Chang, Shinn-Jen; Chen, Shih-Chun; Lin, Jiang-Jen

    2009-06-01

    A class of acrylic copolymers with narrow molecular weight distribution from butyl methacrylate and glycidyl methacrylate comonomers via atom transfer radical polymerization was synthesized. Various types of polarities including hydroxyl-amines, glycols, and carboxylic acids were then grafted onto the oxirane side groups. The resultant comb-like copolymers with different polar pendants were tested for homogenizing a representative Yellow pigment in 1,6-hexanediol diacrylate medium. Specifically, the polyacrylates with 1,3-diamine pendants (7-10 multiplicity on each polymer strain) enabled to homogeneously disperse the pigment than the analogous copolymers with hydroxyl or carboxylic acid groups. Ultimately, the pigment dispersion with an average size of ca. 20 nm in diameter, high transmittance and low viscosity was achieved. Furthermore, the pigment dispersion was allowed to UV-cure into a film, and for the first time, the primary structures of the pigment particles (ca. 50 nm in diameter) were observed by transmission electronic microscope. PMID:19364609