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Sample records for low-density polyethylene films

  1. Physical properties of drawn very low density polyethylene films

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.S. [Yeungnam University, Kyongsan (Korea, Republic of); Lee, J.Y. [Korea Institute of Footwear and Leather Technology, Pusan (Korea, Republic of)

    1998-05-01

    Very low density polyethylene (VLDPE) films were prepared by quenching the pressed melt in ice water. The films were drawn with universal testing machine under constant temperature at four different temperatures, 30, 60, 80, and 110 {sup o} C. Thermal, mechanical properties, grossity, and gas permeability of the drawn VLDPE films as a function of draw ratio were investigated to examine their applicability to packaging. The films showed tow melting peaks, i.e., low temperature endotherm (LTE) and high temperature endotherm (HTE). The melting temperatures were increased with the draw ratio and the drawing temperature. The mechanical properties of the VLDPE film drawn at 80 {sup o} C were superior to those drawn at 110 {sup o} C. The grossity and gas permeability of the VLDPE film drawn at 110 {sup o} C were found to be best among the drawn films.

  2. Development of antifungal films based on low-density polyethylene and thyme oil for avocado packaging

    CSIR Research Space (South Africa)

    Kesavan Pillai, Sreejarani

    2015-10-01

    Full Text Available Trilayer low-density polyethylene (LDPE) films were prepared by incorporating varying concentrations of thyme oil, as the antifungal active additive for avocado packaging. A comprehensive thermal, structural, mechanical, and functional...

  3. Study of the effect of gamma irradiation on carbon black loaded low-density polyethylene films

    International Nuclear Information System (INIS)

    Salem, M.A.; Hussein, A.; El-Ahdal, M.A.

    2003-01-01

    The effect of gamma irradiation on the tensile and physico-chemical properties of low-density polyethylene (LDPE) films loaded with different concentrations of carbon black (C.B) has been studied. The results showed that the behavior of the samples during gamma irradiation is complicated and this may be due to scission and the interaction between oxidation and crosslinking processes. The tensile properties are modified by the presence of carbon black. Film sample containing 7% C.B was found to exhibit a nearly stabilized tensile behavior with radiation dose, which allows to use this formulation in packaging for food sterilization and in preservation of weak cobalt-gamma sources. (author)

  4. Effect of degrading yellow oxo-biodegradable low-density polyethylene films to water quality

    Science.gov (United States)

    Requejo, B. A.; Pajarito, B. B.

    2017-05-01

    Polyethylene (PE) contributes largely to plastic wastes that are disposed in aquatic environment as a consequence of its widespread use. In this study, yellow oxo-biodegradable low-density PE films were immersed in deionized water at 50°C for 49 days. Indicators of water quality: pH, oxidation-reduction potential, turbidity, and total dissolved solids (TDS), were monitored at regular intervals. It was observed that pH initially rises and then slowly decreases with time, oxidation-reduction potential decreases then slowly increases with time, turbidity rises above the control at varied rates, and TDS increases abruptly and rises at a hindered rate. Moreover, the films potentially leach out lead chromate. The results imply that degrading oxo-biodegradable LDPE films results to significant reduction of water quality.

  5. Post radiation grafting of vinyl acetate onto low density polyethylene films: preparation and properties of membrane

    International Nuclear Information System (INIS)

    Dessouki, A.M.

    1987-01-01

    Reverse osmosis membranes were prepared by the post radiation grafting of vinyl acetate onto low density polyethylene films. The factors affecting the grafting process such as radiation dose, monomer concentration and temperature on the grafting yield were studied. It was found that the dependence of the grafting rate on radiation intensity and monomer concentration was found to be of 0.64 and 1.4 order, respectively. The activation energy for this grafting system was calculated and found to be 4.45 kcal/mol above 30 0 C. Some properties of the grafted films such as specific electric resistance, water uptake, mechanical properties and thermal and chemical stability were investigated. An improvement in these properties was observed which makes possible the use of these membranes in some practical applications. The use of such membranes for reverse osmosis desalination of saline water was tested. The effect of operating time, degree of grafting and applied pressure on the water flux and salt rejection were determined. The results showed salt rejection percent over 90% and a reasonable water flux. A suitable degree of grafting of the membrane was determined as well as the optimum applied pressure. (author)

  6. Fluorescence properties of dansyl groups covalently bonded to the surface of oxidatively functionalized low-density polyethylene film

    Science.gov (United States)

    Holmes-Farley, S. R.; Whitesides, G. M.

    1985-12-01

    Brief oxidation of low-density polyethylene film with chromic acid in aqueous sulfuric acid introduced carboxylic acid and ketone and/or aldehyde groups onto the surface of the film. The carboxylic acid moieties can be used to attach more complex functionality to the polymer surface. We are developing this surface-functionalized polyethylene (named polyethylene carboxylic acid, PE-CO2H, to emphasize the functional group that dominates its surface properties) as a substrate with which to study problems in organic surface chemistry--especially wetting, polymer surface reconstruction, and adhesion--using physical-organic techniques. This document describes the preparation, characterization, and fluorescence properties of derivatives of PE-CO2H in which the Dansyl (5-dimethylaminonaphthalene-1-sulfonyl) group has been covalently attached by amide links to the surface carbonyl moieties.

  7. Quantitative orientational characterization if low - density polyethylene blow films by x-ray and birefringence

    International Nuclear Information System (INIS)

    Taheri Qazvini, N.; Mohammadi, N.; Ghaffarian, R.; Assempour, H.; Haghighatkish, M.

    2002-01-01

    The effect of two important parameters of film blowing processes, i.e., take-up ration and blow-up ratio, on the overall orientation of low-density blown films have been investigated using birefringence measurements. Furthermore, by combining x-ray diffraction pole figure analysis and birefringence, the White and Spruiell biaxial orientation functions have been determined for aforementioned sample. Within the range of processing condition studied, increasing take-up ratio, increases orientation in both machine and transverse direction. Upon increasing blow-up ratio, orientation in the transverse direction increases and the overall orientation state approaches to equal biaxial one. Characterization of the crystalline regions by pole figure analysis reveals that a and b crystallographic axes preferentially orientate in the film plane and the direction normal to it, respectively. The amorphous regions do not have any preferential orientation

  8. Nanoscale mechanical and tribological properties of fluorocarbon films grafted onto plasma-treated low-density polyethylene surfaces

    International Nuclear Information System (INIS)

    Cheng, Q; Komvopoulos, K

    2012-01-01

    Fluorocarbon (FC) films were grafted onto Ar plasma-treated low-density polyethylene (LDPE) surfaces by plasma polymerization and deposition. The evolution of the surface morphology of the grafted FC films was investigated at different scales with an atomic force microscope. Nanoscale sliding experiments performed with a surface force microscope provided insight into the nanotribological properties of Ar plasma-treated LDPE, with and without grafted FC films, in terms of applied normal load and number of sliding cycles. The observed trends are explained in the context of microstructure models accounting for morphological and structure changes at the LDPE surface due to the effects of plasma treatment (e.g., selective etching of amorphous phase, chain crosslinking and FC film grafting) and surface sliding (e.g., crystalline lamellae alignment along the sliding direction). Nanoindentation experiments elucidated the effect of plasma treatment on surface viscoelasticity and global contact stiffness. The results of this study demonstrate that plasma-assisted grafting of FC films is an effective surface modification method for tuning the nanomechanical/tribological properties of polymers. (paper)

  9. Layer by layer assembly of a biocatalytic packaging film: lactase covalently bound to low-density polyethylene.

    Science.gov (United States)

    Wong, Dana E; Talbert, Joey N; Goddard, Julie M

    2013-06-01

    Active packaging is utilized to overcome limitations of traditional processing to enhance the health, safety, economics, and shelf life of foods. Active packaging employs active components to interact with food constituents to give a desired effect. Herein we describe the development of an active package in which lactase is covalently attached to low-density polyethylene (LDPE) for in-package production of lactose-free dairy products. The specific goal of this work is to increase the total protein content loading onto LDPE using layer by layer (LbL) deposition, alternating polyethylenimine, glutaraldehyde (GL), and lactase, to enhance the overall activity of covalently attached lactase. The films were successfully oxidized via ultraviolet light, functionalized with polyethylenimine and glutaraldehyde, and layered with immobilized purified lactase. The total protein content increased with each additional layer of conjugated lactase, the 5-layer sample reaching up to 1.3 μg/cm2 . However, the increase in total protein did not lend to an increase in overall lactase activity. Calculated apparent Km indicated the affinity of immobilized lactase to substrate remains unchanged when compared to free lactase. Calculated apparent turnover numbers (kcat ) showed with each layer of attached lactase, a decrease in substrate turnover was experienced when compared to free lactase; with a decrease from 128.43 to 4.76 s(-1) for a 5-layer conjugation. Our results indicate that while LbL attachment of lactase to LDPE successfully increases total protein mass of the bulk material, the adverse impact in enzyme efficiency may limit the application of LbL immobilization chemistry for bioactive packaging use. © 2013 Institute of Food Technologists®

  10. Gamma irradiation effects in low density polyethylene

    International Nuclear Information System (INIS)

    Ono, Lilian S.; Scagliusi, Sandra R.; Cardoso, Elisabeth E.L.; Lugao, Ademar B.

    2011-01-01

    Low density polyethylene (LDPE) is obtained from ethylene gas polymerization, being one of the most commercialized polymers due to its versatility and low cost. It's a semi-crystalline polymer, usually inactive at room temperature, capable to attain temperatures within a 80 deg C - 100 deg C range, without changing its physical-chemical properties. LDPE has more resistance when compared to its equivalent High Density Polyethylene (HDPE). LDPE most common applications consist in manufacturing of laboratory materials, general containers, pipes, plastic bags, etc. Gamma radiation is used on polymers in order to modify mechanical and physical-chemical features according to utility purposes. This work aims to the study of gamma (γ) radiation interaction with low density polyethylene to evaluate changes in its physical-chemical properties. Polymer samples were exposed to 5, 10, 15, 20 and 30kGy doses, at room temperature. Samples characterization employed Thermal Analysis, Melt Flow Index, Infrared Spectroscopy and Swelling tests. (author)

  11. Thermal Cracking of Low Density Polyethylene (LDPE) Waste into ...

    African Journals Online (AJOL)

    Waste low density polyethylene film (table water sachets) was converted into solid, liquid oil and gaseous products by thermal process in a self- designed stainless steel laboratory reactor. The waste polymer was completely pyrolized within the temperature range of 474 – 520°C and 2hours reaction time. The solid residue ...

  12. Effect of Die Head Temperature at Compounding Stage on the Degradation of Linear Low Density Polyethylene/Plastic Film Waste Blends after Accelerated Weathering

    Directory of Open Access Journals (Sweden)

    S. M. Al-Salem

    2016-01-01

    Full Text Available Accelerated weathering test was performed on blends of linear low density polyethylene (LLDPE and plastic film waste constituting the following percentages of polyolefin polymers (wt.%: LLDPE (46%, low density polyethylene (LDPE, 51%, high density polyethylene (HDPE, 1%, and polypropylene (PP, 2%. Compounded blends were evaluated for their mechanical and physical (optical properties. The impact of photodegradation on the formulated blends was studied, and loss of mechanical integrity was apparent with respect to both the exposure duration to weathering and waste content. The effect of processing conditions, namely, the die head temperature (DHT of the blown-film assembly used, was investigated in this work. It was witnessed that surpassing the melting point of the blends constituting polymers did not always result in a synergistic behaviour between polymers. This was suspected to be due to the loss of amorphous region that polyolefin polymers get subjected to with UV exposure under weathering conditions and the effect of the plastic waste constituents. The total change in colour (ΔE did not change with respect to DHT or waste content due to rapid change degradation on the material’s surface. Haze (% and light transmission (% decreased with the increase in waste content which was attributed to lack of miscibility between constituting polymers.

  13. Resistance to moist conditions of whey protein isolate and pea starch biodegradable films and low density polyethylene nondegradable films: a comparative study

    Science.gov (United States)

    Mehyar, G. F.; Bawab, A. Al

    2015-10-01

    Biodegradable packaging materials are degraded under the natural environmental conditions. Therefore using them could alleviate the problem of plastics accumulation in nature. For effective replacement of plastics, with biodegradable materials, biodegradable packages should keep their properties under the high relative humidity (RH) conditions. Therefore the objectives of the study were to develop biodegradable packaging material based on whey protein isolate (WPI) and pea starch (PS). To study their mechanical, oxygen barrier and solubility properties under different RHs compared with those of low density polyethylene (LDPE), the most used plastic in packaging. Films of WPI and PS were prepared separately and conditioned at different RH (30-90%) then their properties were studied. At low RHs ( 40% RH. Oxygen permeability of WPI and LDPE did not adversely affected by increasing RH to 65%. Furthermore, WPI and LDPE films had lower degree of hydration at 50% and 90% RH and total soluble matter than PS films. These results suggest that WPI could be successfully replacing LDPE in packaging of moist products.

  14. Large-scale fabrication of linear low density polyethylene/layered double hydroxides composite films with enhanced heat retention, thermal, mechanical, optical and water vapor barrier properties

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Jiazhuo; Zhang, Kun; Zhao, Qinghua [College of Chemistry and Material Science, Shandong Agricultural University, 61 Daizong Street, Tai' an 271018 (China); Wang, Qingguo, E-mail: wqgyyy@126.com [College of Food Science and Engineering, Shandong Agricultural University, 61 Daizong Street, Tai' an 271018 (China); Xu, Jing, E-mail: jiaxu@sdau.edu.cn [College of Chemistry and Material Science, Shandong Agricultural University, 61 Daizong Street, Tai' an 271018 (China)

    2016-11-15

    Novel LDH intercalated with organic aliphatic long-chain anion was large-scale synthesized innovatively by high-energy ball milling in one pot. The linear low density polyethylene (LLDPE)/layered double hydroxides (LDH) composite films with enhanced heat retention, thermal, mechanical, optical and water vapor barrier properties were fabricated by melt blending and blowing process. FT IR, XRD, SEM results show that LDH particles were dispersed uniformly in the LLDPE composite films. Particularly, LLDPE composite film with 1% LDH exhibited the optimal performance among all the composite films with a 60.36% enhancement in the water vapor barrier property and a 45.73 °C increase in the temperature of maximum mass loss rate compared with pure LLDPE film. Furthermore, the improved infrared absorbance (1180–914 cm{sup −1}) of LLDPE/LDH films revealed the significant enhancement of heat retention. Therefore, this study prompts the application of LLDPE/LDH films as agricultural films with superior heat retention. - Graphical abstract: The fabrication process of LLDPE/LDH composite films. - Highlights: • LDH with basal spacing of 4.07 nm was synthesized by high-energy ball milling. • LLDPE composite films with homogeneous LDH dispersion were fabricated. • The properties of LLDPE/LDH composite films were improved. • LLDPE/LDH composite films show superior heat retention property.

  15. Large-scale fabrication of linear low density polyethylene/layered double hydroxides composite films with enhanced heat retention, thermal, mechanical, optical and water vapor barrier properties

    International Nuclear Information System (INIS)

    Xie, Jiazhuo; Zhang, Kun; Zhao, Qinghua; Wang, Qingguo; Xu, Jing

    2016-01-01

    Novel LDH intercalated with organic aliphatic long-chain anion was large-scale synthesized innovatively by high-energy ball milling in one pot. The linear low density polyethylene (LLDPE)/layered double hydroxides (LDH) composite films with enhanced heat retention, thermal, mechanical, optical and water vapor barrier properties were fabricated by melt blending and blowing process. FT IR, XRD, SEM results show that LDH particles were dispersed uniformly in the LLDPE composite films. Particularly, LLDPE composite film with 1% LDH exhibited the optimal performance among all the composite films with a 60.36% enhancement in the water vapor barrier property and a 45.73 °C increase in the temperature of maximum mass loss rate compared with pure LLDPE film. Furthermore, the improved infrared absorbance (1180–914 cm −1 ) of LLDPE/LDH films revealed the significant enhancement of heat retention. Therefore, this study prompts the application of LLDPE/LDH films as agricultural films with superior heat retention. - Graphical abstract: The fabrication process of LLDPE/LDH composite films. - Highlights: • LDH with basal spacing of 4.07 nm was synthesized by high-energy ball milling. • LLDPE composite films with homogeneous LDH dispersion were fabricated. • The properties of LLDPE/LDH composite films were improved. • LLDPE/LDH composite films show superior heat retention property.

  16. Radiation Graft Copolymerization of Butyl methacrylate and Acrylamide onto Low density polyethylene and polypropylene films and its application in wastewater treatment

    International Nuclear Information System (INIS)

    Abdel Ghaffar, A.M.; El-Arnaouty, M.B.; Aboulfotouh, M.E.; Taher, N.H.

    2012-01-01

    Butyl methacrylate and Acrylamide (BMA/AAm) comonomer were grafted onto Low density polyethylene and polypropylene films using direct gamma radiation by grafting technique. The influences of grafting conditions such as solvent, monomer concentration, monomer composition, and irradiation dose on the grafting yield were determined. It was found that, using DMF as a solvent enhanced the copolymerization process. The grafting yield increases with comonomer concentration up to 60 %. . Also it was found that, the degree of grafting of (BMA/AAm) onto LDPE and PP films increases as the AAm content increases till optimum value at (50:50) %. The grafting yield of the comonomer found to be increased with increasing radiation dose. It was observed that the degree of grafting of polyethylene films is higher than that for polypropylene films. Some selected properties of the graft copolymers, such as water uptake and thermal properties determined by using thermogravimetric analysis (TGA) has been carried out. The morphology and structure of grafted films was investigated by using SEM, IR and X-ray diffraction. The improvement in such properties of the prepared copolymers was observed which makes possible uses in some practical applications such as in the removal of some heavy metals from wastewater. It was found that the maximum metal uptake by the copolymer is ordered in the sequence of Cu 2+ > CO 2+ > Ni 2+ ions.

  17. Thermal, mechanical and permeation properties of gamma-irradiated multilayer food packaging films containing a buried layer of recycled low-density polyethylene

    International Nuclear Information System (INIS)

    Chytiri, Stavroula; Goulas, Antonios E.; Riganakos, Kyriakos A.; Kontominas, Michael G.

    2006-01-01

    The effect of gamma radiation (doses 5-60kGy) on the thermal, mechanical and permeation properties, as well as on IR-spectra of experimental five-layer food packaging films were studied. Films contained a middle buried layer of recycled low-density polyethylene (LDPE) comprising 25-50% by weight of the multilayer structure. Representative films containing 100% virgin LDPE as the buried layer were taken as controls. Results showed that the percentage of recycled LDPE in the multilayer structure did not significantly (p<0.05) affect the melting temperature, tensile strength, percent elongation at break, Young's modulus, oxygen, carbon dioxide and water vapour transmission rate values and the IR-spectra of the non-irradiated and irradiated multilayer films. Irradiation (mainly the higher dose of 60kGy) induced certain small, but statistically significant (p<0.05) differences in the mechanical properties of multilayer films (with or without recycled LDPE layer) while no significant differences were observed in the thermal properties and in the gas and water vapour permeability of multilayer films. The above findings are discussed in relation to the good quality of the pre-consumer scrap used in the present study

  18. Using synchrotron-based FT-IR microspectroscopy to study erucamide migration in 50-micron-thick bilayer linear low-density polyethylene and polyolefin plastomer films.

    Science.gov (United States)

    Sankhe, Shilpa Y; Hirt, Douglas E

    2003-01-01

    The diffusion of additives in thick (approximately 500 microns) single layer and multilayer films has been characterized using FT-IR microspectroscopy. The objective of this research was to investigate additive migration and concentration profiles in coextruded multilayer films of industrially relevant thicknesses. In particular, the investigation focused on the migration of an erucamide slip agent in 50-micron-thick coextruded bilayer films of linear low-density polyethylene (LLDPE) and a polyolefin plastomer (POP). Erucamide concentration profiles were successfully mapped using synchrotron-based FT-IR microspectroscopy. The synchrotron radiation helped to achieve a higher spatial resolution for the thin films. Meticulous sample preparation was needed to map the thin film samples. Results with FT-IR microspectroscopy showed that the additive-concentration profiles were relatively uniform across the multilayer-film thickness irrespective of the intended initial additive distribution. For example, a bilayer planned for 1 wt % erucamide in an LLDPE layer and no erucamide in a POP layer showed significant additive migration into the POP layer at the extrusion rates used. FT-IR microspectroscopy results also showed that more erucamide migrated to the surface of a POP layer than an LLDPE layer. Attenuated total reflectance (ATR) FT-IR spectroscopy was used to confirm the time-dependent increase of erucamide surface concentration and that the increase was more pronounced at the surface of the POP layers.

  19. Volatile and non-volatile radiolysis products in irradiated multilayer coextruded food-packaging films containing a buried layer of recycled low-density polyethylene.

    Science.gov (United States)

    Chytiri, S; Goulas, A E; Badeka, A; Riganakos, K A; Kontominas, M G

    2005-12-01

    The effects of gamma-irradiation (5-60 kGy) on radiolysis products and sensory changes of experimental five-layer food-packaging films were determined. Films contained a middle buried layer of recycled low-density polyethylene (LDPE) comprising 25-50% by weight (bw) of the multilayer structure. Respective films containing 100% virgin LDPE as the buried layer were used as controls. Under realistic polymer/food simulant contact conditions during irradiation, a large number of primary and secondary radiolysis products (hydrocarbons, aldehydes, ketones, alcohols, carboxylic acids) were produced. These compounds were detected in the food simulant after contact with all films tested, even at the lower absorbed doses of 5 and 10 kGy (approved doses for food preservation). The type and concentration of radiolysis products increased progressively with increasing dose. Generally, there were no significant differences in radiolysis products between samples containing a buried layer of recycled LDPE and those containing virgin LDPE (all absorbed doses), indicating the good barrier properties of external virgin polymer layers. Volatile and non-volatile compounds produced during irradiation affected the sensory properties of potable water after contact with packaging films. Taste transfer to water was observed mainly at higher doses and was more noticeable for multilayer structures containing recycled LDPE, even though differences were slight.

  20. Radiolysis products and sensory properties of electron-beam-irradiated high-barrier food-packaging films containing a buried layer of recycled low-density polyethylene.

    Science.gov (United States)

    Chytiri, S D; Badeka, A V; Riganakos, K A; Kontominas, M G

    2010-04-01

    The aim was to study the effect of electron-beam irradiation on the production of radiolysis products and sensory changes in experimental high-barrier packaging films composed of polyamide (PA), ethylene-vinyl alcohol (EVOH) and low-density polyethylene (LDPE). Films contained a middle buried layer of recycled LDPE, while films containing 100% virgin LDPE as the middle buried layer were taken as controls. Irradiation doses ranged between zero and 60 kGy. Generally, a large number of radiolysis products were produced during electron-beam irradiation, even at the lower absorbed doses of 5 and 10 kGy (approved doses for food 'cold pasteurization'). The quantity of radiolysis products increased with irradiation dose. There were no significant differences in radiolysis products identified between samples containing a recycled layer of LDPE and those containing virgin LDPE (all absorbed doses), indicating the 'functional barrier' properties of external virgin polymer layers. Sensory properties (mainly taste) of potable water were affected after contact with irradiated as low as 5 kGy packaging films. This effect increased with increasing irradiation dose.

  1. Biodegradation of films of low density polyethylene (LDPE, poly(hydroxibutyrate-co-valerate (PHBV, and LDPE/PHBV (70/30 blend with Paecilomyces variotii

    Directory of Open Access Journals (Sweden)

    Thayse Marques Passos

    2015-02-01

    Full Text Available The increased consumption of plastics in the world has been a subject of great concern and special attention by the scientific community. The aim is to promote development of materials that are biodegradable in a shorter time upon disposal in the environment. The most used synthetic plastics are difficult to biodegrade because they are made of long hydrocarbon chains, such as polyethylene (PE, polypropylene (PP, poly(vinyl chloride (PVC, which are hydrophobic and resistant to the action of microbial enzymes. The use of alternative materials (natural polyesters can minimize the harm to dumps and landfills upon their disposal, because they are susceptible to the action of microorganisms. In this study we evaluated the biodegradation/biodeterioration of PHBV (poly(3-hydroxybutyrate-co-hydroxyvalerate films, LDPE (low density polyethylene and the blend of LDPE/PHBV (70/30 by the fungus Paecilomyces variotii, using different methods: optical microscopy (OM, scanning electronic microscopy (SEM and Fourier Transform Infrared spectroscopy (FTIR.

  2. Dielectric properties: A gateway to antibacterial assay-A case study of low-density polyethylene/chitosan composite films.

    Digital Repository Service at National Institute of Oceanography (India)

    Sunilkumar, M.; Gafoor, A.A.; Anas, A.; Haseena, A.P.; Sujith, A.

    anhydride and dicumyl peroxide were used as a coupling agent and a free radical initiator, respectively. The dielectric properties of the composite films were studied as a function of chitosan loading, presence of plasticizer and variable applied frequency...

  3. Thermoluminescence glow curves of irradiated PMMA and low density polyethylene

    International Nuclear Information System (INIS)

    Matsuda, Koji; Nakase, Yoshiaki; Kumakiri, Yasuhito; Tsuji, Yoshio.

    1985-03-01

    Light emission from polymers is observed when polymers preirradiated with ionizing radiation at low temperature are heated gradually. The light emission is supposedly resulted from recombination of electrons with active centers produced in polymers or from some other processes involving charge transfer, but no definite explanation has been given at present on the thermoluminescent centers. This report describes our studies on the effects of impurities contained in polymers and pressure of ambient gases on the thermoluminescent glow curve of PMMA and low density polyethylene, which are often used for plastic film dosimeters. In the glow curve of PMMA, only one peak was observed at 110 K in an H 2 or He atmosphere at 760 Torr, but the intensity of the peak decreased with decreasing the H 2 or He gas pressure. At 10 -5 Torr H 2 or He atmosphere the peak disappered, and two sharp peaks appeared in the temperature range from 200 to 250 K. On the other hand, in the glow curve of low density polyethylene, three peaks were observed at 120 K, 180 K and 250 K in the presence of H 2 or He gas at 760 Torr. The effects of pressure of ambient gases and impurities in the polyethylene on these peaks indicate that the peak at 120 K is due to luminescent center produced on the surface or just below the surface of the matrix by collision of excited atoms or molecules of gases with polymer molecules, the peak at 120 K is originated from impurities in the matrix, and the peak at 250 0 K corresponds to luminescent center produced in polyethylene matrix. (author)

  4. Development of indigenous linear low-density polyethylene film and other related techniques for heavy-load balloons in India

    Science.gov (United States)

    Redkar, R. T.

    1993-02-01

    A new grade of balloon film extruded out of LLDPE resin with Butene as comonomer and Cold Brittle Point (CBP) at -88°C was extruded and successfully flight tested with a 25 micron single shell 53,000 Cu.M. balloon carrying 330 Kg. payload to 33 Km. altitude. We have also produced superior LLDPE film out of Dowlex 2045 Dow Chemicals resin with Octene as comonomer, which has the cold brittle point lower than -90°C and superior mechanical properties at low temperatures. A high pressure hydrogen filling system capable of delivering 2200 Cu.Ft. of hydrogen per minute has been commissioned and successfully utilised in 11 flights. With this new filling system, the inflation time is drastically reduced by over 50% thereby reducing the duration of pre-launch stresses on the ground bubble. After the acceptance of our revised design criteria for balloons to be flown from equatorial latitudes by M/s.Winzen International Inc., U.S.A., 41 flights have been made, out of which 36 have been successful giving us a success record of 88%. Out of the 5 failures, 3 have been float failures with gross inflations exceeding 1950 kg, for which launch spool damage is a suspect. To reduce the spool damage, the shell thickness of the subsequent balloon was increased to 20.32 microns from 17.78 microns and the flight was a success. For further reducing the possibility of launch spool damage, a larger diameter spool is being designed.

  5. Microbial biodegradable potato starch based low density polyethylene

    African Journals Online (AJOL)

    USER

    2010-06-28

    Jun 28, 2010 ... Key words: Low density polyethylene, fungi, biodegradable polymer, Pseudomonas aeruginosa. ... particle such as CO2 or water by microorganism's activities. ... package and production of bags, composites and agricultural.

  6. On the mechanism of charge transport in low density polyethylene

    Science.gov (United States)

    Upadhyay, Avnish K.; Reddy, C. C.

    2017-08-01

    Polyethylene based polymeric insulators, are being increasingly used in the power industry for their inherent advantages over conventional insulation materials. Specifically, modern power cables are almost made with these materials, replacing the mass-impregnated oil-paper cable technology. However, for ultra-high dc voltage applications, the use of these polymeric cables is hindered by ununderstood charge transport and accumulation. The conventional conduction mechanisms (Pool-Frenkel, Schottky, etc.) fail to track high-field charge transport in low density polyethylene, which is semi-crystalline in nature. Until now, attention was devoted mainly to the amorphous region of the material. In this paper, authors propose a novel mechanism for conduction in low density polyethylene, which could successfully track experimental results. As an implication, a novel, substantial relationship is established for electrical conductivity that could be effectively used for understanding conduction and breakdown in polyethylene, which is vital for successful development of ultra-high voltage dc cables.

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

    Science.gov (United States)

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

    2018-05-01

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

  8. Flow and breakup in extension of low-density polyethylene

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Fasano, Andrea

    2018-01-01

    The breakup during the extension of a low-density polyethylene Lupolen 1840D, as observed experimentally by Burghelea et al. (J Non-Newt Fluid Mech 166:1198–1209 2011), was investigated. This was observed during the extension of an circular cylinder with radius R0 = 4 mm and length L0 = 5mm....... The sample was attached to two flat end plates, separated exponentially in time to extend the samples. A numerical method based on a Lagrangian kinematics description in a continuum mechanical framework was used to calculate the extension of an initially cylindrically shaped sample with and without small...... the error bars as reported experimentally by Burghelea et al. (J Non-Newt Fluid Mech 166:1198–1209 2011). At low extensional rates, the measurements were considerably above the calculated ones. A very small relative suppression in the surface (0.1%) was required to achieve an agreement with all measurements...

  9. Effect of previous chilling storage on quality loss in frozen (–20 °C sierra (Scomberomorus sierra muscle packed with a low-density polyethylene film containing butylated hydroxytoluene

    Directory of Open Access Journals (Sweden)

    Herlinda Soto-Valdez

    2015-03-01

    Full Text Available Rancidity development during frozen storage (–20 °C of sierra fish (Scomberomorus sierra was studied. Fillets were packed in low-density polyethylene films with and without butylated hydroxytoluene added (BHT-LDPE and LDPE respectively. Fillets stored with no package were used as control. Special attention was given to the effect of previous ice storage (0, 3, 6, 9 and 15 days on the quality of the frozen fish. Physical (pH and texture and chemical (peroxide value, PV and thiobarbituric acid index, TBA-i analyses were carried out. Lipid oxidation increased with ice storage time in fish muscle without film packing, being greater than the film packed muscle (with and without antioxidant. An effect of previous ice storage time was observed on the frozen product (in all treatments. However, fish muscle with film packing containing antioxidant showed less lipid deterioration. Under the conditions applied in this study, the plastic films with antioxidant prevented the lipids oxidation during the cold handling of the sierra muscle.

  10. Ultralow energy ion beam surface modification of low density polyethylene.

    Science.gov (United States)

    Shenton, Martyn J; Bradley, James W; van den Berg, Jaap A; Armour, David G; Stevens, Gary C

    2005-12-01

    Ultralow energy Ar+ and O+ ion beam irradiation of low density polyethylene has been carried out under controlled dose and monoenergetic conditions. XPS of Ar+-treated surfaces exposed to ambient atmosphere show that the bombardment of 50 eV Ar+ ions at a total dose of 10(16) cm(-2) gives rise to very reactive surfaces with oxygen incorporation at about 50% of the species present in the upper surface layer. Using pure O+ beam irradiation, comparatively low O incorporation is achieved without exposure to atmosphere (approximately 13% O in the upper surface). However, if the surface is activated by Ar+ pretreatment, then large oxygen contents can be achieved under subsequent O+ irradiation (up to 48% O). The results show that for very low energy (20 eV) oxygen ions there is a dose threshold of about 5 x 10(15) cm(-2) before surface oxygen incorporation is observed. It appears that, for both Ar+ and O+ ions in this regime, the degree of surface modification is only very weakly dependent on the ion energy. The results suggest that in the nonequilibrium plasma treatment of polymers, where the ion flux is typically 10(18) m(-2) s(-1), low energy ions (<50 eV) may be responsible for surface chemical modification.

  11. Effect of Aspergillus versicolor strain JASS1 on low density polyethylene degradation

    Science.gov (United States)

    Gajendiran, A.; Subramani, S.; Abraham, J.

    2017-11-01

    Low density polyethylene (LDPE) waste disposal remains one of the major environmental concerns faced by the world today. In past decades, major focus has been given to enhance the biodegradation of LDPE by microbial species. In this present study, Aspergillus versicolor with the ability to degrade LDPE was isolated from municipal landfill area using enrichment technique. Based on 18S rRNA gene sequencing confirmed its identity as Aspergillus versicolor. The biodegradation study was carried out for 90 d in M1 medium. The degradation behaviour of LDPE films by Aspergillus versicolor strain JASS1 were confirmed by weight loss, CO2 evolution, Scanning electron microscopy (SEM) analysis, Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) technique. From current investigation, it can be concluded that our isolated strain JASS1 had the potential to degrade LDPE films and it can be useful in solving the problem caused by polyethylene in the environment.

  12. Modification of low density polyethylene, isostatic polypropylene and their blends by gamma radiation

    International Nuclear Information System (INIS)

    Santos Rosa, D. dos

    1991-01-01

    The effects of the gamma radiation (of a 60 Co source), over low density polyethylene, isostatic polypropylene and their blends of low density polyethylene / polypropylene were studied. The structures modifications were attended by infrared spectrometry (IV), differential scanning calorimeter (DSC), strain-strain measurement, density measurement and scanning electron microscope (SEM). (author)

  13. Homocomposites of chopped fluorinated polyethylene fiber with low-density polyethylene matrix

    International Nuclear Information System (INIS)

    Maity, J.; Jacob, C.; Das, C.K.; Alam, S.; Singh, R.P.

    2008-01-01

    Conventional composites are generally prepared by adding reinforcing agent to a matrix and the matrix wherein the reinforcing agents are different in chemical composition with the later having superior mechanical properties. This work presents the preparation and properties of homocomposites consisting of a low-density polyethylene (LDPE) matrix and an ultra high molecular weight polyethylene (UHMWPE) fiber reinforcing phase. Direct fluorination is an important surface modification process by which only a thin upper layer is modified, the bulk properties of the polymer remaining unchanged. In this work, surface fluorination of UHMWPE fiber was done and then fiber characterization was performed. It was observed that after fluorination the fiber surface became rough. Composites were then prepared using both fluorinated and non-fluorinated polyethylene fiber with a low-density polyethylene (LDPE) matrix to prepare single polymer composites. It was found that the thermal stability and mechanical properties were improved for fluorinated fiber composites. X-ray diffraction (XRD) analysis showed that the crystallinity of the composites increased and it is maximum for fluorinated fiber composites. Tensile strength (TS) and modulus also increased while elongation at break (EB) decreased for fiber composites and was a maximum for fluorinated fiber composites. Scanning electron microscopic analysis indicates that that the distribution of fiber into the matrix is homogeneous. It also indicates the better adhesion between the matrix and the reinforcing agent for modified fiber composites. We also did surface fluorination of the prepared composites and base polymer for knowing its application to different fields such as printability wettability, etc. To determine the various properties such as printability, wettability and adhesion properties, contact angle measurement was done. It was observed that the surface energies of surface modified composites and base polymer increases

  14. Biodegradation of low density polyethylene (LDPE) by a new ...

    African Journals Online (AJOL)

    aghomotsegin

    The microbial degradation of LDPE was also analyzed by the change in pH of the culture ... The generation of biodegradable polyethylene requires ...... Use of scanning electron microscope for the examination of actinomycetes. J. Gen. Microbiol. 48:171-177. Yamada-Onodera K, Mukumoto H, Katsuyaya Y, Saiganji A, Tani ...

  15. Linear low density polyethylene (LLDPE) and lamellar zirconium phosphate (Zr P) composites: morphology and mechanical properties

    International Nuclear Information System (INIS)

    Silva, Daniela F.; Mandes, Luis C.; Lino, Adan S.

    2011-01-01

    Composites of linear low density polyethylene (LLDPE) and zirconium phosphate (ZrP) were prepared by extrusion in the molten state, containing 2 (w%) of the lamellar filler. The filler was previously synthesized by direct precipitation method and characterized. After processing, the composite and the pure virgin polymer were molded by compression in order to obtain films of 1 mm thick which were characterized by X-ray diffraction at high angle (WAXD), stress-strain mechanical analysis and scanning electron microscopy (SEM). The WAXD and SEM analysis showed that there was no intercalation of LLDPE in zirconium phosphate, possibly due to the fact that the layers do not have spacing enough to allow the intercalation of polymer chains in the galleries of the filler and thus allow the exfoliation. (author)

  16. Oil-Impregnated Polyethylene Films

    Science.gov (United States)

    Mukherjee, Ranit; Habibi, Mohammad; Rashed, Ziad; Berbert, Otacilio; Shi, Shawn; Boreyko, Jonathan

    2017-11-01

    Slippery liquid-infused porous surfaces (SLIPS) minimize the contact angle hysteresis of a wide range of liquids and aqueous food products. Although hydrophobic polymers are often used as the porous substrate for SLIPS, the choice of polymer has been limited to silicone-based or fluorine-based materials. Hydrocarbon-based polymers, such as polyethylene, are cost effective and widely used in food packaging applications where SLIPS would be highly desirable. However, to date there have been no reports on using polyethylene as a SLIPS substrate, as it is considered highly impermeable. Here, we show that thin films of low-density polyethylene can be stably impregnated with carbon-based oils without requiring any surface modification. Wicking tests reveal that oils with sufficient chemical compatibility follow Washburn's equation. The nanometric effective pore size of the polyethylene does result in a very low wicking speed, but by using micro-thin films and a drawdown coater, impregnation can still be completed in under one second. The oil-impregnated polyethylene films promoted ultra-slippery behavior for water, ketchup, and yogurt while remaining durable even after being submerged in ketchup for over one month. This work was supported by Bemis North America (AT-23981).

  17. Potential of bacteria isolated from landfill soil in degrading low density polyethylene plastic

    Science.gov (United States)

    Munir, E.; Sipayung, F. C.; Priyani, N.; Suryanto, D.

    2018-03-01

    Plastic is an important material and used for many purposes. It is returned to the environment as a waste which is recently considered as the second largest solid waste. The persistency of plastic in the environment has been attracted researchers from a different point of view. The study of the degradation of plastic using bacteria isolated from local landfill soil was conducted. Low density polyethylene (LDPE) plastic was used as tested material. Potential isolates were obtained by culturing the candidates in mineral salt medium broth containing LDPE powder. Two of ten exhibited better growth response in the selection media and were used in degradation study. Results showed that isolate SP2 and SP4 reduced the weight of LDPE film significantly to a weight loss of 10.16% and 12.06%, respectively after four weeks of incubation. Scanning electron micrograph analyses showed the surface of LDPE changed compared to the untreated film. It looked rough and cracked, and bacteria cells attached to the surface was also noticed. Fourier transform infrared spectroscopy analyses confirmed the degradation of LDPE film. These results indicated that bacteria isolated from landfill might play an important role in degrading plastic material in the landfill.

  18. Degradation behavior of linear low density polyethylene by ultraviolet radiation exposition for agricultural applications

    Energy Technology Data Exchange (ETDEWEB)

    Poveda, Patricia N.S.; Silva, Leonardo G.A., E-mail: lgasilva@ipen.br, E-mail: patricianegrini@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ciro, Rosemeire, E-mail: rosemeireciro@msn.com [Faculdades Oswaldo Cruz (FOC), Sao Paulo, SP (Brazil); Viana, Hamilton M., E-mail: hmviana@gmail.com [Centro Universitario Fundacao de Santo Andre (FSA/FAENG), Santo Andre, SP (Brazil)

    2013-07-01

    Polyethylene is the most important polymer used in agricultural applications. Polymers are susceptible to changes in their chemical structures that affect their mechanical properties under weather condition. In Polyethylene, photo-oxidation can occur because of impurities or chromophore groups (catalytic residue, mineral fillers, some commercial additives as stabilizers, lubricants, plasticizers, etc.). The critical ageing factors for greenhouse built with LDPE film are: total solar radiation, air temperature, relative humidity, mechanical stress, agrochemicals, air pollution, and combinations of these factors. Exposure of plastics to UV radiation causes a loss in their mechanical properties and/or change in appearance, including reduced ductility, color changes, yellowing and cracking. Additives are added to plastics to enhance the durability of the final product. Today, there are several additive systems (light stabilizers) developed to work according to resin, final application, type of cultivation, and other characteristics. The main types of light stabilizers are: UV absorbers, quenchers and free radicals scavengers. In addition to the conventional organic additives, some inorganic additives were obtained recently with the development of nanotechnology. This study evaluates the different additive systems (HALS, NPCC, nZnO and nTiO{sub 2}), applied 0.25% (in weight) in LLDPE. The samples were mixed by high rotation homogenizer and extrusion. Later, the samples were molded by injection and aged in QUV-B simulating 6 months of exposure to weather. Tests of FT-IR and tensile strength comparing to the non-aged samples were carried out in order to evaluate the performance of several additive systems concerning the degradation behavior of linear low density polyethylene. (author)

  19. Degradation behavior of linear low density polyethylene by ultraviolet radiation exposition for agricultural applications

    International Nuclear Information System (INIS)

    Poveda, Patricia N.S.; Silva, Leonardo G.A.; Ciro, Rosemeire; Viana, Hamilton M.

    2013-01-01

    Polyethylene is the most important polymer used in agricultural applications. Polymers are susceptible to changes in their chemical structures that affect their mechanical properties under weather condition. In Polyethylene, photo-oxidation can occur because of impurities or chromophore groups (catalytic residue, mineral fillers, some commercial additives as stabilizers, lubricants, plasticizers, etc.). The critical ageing factors for greenhouse built with LDPE film are: total solar radiation, air temperature, relative humidity, mechanical stress, agrochemicals, air pollution, and combinations of these factors. Exposure of plastics to UV radiation causes a loss in their mechanical properties and/or change in appearance, including reduced ductility, color changes, yellowing and cracking. Additives are added to plastics to enhance the durability of the final product. Today, there are several additive systems (light stabilizers) developed to work according to resin, final application, type of cultivation, and other characteristics. The main types of light stabilizers are: UV absorbers, quenchers and free radicals scavengers. In addition to the conventional organic additives, some inorganic additives were obtained recently with the development of nanotechnology. This study evaluates the different additive systems (HALS, NPCC, nZnO and nTiO 2 ), applied 0.25% (in weight) in LLDPE. The samples were mixed by high rotation homogenizer and extrusion. Later, the samples were molded by injection and aged in QUV-B simulating 6 months of exposure to weather. Tests of FT-IR and tensile strength comparing to the non-aged samples were carried out in order to evaluate the performance of several additive systems concerning the degradation behavior of linear low density polyethylene. (author)

  20. Estudo do reprocessamento de polietileno de baixa densidade (PEBD reciclado do processamento de extrusão de filmes tubulares Study of the reprocessing of low density polyethylene (LDPE recycled from extruded blown films

    Directory of Open Access Journals (Sweden)

    Vinicius Pistor

    2010-01-01

    Full Text Available O mercado de reciclagem para os polímeros termoplásticos encontra-se atualmente em acentuada ascensão. Os materiais reciclados são vistos como materiais de propriedades inferiores em relação ao material virgem. O presente trabalho avaliou as características viscoelásticas e térmicas do polietileno de baixa densidade (PEBD reciclado. As amostras foram reprocessadas até dez vezes em condições extremas de processamento (300 °C/80 rpm em uma extrusora monorosca, a fim de avaliar modificações estruturais nas suas propriedades. Foram realizadas análises de reometria oscilatória de placas paralelas e calorimetria exploratória de varredura (DSC. A partir das análises de reometria oscilatória foram calculados espectros de relaxação e retardação pelo programa de regularização não-linear (NLREG e através das análises de DSC no primeiro aquecimento foram calculados os parâmetros cinéticos pelos métodos de Avrami e Freeman-Carroll. Os resultados do estudo reológico demonstraram que as amostras reprocessadas acima de quatro vezes apresentaram aumento da viscosidade complexa e dos módulos de armazenamento e perda, além de fenômenos de relaxação e retardação mais largos. Entretanto, os termogramas de DSC e os parâmetros cinéticos de fusão demonstraram que o PEBD estudado manteve sua estabilidade térmica, independentemente da modificação de suas características viscoelásticas.The recycling market of thermoplastic polymers is currently in a sharp increase. Recycled materials are regarded as having inferior properties compared to the virgin material. Here we investigated the viscoelastic and thermal properties of the recycled low density polyethylene (LDPE. The samples were reprocessed up to ten times under extreme processing conditions (300 °C/80 rpm in a single screw extruder in order to evaluate structural changes in their properties. Analyses were performed in an oscillatory rheometer with parallel plates and in

  1. Mechanical and electrical properties of low density polyethylene filled with carbon nanotubes

    International Nuclear Information System (INIS)

    Sabet, Maziyar; Soleimani, Hassan

    2014-01-01

    Carbon nanotubes (CNTs) reveal outstanding electrical and mechanical properties in addition to nanometer scale diameter and high aspect ratio, consequently, making it an ideal reinforcing agent for high strength polymer composites. Low density polyethylene (LDPE)/CNT composites were prepared via melt compounding. Mechanical and electrical properties of (LDPE)/CNT composites with different CNT contents were studied in this research

  2. Modeling of branching density and branching distribution in low-density polyethylene polymerization

    NARCIS (Netherlands)

    Kim, D.M.; Iedema, P.D.

    2008-01-01

    Low-density polyethylene (ldPE) is a general purpose polymer with various applications. By this reason, many publications can be found on the ldPE polymerization modeling. However, scission reaction and branching distribution are only recently considered in the modeling studies due to difficulties

  3. A new look at extensional rheology of low-density polyethylene

    DEFF Research Database (Denmark)

    Huang, Qian; Mangnus, Marc; Alvarez, Nicolas J.

    2016-01-01

    The nonlinear rheology of three selected commercial low-density polyethylenes (LDPE) is measured in uniaxial extensional flow. The measurements are performed using three different devices including an extensional viscosity fixture (EVF), a homemade filament stretching rheometer (DTU-FSR) and a co...

  4. Determination of charge carrier mobility in doped low density polyethylene using DC transients

    DEFF Research Database (Denmark)

    Khalil, M.Salah; Henk, Peter O; Henriksen, Mogens

    1989-01-01

    Charge carrier mobility was determined for plain and doped low-density polyethylene (LDPE) using DC transient currents. Barium titanate was used as a strongly polar dopant and titanium dioxide as a semiconductor dopant. The values of the mobility obtained were on the order of 10-10 cm2 v-1 s-1...

  5. An Investigation on Rheology of Peroxide Cross-linking of Low Density Polyethylene

    DEFF Research Database (Denmark)

    Ghasemi, Ismaeil; Rasmussen, Henrik K.; Szabo, Peter

    2005-01-01

    One of the most important post-reactor modifications of polyethylene is cross-linking. It improves some properties of polyethylene such as environmental stress cracking resistance, chemical and abrasion resistance, and service temperature. In this study, the effect of peroxide cross-linking on th......One of the most important post-reactor modifications of polyethylene is cross-linking. It improves some properties of polyethylene such as environmental stress cracking resistance, chemical and abrasion resistance, and service temperature. In this study, the effect of peroxide cross......-linking on the rheological behaviour of low density polyethylene was investigated by using a combination of creep test and differential scanning calorimeter (DSC) in isotherm condition. The used peroxide was di-cumyl peroxide and its concentration was 2 wt%. The experiments were carried out at 150,160, and 170 degrees C...

  6. Biodegradation of low-density polyethylene (LDPE) by isolated fungi in solid waste medium

    International Nuclear Information System (INIS)

    Zahra, Sahebnazar; Abbas, Shojaosadati Seyed; Mahsa, Mohammad-Taheri; Mohsen, Nosrati

    2010-01-01

    In this study, biodegradation of low-density polyethylene (LDPE) by isolated landfill-source fungi was evaluated in a controlled solid waste medium. The fungi, including Aspergillus fumigatus, Aspergillus terreus and Fusarium solani, were isolated from samples taken from an aerobic aged municipal landfill in Tehran. These fungi could degrade LDPE via the formation of a biofilm in a submerged medium. In the sterilized solid waste medium, LPDE films were buried for 100 days in a 1-L flask containing 400 g sterile solid waste raw materials at 28 deg. C. Each fungus was added to a separate flask. The moisture content and pH of the media were maintained at the optimal levels for each fungus. Photo-oxidation (25 days under UV-irradiation) was used as a pretreatment of the LDPE samples. The progress of the process was monitored by measurement of total organic carbon (TOC), pH, temperature and moisture. The results obtained from monitoring the process using isolated fungi under sterile conditions indicate that these fungi are able to grow in solid waste medium. The results of FT-IR and SEM analyses show that A. terreus and A. fumigatus, despite the availability of other organic carbon of materials, could utilize LDPE as carbon source. While there has been much research in the field of LDPE biodegradation under solid conditions, this is the first report of degradation of LDPE by A. fumigatus.

  7. Low-pressure plasma enhanced immobilization of chitosan on low-density polyethylene for bio-medical applications

    International Nuclear Information System (INIS)

    Pandiyaraj, K. Navaneetha; Ferraria, Ana Maria; Rego, Ana Maria Botelho do; Deshmukh, Rajendra R.; Su, Pi-Guey; Halleluyah, Jr. Mercy; Halim, Ahmad Sukari

    2015-01-01

    Highlights: • Acrylic acid (AAc) was grafted on LDPE film by in situ plasma polymerization. • Molecules of PEG and chitosan were immobilized on AAc grafted LDPE films. • Surface modified LDPE exhibits excellent hydrophilic property. • Surface modified LDPE resist the adsorption of protein and adhesion of platelets. - Abstract: With the aim of improving blood compatibility of low density polyethylene (LDPE) films, an effective low-pressure plasma technology was employed to functionalize the LDPE film surfaces through in-situ grafting of acrylic acid (AAc). Subsequently, the molecules of poly(ethylene glycol) (PEG) and chitosan (CHI) were immobilized on the surface of grafted LDPE films. The unmodified and modified LDPE films were analyzed using various characterization techniques such as contact angle, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray photo electron spectroscopy (XPS) to understand the changes in surface properties such as hydrophilicity, surface topography and chemical composition, respectively. Furthermore, LDPE films have been subjected to an ageing process to determine the durability of the plasma assisted surface modification. The blood compatibility of the surface modified LDPE films was confirmed by in vitro tests. It was found that surface modified LDPE films show better hydrophilic behavior compared with the unmodified one. FTIR and XPS results confirm the successful immobilization of CHI on the surface of LDPE films. LDPE films showed marked morphological changes after grafting of AAc, PEG and CHI which were confirmed through AFM imaging. The in vitro blood compatibility tests have clearly demonstrated that CHI immobilized LDPE films exhibit remarkable anti thrombogenic nature compared with other modified films. Surface modified LDPE films through low-pressure plasma technique could be adequate for biomedical implants such as artificial skin substrates, urethral catheters or cardiac stents

  8. Low-pressure plasma enhanced immobilization of chitosan on low-density polyethylene for bio-medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Pandiyaraj, K. Navaneetha, E-mail: dr.knpr@gmail.com [Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, L& T by pass, Chinniyam Palayam (post), Coimbatore, 641062 (India); Ferraria, Ana Maria; Rego, Ana Maria Botelho do [Centro de Química- Física Molecular and Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, University of Lisbon (Portugal); Deshmukh, Rajendra R. [Department of Physics, Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Su, Pi-Guey [Department of Chemistry, Chinese Culture University, Taipei 111, Taiwan (China); Halleluyah, Jr. Mercy; Halim, Ahmad Sukari [Reconstructive Science Unit, School of Medical Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2015-02-15

    Highlights: • Acrylic acid (AAc) was grafted on LDPE film by in situ plasma polymerization. • Molecules of PEG and chitosan were immobilized on AAc grafted LDPE films. • Surface modified LDPE exhibits excellent hydrophilic property. • Surface modified LDPE resist the adsorption of protein and adhesion of platelets. - Abstract: With the aim of improving blood compatibility of low density polyethylene (LDPE) films, an effective low-pressure plasma technology was employed to functionalize the LDPE film surfaces through in-situ grafting of acrylic acid (AAc). Subsequently, the molecules of poly(ethylene glycol) (PEG) and chitosan (CHI) were immobilized on the surface of grafted LDPE films. The unmodified and modified LDPE films were analyzed using various characterization techniques such as contact angle, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray photo electron spectroscopy (XPS) to understand the changes in surface properties such as hydrophilicity, surface topography and chemical composition, respectively. Furthermore, LDPE films have been subjected to an ageing process to determine the durability of the plasma assisted surface modification. The blood compatibility of the surface modified LDPE films was confirmed by in vitro tests. It was found that surface modified LDPE films show better hydrophilic behavior compared with the unmodified one. FTIR and XPS results confirm the successful immobilization of CHI on the surface of LDPE films. LDPE films showed marked morphological changes after grafting of AAc, PEG and CHI which were confirmed through AFM imaging. The in vitro blood compatibility tests have clearly demonstrated that CHI immobilized LDPE films exhibit remarkable anti thrombogenic nature compared with other modified films. Surface modified LDPE films through low-pressure plasma technique could be adequate for biomedical implants such as artificial skin substrates, urethral catheters or cardiac stents

  9. Degradation of low-density polyethylene in the presence of water and deuterium oxide

    International Nuclear Information System (INIS)

    Sedgwick, R.D.; Al-Sultan, Y.Y.; Abushihada, A.M.

    1981-01-01

    The degradation of low-density polyethylene in the presence of water as the degradative agent was studied at a temperature of 450 0 C and a pressure greater than 160 atm. The experimental work was conducted in an autoclave of 333-mL capacity. The results indicate the presence of paraffins, olefines, dienes, and aromatics in the degradation products. The occurrence of aromatics in the products demonstrates the importance of this degradation procedure for obtaining these valuable materials. The present work (Part 1) is believed to be the first publication to discuss the production of aromatics from polyethylenes degradation

  10. Preliminary characterization in the development of the nano composite low density polyethylene with attapulgite clay

    International Nuclear Information System (INIS)

    Domingos, Luanda G.; Rego, Jose K.M.A. do; Ito, Edson N.; Acchar, Wilson

    2011-01-01

    The aim of this study was a preliminary study of the physical, thermal and rheological properties of the materials to be used in the development of nano composite low density polyethylene (LDPE) with Brazilian attapulgite clay (ATP), with and without the use of a compatibilizing agent interfacial, polyethylene grafted with maleic anhydride (PE-g-MAH). The materials were characterized by X-ray diffraction (XRD), thermogravimetry (TG) and torque rheometry. The materials were characterized and potentially could be developed polymeric nano composites with technological applications using attapulgite fibers in the nanometer scale. (author)

  11. Effect of low-density polyethylene on smoke emissions from burning of simulated debris piles

    Science.gov (United States)

    Seyedehsan Hosseini; Qi Li; Manish Shrivastava; David R. Weise; David R. Cocker; J. Wayne Miller; Heejung S Jung

    2014-01-01

    Low-density polyethylene (LDPE) plastic is used to keep piled debris from silvicultural activities—activities associated with development and care of forests—dry to enable efficient disposal by burning. The effects of inclusion of LDPE in this manner on smoke emissions are not well known. In a combustion laboratory experiment, 2-kg mixtures of LDPE and manzanita (

  12. Gamma radiation effects on the rheological properties of high and low density polyethylenes

    International Nuclear Information System (INIS)

    Rangel-Nafaile, C.; Garcia-Rejon, A.; Garcia Leon, A.

    1986-01-01

    High energy radiation of polymeric materials is a topic of considerable interest from commercial and scientific points of view. Within an inert atmosphere, irradiation of polyethylene yields a crosslinking effect with a consequent improvement in its mechanical properties in comparison to the virgin materials. Additionally, if irradiated specimens are melted and recrystallized, the radiation-induced crosslinking hinders their crystalline growth altering dramatically their flow properties such as the elasticity. This work portrays the effects of the gamma radiation on the rheological properties of high and low density polyethylenes manufactured by PEMEX and analyzes the implications of theoretical results derived from the Acierno's model when it is implemented with the rheological properties of high energy irradiated polyethylenes. (author)

  13. Equipment evaluation for low density polyethylene encapsulated nitrate salt waste at the Rocky Flats Plant

    International Nuclear Information System (INIS)

    Yamada, W.I.; Faucette, A.M.; Jantzen, R.C.; Logsdon, B.W.; Oldham, J.H.; Saiki, D.M.; Yudnich, R.J.

    1993-01-01

    Mixed wastes at the Rocky Flats Plant (RFP) are subject to regulation by the Resource Conservation and Recovery Act (RCRA). Polymer solidification is being developed as a final treatment technology for several of these mixed wastes, including nitrate salts. Encapsulation nitrate salts with low density polyethylene (LDPE) has been the preliminary focus of the RFP polymer solidification effort. Literature reviews, industry surveys, and lab-scale and pilot-scale tests have been conducted to evaluate several options for encapsulating nitrate salts with LDPE. Most of the effort has focused on identifying compatible drying and extrusion technologies. Other processing options, specifically meltration and non-heated compounding machines, were also investigated. The best approach appears to be pretreatment of the nitrate salt waste brine in either a vertical or horizontal thin film evaporator followed by compounding of the dried waste with LDPE in an intermeshing, co-rotating, twin-screw extruder. Additional pilot-scale tests planned for the fall of 1993 should further support this recommendation. Preliminary evaluation work indicates that meltration is not possible at atmospheric pressure with the LDPE (Chevron PE-1409) provided by RFP. However, meltration should be possible at atmospheric pressure using another LDPE formulation with altered physical and rheological properties: Lower molecular weight and lower viscosity (Epoline C-15). Contract modifications are now in process to allow a follow-on pilot scale demonstration. Questions regarding changed safety and physical properties of the resultant LDPE waste form due to use of the Epoline C-15 will be addressed. No additional work with non-heated mixer compounder machines is planned at this time

  14. Biodegradation of Low-Density Polyethylene (LDPE) by Mixed Culture of Lysinibacillus xylanilyticus and Aspergillus niger in Soil

    Science.gov (United States)

    Esmaeili, Atefeh; Pourbabaee, Ahmad Ali; Alikhani, Hossein Ali; Shabani, Farzin; Esmaeili, Ensieh

    2013-01-01

    In this study, two strains of Aspergillus sp. and Lysinibacillus sp. with remarkable abilities to degrade low-density polyethylene (LDPE) were isolated from landfill soils in Tehran using enrichment culture and screening procedures. The biodegradation process was performed for 126 days in soil using UV- and non-UV-irradiated pure LDPE films without pro-oxidant additives in the presence and absence of mixed cultures of selected microorganisms. The process was monitored by measuring the microbial population, the biomass carbon, pH and respiration in the soil, and the mechanical properties of the films. The carbon dioxide measurements in the soil showed that the biodegradation in the un-inoculated treatments were slow and were about 7.6% and 8.6% of the mineralisation measured for the non-UV-irradiated and UV-irradiated LDPE, respectively, after 126 days. In contrast, in the presence of the selected microorganisms, biodegradation was much more efficient and the percentages of biodegradation were 29.5% and 15.8% for the UV-irradiated and non-UV-irradiated films, respectively. The percentage decrease in the carbonyl index was higher for the UV-irradiated LDPE when the biodegradation was performed in soil inoculated with the selected microorganisms. The percentage elongation of the films decreased during the biodegradation process. The Fourier transform infra-red (FT-IR), x-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine structural, morphological and surface changes on polyethylene. These analyses showed that the selected microorganisms could modify and colonise both types of polyethylene. This study also confirmed the ability of these isolates to utilise virgin polyethylene without pro-oxidant additives and oxidation pretreatment, as the carbon source. PMID:24086254

  15. Biodegradation of low-density polyethylene (LDPE by mixed culture of Lysinibacillus xylanilyticus and Aspergillus niger in soil.

    Directory of Open Access Journals (Sweden)

    Atefeh Esmaeili

    Full Text Available In this study, two strains of Aspergillus sp. and Lysinibacillus sp. with remarkable abilities to degrade low-density polyethylene (LDPE were isolated from landfill soils in Tehran using enrichment culture and screening procedures. The biodegradation process was performed for 126 days in soil using UV- and non-UV-irradiated pure LDPE films without pro-oxidant additives in the presence and absence of mixed cultures of selected microorganisms. The process was monitored by measuring the microbial population, the biomass carbon, pH and respiration in the soil, and the mechanical properties of the films. The carbon dioxide measurements in the soil showed that the biodegradation in the un-inoculated treatments were slow and were about 7.6% and 8.6% of the mineralisation measured for the non-UV-irradiated and UV-irradiated LDPE, respectively, after 126 days. In contrast, in the presence of the selected microorganisms, biodegradation was much more efficient and the percentages of biodegradation were 29.5% and 15.8% for the UV-irradiated and non-UV-irradiated films, respectively. The percentage decrease in the carbonyl index was higher for the UV-irradiated LDPE when the biodegradation was performed in soil inoculated with the selected microorganisms. The percentage elongation of the films decreased during the biodegradation process. The Fourier transform infra-red (FT-IR, x-ray diffraction (XRD and scanning electron microscopy (SEM were used to determine structural, morphological and surface changes on polyethylene. These analyses showed that the selected microorganisms could modify and colonise both types of polyethylene. This study also confirmed the ability of these isolates to utilise virgin polyethylene without pro-oxidant additives and oxidation pretreatment, as the carbon source.

  16. Zinc layered hydroxide salts: intercalation and incorporation into low-density polyethylene

    OpenAIRE

    Jaerger,Silvia; Zimmermann,Ademir; Zawadzki,Sonia Faria; Wypych,Fernando; Amico,Sandro Campos

    2014-01-01

    In this study, polymer composites using low-density polyethylene (LDPE) and layered hydroxide salts (LHS) were synthesized. The following compositions of LHS were obtained Zn5(OH)8(An-)2/n.yH2O, where A was varied in order to obtain hydrophilic (A = NO3 -) or hydrophobic (A = DDS- – dodecyl sulfate or DBS- – dodecyl benzene sulfonate). Synthesis was carried out by co-precipitation in alkaline medium and drying, being followed by characterization via Fourier-transform infrared spectroscopy, th...

  17. Assessment of the Resistance to External Factors of Low-Density Polyethylene Modified with Natural Fillers

    Directory of Open Access Journals (Sweden)

    Karolina Głogowska

    2017-12-01

    Full Text Available The study reports the results of investigation of basic processing and thermal properties of low-density polyethylene modified with two types of natural filler: wheat bran and pumpkin seed hulls, their content ranging from 5% to 15% relative to the matrix. In addition, the physical properties of the produced granulates are determined, i.e. the relationship between their density and the applied contents of the tested fillers. Furthermore, the study reports the results concerning the longitudinal shrinkage, abrasion resistance and cold water absorption of injection molded tensile specimens.

  18. Mechanical properties of low-density polyethylene filled by graphite nanoplatelets

    DEFF Research Database (Denmark)

    Carotenuto, G.; De Nicola, S.; Palomba, M.

    2012-01-01

    The mechanical properties of GNP/LDPE nanocomposites (graphite nanoplatelets/low density polyethylene) have been investigated, in order to establish the effect of nanoscale reinforcement within the polymer matrix. Results show that the presence of the filler does not involve a change...... in the microscopic structure of the polymer. However, on a macroscopic scale, GNPs limit the mobility of the polymer chains, resulting in an increase in stiffness for the final composite. Orientation of GNPs within the LDPE matrix is also an important issue that affects mechanical properties and it has been...

  19. Method for making a low density polyethylene waste form for safe disposal of low level radioactive material

    Science.gov (United States)

    Colombo, P.; Kalb, P.D.

    1984-06-05

    In the method of the invention low density polyethylene pellets are mixed in a predetermined ratio with radioactive particulate material, then the mixture is fed through a screw-type extruder that melts the low density polyethylene under a predetermined pressure and temperature to form a homogeneous matrix that is extruded and separated into solid monolithic waste forms. The solid waste forms are adapted to be safely handled, stored for a short time, and safely disposed of in approved depositories.

  20. Electron beam cross-linking of natural rubber/linear-low density polyethylene blends

    International Nuclear Information System (INIS)

    Ahmad, A.; Mohd, D. H.; Abdullah, I.

    2005-01-01

    Effects of electron beam irradiation on the mechanical properties and morphological structure of natural rubber/linear-low density polyethylene blend was investigated The natural rubber/linear-low density polyethylene blend was prepared by melt blending in a Haake internal mixer at 140 d ig C , rotor speed of 50 rpm, and in 15 min Liquid natural rubber was incorporated into the blend as a compatibilizer Samples in the form of 1 mm sheets were exposed to 50-300 kGy of electron beam irradiation and analyzed for swelling index and gel content, tensile strength, and surface morphology. The result Indicated that gel content and mechanical properties of the samples increased with radiation dosage. The honey-comb structure of the surface morphology in low dosage irradiated samples slowly transformed into a continuous matrix on increasing radiation dose The variation of mechanical and physical properties was due to Increase in cross-linking density in the rubber and plastic phases and rubber-plastic Interaction on irradiation

  1. DC Thermal Plasma Design and Utilization for the Low Density Polyethylene to Diesel Oil Pyrolysis Reaction

    Directory of Open Access Journals (Sweden)

    Hossam A. Gabbar

    2017-06-01

    Full Text Available The exponential increase of plastic production produces 100 million tonnes of waste plastics annually which could be converted into hydrocarbon fuels in a thermal cracking process called pyrolysis. In this research work, a direct current (DC thermal plasma circuit is designed and used for conversion of low density polyethylene (LDPE into diesel oil in a laboratory scale pyrolysis reactor. The experimental setup uses a 270 W DC thermal plasma at operating temperatures in the range of 625 °C to 860 °C for a low density polyethylene (LDPE pyrolysis reaction at pressure = −0.95, temperature = 550 °C with τ = 30 min at a constant heating rate of 7.8 °C/min. The experimental setup consists of a vacuum pump, closed system vessel, direct current (DC plasma circuit, and a k-type thermocouple placed a few millimeters from the reactant sample. The hydrocarbon products are condensed to diesel oil and analyzed using flame ionization detector (FID gas chromatography. The analysis shows 87.5% diesel oil, 1,4-dichlorobenzene (Surr, benzene, ethylbenzene and traces of toluene and xylene. The direct current (DC thermal plasma achieves 56.9 wt. % of diesel range oil (DRO, 37.8 wt. % gaseous products and minimal tar production. The direct current (DC thermal plasma shows reliability, better temperature control, and high thermal performance as well as the ability to work for long operation periods.

  2. Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, Manuel; Giraldo, Diego; Murillo, Edwin, E-mail: edwinalbertomurillo@gmail.com [Universidad de Antioquia, Medellin (Colombia); Universidad Francisco de Paula Santander, San Jose de Cucuta (Colombia)

    2017-01-15

    n this work, low density polyethylene (LDPE)/plasticised starch (TPS) blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young's modulus and tensile strength) improved ostensibly. The Young' modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior. (author)

  3. Effect of fiber geometry on macroscale friction of ordered low-density polyethylene nanofiber arrays.

    Science.gov (United States)

    Lee, Dae Ho; Kim, Yongkwan; Fearing, Ronald S; Maboudian, Roya

    2011-09-06

    Ordered low-density polyethylene (LDPE) nanofiber arrays are fabricated from silicon nanowire (SiNW) templates synthesized by a simple wet-chemical process based on metal-assisted electroless etching combined with colloidal lithography. The geometrical effect of nanofibrillar structures on their macroscale friction is investigated over a wide range of diameters and lengths under the same fiber density. The optimum geometry for contacting a smooth glass surface is presented with discussions on the compromise between fiber tip-contact area and fiber compliance. A friction design map is developed, which shows that the theoretical optimum design condition agrees well with the LDPE nanofiber geometries exhibiting high measured friction. © 2011 American Chemical Society

  4. Degradation assessment of natural weathering on low density polyethylene/thermoplastic soya spent powder blends

    Science.gov (United States)

    Nuradibah, M. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

    2015-07-01

    Soya spent powder was blended with low density polyethylene (LDPE) ranging from 5-25 wt%. Glycerol was added to soya spent powder (SSP) for preparation of thermoplastic soya spent powder (TSSP). Then, the blends were exposed to natural weathering for 6 months. The susceptibility of the LDPE/soya spent powder blends based on its tensile, morphological properties and structural changes was measured every three months. The tensile strength of LDPE/TSSP blends after 6 months of weathering was the lowest compared to the other blends whereas LDPE/SSP blends after 6 months of weathering demonstrated the lowest elongation at break (Eb). Large pore can be seen on the surface of 25 wt% of LDPE/SSP blends.

  5. Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

    Directory of Open Access Journals (Sweden)

    Manuel Guzmán

    Full Text Available Abstract In this work, low density polyethylene (LDPE/plasticized starch (TPS blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young’s modulus and tensile strength improved ostensibly. The Young’ modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior.

  6. Mechanical and morphological study of linear low density polyethylene (LLDPE)/cyperus odoratus (CY) biocomposites

    Science.gov (United States)

    Faris, N. A.; Noriman, N. Z.; Haron, Adli; Sam, S. T.; Hamzah, R.; Shayfull, Z.; Ghazali, M. F.

    2017-09-01

    The potential of Cyperus Odoratus (CY) as a filler was studied. The CY, in a powder form, was mixed with Linear Low Density Polyethylene (LLDPE), prior to being fed into a twin screw extruder and subsequently into an injection moulding machine to produce LLDPY/CY biocomposites. The Scanning Electron Microscope (SEM) was utilized and tensile tests were performed on the test specimens to characterize the structure and properties of the composites. The integration of CY powder and LLDPE resulted in an increment of the modulus of elasticity, but a reduction in tensile strength and elongation at break. The morphology characterization of these composites, determined through the SEM, showed poor interfacial adhesion between the filler and the thermoplastic LLDPE matrix.

  7. Characterization of injected linear low density polyethylene (LLDPE) irradiated by gamma-ray

    International Nuclear Information System (INIS)

    Oliveira, Ana C.F.; Parra, Duclerc F.; Ferreto, Helio F.R.; Lugao, Ademar B.

    2013-01-01

    The aim of this paper is to investigate of gamma irradiation effects on linear low density polyethylene (LLDPE) injected. Polymers processed by gamma radiation have new physical-chemical and mechanical properties. The ionizing radiation promotes chain scission and creates free radicals which can recombine, providing their annihilation, for crosslinking or branching. The polymer was irradiated with a source of 60 Co at doses of 5, 10, 20, 50 or 100 kGy at about 5 kGy s -1 rate, at room temperature. The changes in molecular structure of LLDPE were evaluated using melt flow index, gel fraction, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and thermogravimetry analysis (TG). The results showed that the properties depend on dose irradiation. (author)

  8. Thermal, tensile and rheological properties of low density polyethylene (LDPE) processed irradiated by gamma-ray

    International Nuclear Information System (INIS)

    Ferreto, Helio F.R.; Oliveira, Ana C.F. de; Parra, Duclerc F.; Lugao, Ademar B.

    2013-01-01

    The aim of this paper is to investigate structural changes of low density polyethylene (LDPE) modified by ionizing radiation (gamma rays). The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. The samples were prepare in hydraulic press in temperature 180 deg C after was irradiated with gamma source of 60 Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h in inert atmosphere. The changes in molecular structure of LDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere. (author)

  9. Tapanuli Organoclay Addition Into Linear Low Density Polyethylene-Pineapple Fiber Composites

    International Nuclear Information System (INIS)

    Adawiyah, Robiatul; Juwono, Ariadne L.; Roseno, Seto

    2010-01-01

    Linear low density polyethylene-Tapanuli organoclay-pineapple fiber composites were succesfully synthesized by a melt intercalation method. The clay was modified as an organoclay by a cation exchange reaction using hexadecyl trimethyl ammonium bromide (HDTMABr) surfactant. The X-ray diffraction results of the organoclay exhibited a higher basal spacing of 1.87 nm compared to the unmodified clay of 1.46 nm. The composite tensile strength was enhanced up to 46.4% with the 1 wt% organoclay addition. Both tensile and flexural moduli increased up to 150.6% and 43% with the 3 wt% organoclay addition to the composites. However, the flexural strength of the composites was not improved with the organoclay addition. The addition of organoclay has also decreased the heat deflection temperature of the composites.

  10. Mechanical properties of low-density polyethylene filled by graphite nanoplatelets

    International Nuclear Information System (INIS)

    Carotenuto, G; Palomba, M; De Nicola, S; Pullini, D; Horsewell, A; Hansen, T W; Nicolais, L

    2012-01-01

    The mechanical properties of GNP/LDPE nanocomposites (graphite nanoplatelets/low density polyethylene) have been investigated, in order to establish the effect of nanoscale reinforcement within the polymer matrix. Results show that the presence of the filler does not involve a change in the microscopic structure of the polymer. However, on a macroscopic scale, GNPs limit the mobility of the polymer chains, resulting in an increase in stiffness for the final composite. Orientation of GNPs within the LDPE matrix is also an important issue that affects mechanical properties and it has been evaluated by testing nanocomposites made by different manufacturing techniques (compression moulding and blown extrusion). The comparison between the experimental data and the Halpin–Tsai model shows that the orientation of GNPs due to the extrusion process leads to values of tensile modulus higher than that obtained with the randomly oriented disposition resulting from the compression moulding technique. (paper)

  11. Tapanuli Organoclay Addition Into Linear Low Density Polyethylene-Pineapple Fiber Composites

    Science.gov (United States)

    Adawiyah, Robiatul; Juwono, Ariadne L.; Roseno, Seto

    2010-12-01

    Linear low density polyethylene-Tapanuli organoclay-pineapple fiber composites were succesfully synthesized by a melt intercalation method. The clay was modified as an organoclay by a cation exchange reaction using hexadecyl trimethyl ammonium bromide (HDTMABr) surfactant. The X-ray diffraction results of the organoclay exhibited a higher basal spacing of 1.87 nm compared to the unmodified clay of 1.46 nm. The composite tensile strength was enhanced up to 46.4% with the 1 wt% organoclay addition. Both tensile and flexural moduli increased up to 150.6% and 43% with the 3 wt% organoclay addition to the composites. However, the flexural strength of the composites was not improved with the organoclay addition. The addition of organoclay has also decreased the heat deflection temperature of the composites.

  12. Hyperbranched polyester polyol plasticized tapioca starch/low density polyethylene blends

    International Nuclear Information System (INIS)

    Guzman, Manuel; Giraldo, Diego; Murillo, Edwin

    2017-01-01

    n this work, low density polyethylene (LDPE)/plasticised starch (TPS) blends were prepared. The TPS employed in this study was obtained by plasticization of tapioca starch with a hyperbranched polyester polyol. Differential scanning calorimetry analysis showed that the melting temperature increased with the TPS content. The opposite effect was exhibited in the crystallization temperature and additional changes were not observed during the heating. X-ray diffraction analysis showed a reduction in intensity of the peak at Bragg’s angle 17.5°, proving a diminution on A type crystallinity with the increasing amount of LDPE. Micrographs obtained by scanning electron microscopy exhibited starch granules without destructure. TPS acted as a filler to LDPE, since the mechanical properties (Young's modulus and tensile strength) improved ostensibly. The Young' modulus and tensile strength decreased with the amount of LDPE, however, the elongation at break exhibited an opposite behavior. (author)

  13. Characterisation of Cassava Bagasse and Composites Prepared by Blending with Low-Density Polyethylene

    Directory of Open Access Journals (Sweden)

    Fabiane Oliveira Farias

    2014-12-01

    Full Text Available The main objective of this study was to characterise the cassava bagasse and to evaluate its addition in composites. Two cassava bagasse samples were characterised using physicochemical, thermal and microscopic techniques, and by obtaining their spectra in the mid-infrared region and analysing them by using x-ray diffraction. Utilising sorption isotherms, it was possible to establish the acceptable conditions of temperature and relative humidity for the storage of the cassava bagasse. The incorporation of cassava bagasse in a low-density polyethylene (LDP matrix was positive, increasing the elasticity modulus values from 131.90 for LDP to 186.2 for 70% LDP with 30% SP bagasse. These results were encouraging because cassava bagasse could serve as a structural reinforcement, as well as having environmental advantages for its application in packaging, construction and automotive parts.

  14. Influence of flavour absorption by food-packaging materials (low-density polyethylene, polycarbonate and polyethylene terephthalate) on taste perception of a model solution and orange juice

    NARCIS (Netherlands)

    Willige, van R.W.G.; Linssen, J.P.H.; Legger, A.; Voragen, A.G.J.

    2003-01-01

    The influence of flavour absorption by low-density polyethylene (LDPE), polycarbonate (PC) and polyethylene terephthalate (PET) on taste perception of a model solution containing seven flavour compounds and orange juice in glass bottles was studied with and without pieces of the respective plastic

  15. Gamma irradiation effects on the grafting of low-density polyethylene with diethyl maleate

    International Nuclear Information System (INIS)

    Sanchez, Y.; Albano, C.; Karam, A.; Perera, R.; Silva, P.; Gonzalez, J.

    2005-01-01

    In this work, a low-density polyethylene (LDPE) was grafted with diethyl maleate (DEM) using gamma-rays from a Cobalt-60 source at different absorbed doses and monomer concentrations between 5 and 30 wt.%. This process was carried out in a decalin solution at 10 w/v% to obtain a homogeneous dispersion of the monomer into the polyethylene matrix. It was found that the grafting degree increases with the absorbed doses, as a consequence of the increased amount of energy given to the system, which made the grafting process more favorable. The grafting degree also increases with the concentration of DEM, because a higher concentration makes the insertion easier due to the increased availability of the free monomer. The highest grafting degree was obtained at 200 kGy of absorbed dose and with 30 wt.% of DEM. The melt flow index (MFI) values showed a decreasing trend as the absorbed dose was increased. This fact reveals that crosslinking and grafting are taking place simultaneously, this behavior being remarkable at higher irradiation doses. The results from thermogravimetric analysis (TGA) showed that the initial degradation temperatures remained almost unchanged with the absorbed dose

  16. The influence of oxidation on space charge formation in gamma-irradiated low-density polyethylene

    CERN Document Server

    Chen, G; Xie, H K; Banford, H M; Davies, A E

    2003-01-01

    The research presented in this paper investigates the role of oxidation in the formation of space charge in gamma-irradiated low-density polyethylene after being electrically stressed under dc voltage. Polyethylene plaques both with and without antioxidant were irradiated up to 500 kGy using a sup 6 sup 0 Co gamma source and space charge distributions were measured using the piezoelectric induced pressure wave propagation method. It has been found that a large amount of positive charge evolved adjacent to the cathode in the sample without antioxidant and was clearly associated with oxidation of the surface. The amount of charge formed for a given applied stress increased with the dose absorbed by the material. A model has been proposed to explain the formation of space charge and its profile. The charge decay after the removal of the external applied stress is dominated by a process being controlled by the cathode interfacial stress (charge injection) rather than a conventional RC circuit model. On the other ...

  17. Study of effects gamma radiation linear low density polyethylene (LLDPE) injected

    International Nuclear Information System (INIS)

    Oliveira, Ana Claudia Feitoza de

    2014-01-01

    The use of package sterilization through gamma radiation aim to reduce the microbiological contamination. The linear low density polyethylene (LLDPE) can be obtained by a process in solution, suspension or gaseous phase, depending on the type of the catalyzer used, that can be heterogeneous, or homogeneous, or metallocenes Ziegler-Natta. According to the literature, the gamma radiation presents a high penetration at polymeric materials causing the appearing of scissions, reticulation, and degradation when oxygen presence. This paper were irradiated with 60 Co with 2000 kCi of activity, in presence of air, samples of LLDPE injected. Utilized doses of 5, 10, 20, 50 or 100 kGy, and about 5 kGy.h -1 dose rates, at room temperature. After irradiation, the samples were heated for 60 min at 100 deg C to promote recombination and annihilation of residual radicals. For characterization of PEBLD were used methods; Melt flow index, swelling, gel fraction, Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (DRX), Thermogravimetric Analysis (TG), Dynamic Mechanical Analysis (DMA), rheological measurements, Scanning Electronic Microscopy and mechanical tests to identify the effects or gamma radiation in polyethylene. (author)

  18. Influence of non-thermal plasma forming gases on improvement of surface properties of low density polyethylene (LDPE)

    Energy Technology Data Exchange (ETDEWEB)

    Pandiyaraj, K. Navaneetha, E-mail: dr.knpr@gmail.com [Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, L and T by pass, Chinniyam Palayam (post), Coimbatore 641062 (India); Deshmukh, R.R. [Department of Physics, Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Ruzybayev, Inci; Shah, S. Ismat [Department of Physics and Astronomy, Department of Materials Science and Engineering, University of Delaware, 208 Dupont Hall, Newark, NJ (United States); Su, Pi-Guey [Department of Chemistry, Chinese Culture University, Taipei 111, Taiwan (China); Halleluyah, Jr. mercy; Halim, Ahmad Sukari [School of Medical Sciences, Health Campus Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2014-07-01

    Owing to the superior physico-chemical properties, the low density polyethylene (LDPE) has been widely used in the various industrial applications; especially in biomedical field for artificial organs, medical devices and disposable clinical apparatus. However, the poor anticoagulation property is one of the main drawbacks of the LDPE due to its poor surface properties. Therefore, in this paper we present the effect of plasma forming gases such as argon (Ar), oxygen (O{sub 2}), air and argon-oxygen (Ar + O{sub 2}) mixture on improvement of the surfaces properties of LDPE film using direct current (dc) excited glow discharge plasma. Contact angle with evaluation of surface energy, X-ray photo electron spectroscopy (XPS), atomic force microscopy (AFM) techniques were used to examine the change in surface properties such as hydrophilicity, chemical composition and surface topography, respectively. Furthermore, the hydrophobic recovery of the plasma treated LDPE was analyzed using ageing effect under different storage condition i.e. in air and water. The adhesive strength of the LDPE films was determined using T-peel test. In vitro tests were used to examine the blood compatibility of the surface modified LDPE films. It has been found that the hydrophilicity of the various plasma treated LDPE films was improved significantly due to the formation of oxygen containing polar groups such as OH, COO, C-O, C=O as confirmed by contact angle and XPS analysis. AFM revealed the changes in surface topography of plasma processed films. The gas mixture Ar + O{sub 2} plasma influenced the remarkable improvement on the surface properties of a LDPE film compared with other gaseous plasmas. These physiochemical changes induced by the plasma on the surface facilitate to improve the adhesive strength and blood compatibility.

  19. Influence of non-thermal plasma forming gases on improvement of surface properties of low density polyethylene (LDPE)

    International Nuclear Information System (INIS)

    Pandiyaraj, K. Navaneetha; Deshmukh, R.R.; Ruzybayev, Inci; Shah, S. Ismat; Su, Pi-Guey; Halleluyah, Jr. mercy; Halim, Ahmad Sukari

    2014-01-01

    Owing to the superior physico-chemical properties, the low density polyethylene (LDPE) has been widely used in the various industrial applications; especially in biomedical field for artificial organs, medical devices and disposable clinical apparatus. However, the poor anticoagulation property is one of the main drawbacks of the LDPE due to its poor surface properties. Therefore, in this paper we present the effect of plasma forming gases such as argon (Ar), oxygen (O 2 ), air and argon-oxygen (Ar + O 2 ) mixture on improvement of the surfaces properties of LDPE film using direct current (dc) excited glow discharge plasma. Contact angle with evaluation of surface energy, X-ray photo electron spectroscopy (XPS), atomic force microscopy (AFM) techniques were used to examine the change in surface properties such as hydrophilicity, chemical composition and surface topography, respectively. Furthermore, the hydrophobic recovery of the plasma treated LDPE was analyzed using ageing effect under different storage condition i.e. in air and water. The adhesive strength of the LDPE films was determined using T-peel test. In vitro tests were used to examine the blood compatibility of the surface modified LDPE films. It has been found that the hydrophilicity of the various plasma treated LDPE films was improved significantly due to the formation of oxygen containing polar groups such as OH, COO, C-O, C=O as confirmed by contact angle and XPS analysis. AFM revealed the changes in surface topography of plasma processed films. The gas mixture Ar + O 2 plasma influenced the remarkable improvement on the surface properties of a LDPE film compared with other gaseous plasmas. These physiochemical changes induced by the plasma on the surface facilitate to improve the adhesive strength and blood compatibility.

  20. Effect of low-density polyethylene on smoke emissions from burning of simulated debris piles.

    Science.gov (United States)

    Hosseini, Seyedehsan; Shrivastava, Manish; Qi, Li; Weise, David R; Cocker, David R; Miller, John W; Jung, Heejung S

    2014-06-01

    Low-density polyethylene (LDPE) plastic is used to keep piled debris from silvicultural activities--activities associated with development and care of forests--dry to enable efficient disposal by burning. The effects of inclusion of LDPE in this manner on smoke emissions are not well known. In a combustion laboratory experiment, 2-kg mixtures of LDPE and manzanita (Arctostaphylos sp.) wood containing 0, 0.25, and 2.5% LDPE by mass were burned. Gaseous and particulate emissions were sampled in real time during the entire flaming, mixed combustion phase--when the flaming and smoldering phases are present at the same time--and during a portion of the smoldering phase. Analysis of variance was used to test significance of modified combustion efficiency (MCE)--the ratio of concentrations of fire-integrated excess CO2 to CO2 plus CO--and LDPE content on measured individual compounds. MCE ranged between 0.983 and 0.993, indicating that combustion was primarily flaming; MCE was seldom significant as a covariate. Of the 195 compounds identified in the smoke emissions, only the emission factor (EF) of 3M-octane showed an increase with increasing LDPE content. Inclusion of LDPE had an effect on EFs of pyrene and fluoranthene, but no statistical evidence of a linear trend was found. Particulate emission factors showed a marginally significant linear relationship with MCE (0.05 burned. In general, combustion of wet piles results in lower MCEs and consequently higher levels of emissions. Current air quality regulations permit the use of burning to dispose of silvicultural piles; however, inclusion of low-density polyethyelene (LDPE) plastic in silvicultural piles can result in a designation of the pile as waste. Waste burning is not permitted in many areas, and there is also concern that inclusion of LDPE leads to toxic air emissions.

  1. Safety and durability of low-density polyethylene bags in solar water disinfection applications.

    Science.gov (United States)

    Danwittayakul, Supamas; Songngam, Supachai; Fhulua, Tipawan; Muangkasem, Panida; Sukkasi, Sittha

    2017-08-01

    Solar water disinfection (SODIS) is a simple point-of-use process that uses sunlight to disinfect water for drinking. Polyethylene terephthalate (PET) bottles are typically used as water containers for SODIS, but a new SODIS container design has recently been developed with low-density polyethylene (LDPE) bags and can overcome the drawbacks of PET bottles. Two nesting layers of LDPE bags are used in the new design: the inner layer containing the water to be disinfected and the outer one creating air insulation to minimize heat loss from the water to the surroundings. This work investigated the degradation of LDPE bags used in the new design in actual SODIS conditions over a period of 12 weeks. The degradation of the LDPE bags was investigated weekly using a scanning electron microscope, Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometer, and tensile strength tester. It was found that the LDPE bags gradually degraded under the sunlight due to photo-oxidation reactions, especially in the outer bags, which were directly exposed to the sun and surroundings, leading to the reduction of light transmittance (by 11% at 300 nm) and tensile strength (by 33%). In addition, possible leaching of organic compounds into the water contained in the inner bags was examined using gas chromatography-mass spectrometer. 2,4-Di-tert-butylphenol was found in some SODIS water samples as well as the as-received water samples, in the concentration range of 1-4 μg/L, which passes the Environmental Protection Agency Drinking Water Guidance on Disinfection By-Products.

  2. Effect of organoclay on morphology and properties of linear low density polyethylene and Vietnamese cassava starch biobased blend.

    Science.gov (United States)

    Nguyen, D M; Vu, T T; Grillet, Anne-Cécile; Ha Thuc, H; Ha Thuc, C N

    2016-01-20

    Linear low density polyethylene (LLDPE)/thermal plastic starch (TPS) blend was studied to prepare the biobased nanocomposite material using organoclay nanofil15 (N15) modified by alkilammonium as the reinforced phase. The LLDPE/TPS blend and its nanocomposites were elaborated by melt mixing method at 160 °C for 7 min. And the compounded sample was filmed by blowing method at three different zones of temperature profile which are 160-170-165 °C. The good dispersion of clay in the polymer blend matrix is showed by X-ray diffraction (XRD) and transmission electronic microscopy (TEM), and a semi-exfoliated structure was obtained. The thermal and mechanical properties of materials are enhanced when N15 is added to the mixture. The effect of N15 on morphology and particles size of TPS phase is also investigated. The biodegradation test shows that more than 60% in weight of LLDPE/TPS film is degraded into CO2, H2O, methane and biomass after 5 months in compost soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Potential of Using Recycled Low-Density Polyethylene in Wood Composites Board

    Directory of Open Access Journals (Sweden)

    A. C. Igboanugo

    2011-03-01

    Full Text Available The aim of this study was to investigate the suitability of using recycled low density polyethylene (RLDPE in wood board manufacturing. The composite board was produced by compressive moulding by increasing the percentage LDPE from 30 to 50wt% with interval of 10wt% at a temperatures of 140 and 180oC, pressure of 30-40 Kg/cm2 and pressing time 7-13minutes. The microstructure and mechanical properties: modulus of rupture (MOR, modulus of elasticity (MOE, Tensile strength, impact strength properties of boards were determined. The results showed that high modulus of rupture of 20.31N/mm2and MOE of 1363N/mm2 were obtained from board produced at 140oC, 60/40wt% wood particles/LDPE content. The uniform distribution of the particles and the recycled LDPE in the microstructure of the composites board is the major factor responsible for the improvement in the mechanical properties. The results showed that the MOE, MOR meets the minimum requirements of the European standards, for general purpose. The boards produced had tensile strength that is within the requirement. Hence this LDPE can be used in board production for general purpose applications.

  4. Properties of concrete modified with waste Low Density Polyethylene and saw dust ash

    Science.gov (United States)

    Srimanikandan, P.; Sreenath, S.

    2017-07-01

    The increase in industrialization creates need for disposal of large quantity of by-products. To overcome the difficulty of disposal, these by-products can be used as a replacement for raw material. In this concern, non-conventional industrial wastes such as plastic bags, PET bottles, pulverized waste Low Density Polyethylene (LDPE) and biological waste such as saw-dust ash, coconut coir were used as a replacement in concrete. In this project, saw-dust ash and pulverized waste LDPE were introduced as the partial replacement for cement and fine aggregates respectively. 0%, 5%, 10%, 15% and 20% of sand by volume was replaced with LDPE and 0%, 1%, 3%, 5% and 10% of cement by volume was replaced with saw dust ash. Standard cube, cylinder and prism specimens were cast to assess the compressive strength, split tensile strength and flexural strength of modified concrete after 28 days of curing. Optimum percentage of replacement was found by comparing the test results. The mix with 5% of LDPE and 3% of saw dust ash showed a better result among the other mixes.

  5. Zinc layered hydroxide salts: intercalation and incorporation into low-density polyethylene

    Directory of Open Access Journals (Sweden)

    Silvia Jaerger

    2014-12-01

    Full Text Available In this study, polymer composites using low-density polyethylene (LDPE and layered hydroxide salts (LHS were synthesized. The following compositions of LHS were obtained Zn5(OH8(An-2/n.yH2O, where A was varied in order to obtain hydrophilic (A = NO3- or hydrophobic (A = DDS- - dodecyl sulfate or DBS- - dodecyl benzene sulfonate. Synthesis was carried out by co-precipitation in alkaline medium and drying, being followed by characterization via Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy. A variable amount of filler was then incorporated into the LDPE via extrusion, which was then injection molded to obtain specimens for evaluating tensile properties (Young's modulus, tensile strength, strain at break and toughness. For comparison, the sodium salts of the surfactants (NaDDS and NaDBS were also used as fillers in LDPE. The X-ray diffraction results indicated that the hydrophobic LHS were exfoliated in the polymer matrix, whereas the hydrophilic LHS was only delaminated. In the LDPE composites, melting and crystallization temperatures were nearly constant, along with the crystallinity indexes. The mechanical properties were mainly varied when the organophilic LHS was used. Overall, fillers based on LHS, especially those containing hydrophobic anions, may be interesting alternatives in the production of reinforced thermoplastics.

  6. Pyrolysis of olive residue/low density polyethylene mixture:Part I Thermogravimetric kinetics

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper demonstrates the thermal pyrolysis of olive residue, low density polyethylene (LDPE) and olive residue/LDPE mixture in an inert atmosphere of N2 using thermogravimetric analysis (TGA). Measurements were carried out in the temperature range 300K~973K at heating rates of 2K/min, 10K/min, 20K/min and 50K/min. Based on the results obtained, three temperature regimes were selected for studying the non-isothermal kinetics of olive residue/LDPE mixture. The first two were dominated by the olive residue pyrolysis, while the third was linked to the LDPE pyrolysis, which occurred at much higher temperatures. Discrepancies between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on co-pyrolysis. The maximum degradation temperatures of each component in the mixture were higher than those the individual components;thus an increase in thermal stability was expected. The kinetic parameters associated with thermal degradation were determined using Friedman isoconversional method.

  7. Evaluation of corn husk fibers reinforced recycled low density polyethylene composites

    International Nuclear Information System (INIS)

    Youssef, Ahmed M.; El-Gendy, Ahmed; Kamel, Samir

    2015-01-01

    Responding to the community demand for disposal of environmental problematic agricultural and polymer waste, composite sheets using recycled low-density polyethylene (R-LDPE) and corn husk fibers were prepared by melt compounding and compression molding. These composites were prepared in different concentrations (5, 10, 15, and 20%) of powder corn husk with 125 μ particle size based on R-LDPE matrix. Beside the importance of property improvement, an additional incentive was responding to the social demand for the disposal of environmental problematic agricultural waste. The influence of loading rate on R-LDPE crystallization behavior, mechanical, and swilling properties were investigated. Increasing in fiber loading led to increased moduli and tensile strength while hardness was decreased. X-ray diffraction (XRD) examinations indicated that introducing fiber to R-LDPE matrix did not change characteristic peak position. The thermal stability of the prepared composites was evaluated using differential scanning calorimetry (DSC) which displayed that the R-LDPE had significantly larger peak heat flow during cooling run than the blank R-LDPE, indicating higher crystallization rates for R-LDPE. The prepared composites materials can be used in packaging applications. - Highlights: • New composite based on recycled LDPE and corn husk fibers has been prepared. • The prepared composite has a benefit of minimizing solid waste problem. • The prepared composites were characterized using XRD, FTIR and DSC. • Crystallization behaviors, mechanical and swilling properties of the prepared composites were investigated

  8. Evaluation of corn husk fibers reinforced recycled low density polyethylene composites

    Energy Technology Data Exchange (ETDEWEB)

    Youssef, Ahmed M., E-mail: amyoussef27@yahoo.com [Packing and Packaging Materials Department, National Research Center, Dokki, P.C. 12622, Cairo (Egypt); El-Gendy, Ahmed; Kamel, Samir [Cellulose and Paper Department, National Research Center, Dokki, Cairo (Egypt)

    2015-02-15

    Responding to the community demand for disposal of environmental problematic agricultural and polymer waste, composite sheets using recycled low-density polyethylene (R-LDPE) and corn husk fibers were prepared by melt compounding and compression molding. These composites were prepared in different concentrations (5, 10, 15, and 20%) of powder corn husk with 125 μ particle size based on R-LDPE matrix. Beside the importance of property improvement, an additional incentive was responding to the social demand for the disposal of environmental problematic agricultural waste. The influence of loading rate on R-LDPE crystallization behavior, mechanical, and swilling properties were investigated. Increasing in fiber loading led to increased moduli and tensile strength while hardness was decreased. X-ray diffraction (XRD) examinations indicated that introducing fiber to R-LDPE matrix did not change characteristic peak position. The thermal stability of the prepared composites was evaluated using differential scanning calorimetry (DSC) which displayed that the R-LDPE had significantly larger peak heat flow during cooling run than the blank R-LDPE, indicating higher crystallization rates for R-LDPE. The prepared composites materials can be used in packaging applications. - Highlights: • New composite based on recycled LDPE and corn husk fibers has been prepared. • The prepared composite has a benefit of minimizing solid waste problem. • The prepared composites were characterized using XRD, FTIR and DSC. • Crystallization behaviors, mechanical and swilling properties of the prepared composites were investigated.

  9. Reorganizing Neural Network System for Two Spirals and Linear Low-Density Polyethylene Copolymer Problems

    Directory of Open Access Journals (Sweden)

    G. M. Behery

    2009-01-01

    Full Text Available This paper presents an automatic system of neural networks (NNs that has the ability to simulate and predict many of applied problems. The system architectures are automatically reorganized and the experimental process starts again, if the required performance is not reached. This processing is continued until the performance obtained. This system is first applied and tested on the two spiral problem; it shows that excellent generalization performance obtained by classifying all points of the two-spirals correctly. After that, it is applied and tested on the shear stress and the pressure drop problem across the short orifice die as a function of shear rate at different mean pressures for linear low-density polyethylene copolymer (LLDPE at 190∘C. The system shows a better agreement with an experimental data of the two cases: shear stress and pressure drop. The proposed system has been also designed to simulate other distributions not presented in the training set (predicted and matched them effectively.

  10. Preparation and Characterisation of Linear Low-Density Polyethylene / Thermoplastic Starch Blends Filled with Banana Fibre

    Science.gov (United States)

    Kahar, A. W. M.; Ann, L. Ju

    2017-06-01

    In this study, the influence of banana fibre (BF) loading using sodium hydroxide (NaOH) pre-treated and succinic anhydride-treated (SA) BF on the mechanical properties of linear low-density polyethylene (LLDPE)/thermoplastic starch (TPS) matrix is investigated. LLDPE/TPS/BF composites were developed under different BF conditions, with and without chemical modifications with the BF content ranging from 5% to 30% based on the total composite. The tensile strength showed an increase with an increase of fibre content up to 10%, thereby decreasing gradually beyond this level. NaOH pre-treated and SA treated BF added with LLDPE/TPS composite displays a higher tensile strength as compared to untreated BF in LLDPE/TPS composites. Thermal behaviour of the BF incorporated in LLDPE/TPS composite was characterised using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). This showed that SA treated BF exhibits better thermal stability, compared to other composites. This is because of the improvement in interfacial adhesion existing between both the fibre and matrix. In addition, a morphology study confirmed that pre-treated and treated BF had excellent interfacial adhesion with LLDPE/TPS matrix, leading to better mechanical properties of resultant composites.

  11. Self-sensing performance of MWCNT-low density polyethylene nanocomposites

    Science.gov (United States)

    Gupta, Tejendra K.; Kumar, S.; Khan, Amal Z.; Varadarajan, Kartik M.; Cantwell, Wesley J.

    2018-01-01

    Carbon nanotubes (CNTs) based polymer nanocomposites offer a range of remarkable properties. Here, we demonstrate self-sensing performance of low density polyethylene (LDPE)-multiwalled carbon nanotubes (MWCNTs) nanocomposites for the first time. The dispersion of the CNTs and the morphology of the nanocomposites was investigated using scanning electron microscopy, x-ray diffraction and Raman spectroscopic techniques. The thermal properties were measured using thermal gravimetric analysis and differential scanning calorimetry and were found to increase with increasing wt% of MWCNTs in LDPE matrix. An overall improvement in ultimate tensile strength, yield strength and Young’s modulus was found to be 59.6%, 48.5% and 129.3%, respectively for 5.0 wt% loading of MWCNTs. The electrical percolation threshold was observed at 1.0 wt% of MWCNTs and the highest electrical conductivity of 2.8 × 10-2 Scm-1 was observed at 5.0 wt% loading of MWCNTs. These piezo-resistive nanocomposites offer tunable self-sensing capabilities with gauge factors in the ranges of 17-52 and 42-530 in linear elastic (strain ˜3%) and inelastic regimes (strain ˜15%) respectively. Our demonstration would provide guidelines for the fabrication of low cost, self-sensing MWCNT-LDPE nanocomposites for potential use as civil water pipelines and landfill membranes.

  12. Influence of food matrix on absorption of flavour compounds by linear low-density polyethylene: proteins and carbohydrates

    NARCIS (Netherlands)

    Willige, van R.W.G.; Linssen, J.P.H.; Voragen, A.G.J.

    2000-01-01

    The influence of oil and food components in real food products on the absorption of four flavour compounds (limonene, decanal, linalool and ethyl 2-methyl butyrate) into linear low-density polyethylene (LLDPE) was studied using a large volume injection GC in vial extraction method. Model food

  13. THE EFFECT OF DIAMETER ON THE MECHANICAL-PROPERTIES OF AMORPHOUS-CARBON FIBERS FROM LINEAR LOW-DENSITY POLYETHYLENE

    NARCIS (Netherlands)

    PENNING, JP; LAGCHER, R; PENNINGS, AJ

    The mechanical properties of amorphous carbon fibers, derived from linear low density polyethylene strongly depend on the fibre diameter, which may be attributed to the presence of a skin/core structure in these fibres. High strength carbon fibres could thus be prepared by using thin precursor

  14. Experimental investigation of the effect of titanium dioxide and barium titanate additives on DC transient currents in low density polyethylene

    DEFF Research Database (Denmark)

    Khalil, M.S; Henk, Peter O; Henriksen, Mogens

    1988-01-01

    The effect of titanium dioxide as a semiconductive additive and barium titanate as a highly polar additive on the DC transient currents in low-density polyethylene is investigated. Experiments were made using thick specimens under a high electric field (>25×106 V/m) and a constant temperature of 40...

  15. THE ANALYSIS OF PARTIAL DISCHARGE (PD FROM ELECTRICAL TREEING IN LINEAR LOW DENSITY POLYETHYLENE (LLDPE AND HIGH DENSITY POLYETHYLENE (HDPE

    Directory of Open Access Journals (Sweden)

    Hermawan Hermawan

    2012-02-01

    Full Text Available Recently, the transmission of electric energy has been developed by insulated cable. The suitable materialas an insulated cable is LLDPE and HDPE. In order to understand the quality of insulation system, themeasuring of PD has done. PD could begin completely insulation failure (breakdown. Therefore, it is veryimportant to understand the characteristic of PD and the enclose event on it, because PD is a main factorwhich caused insulation failure.This paper presents the result of PD measurement in the laboratory that used needle-plane electrode. Itwas supported by equipments such as osiloskop Digital GDS 2104 GW Instek, HPF, and RC detector.Polymer sample that used in this research is LLDPE (Linier Low Density Polyethylene and HDPE with 20x 4 x 25 mm3 dimension in each. Needle was made by steel (length 50 mm and diameter 1.15 mm, it wasstick to the polymer material. The distance between needle to the plane is 5 mm. The applied voltage foreach sample was 16 kVrms, 18 kVrms, 20 kVrms and 22 kVrms. The Taking of PD data was done in thefirst minute, 10th minute, 20th and so on until 180th minute.The measurement result shows that the characteristic of PD number and maximum charge as a function oftime and as a function of applied voltage inclined increasing both on LLDPE and HDPE. But, PD intensityin HDPE is higher than LLDPE.

  16. Mechanical and thermal properties of biocomposites from nonwoven industrial Fique fiber mats with Epoxy Resin and Linear Low Density Polyethylene

    Directory of Open Access Journals (Sweden)

    Miguel A. Hidalgo-Salazar

    2018-03-01

    Full Text Available In this work Linear Low Density Polyethylene-nonwoven industrial Fique fiber mat (LLDPE-Fique and Epoxy Resin-nonwoven industrial Fique fiber mat (EP-Fique biocomposites were prepared using thermocompression and resin film infusion processes. Neat polymeric matrices and its biocomposites were tested following ASTM standards in order to evaluate tensile and flexural mechanical properties. Also, thermal behavior of these materials has been studied by differential scanning calorimetry (DSC and thermogravimetric analysis (TGA. Tensile and flexural test revealed that nonwoven Fique reinforced composites exhibited higher modulus and strength but lower deformation capability as compared with LLDPE and EP neat matrices. TG thermograms showed that nonwoven Fique fibers incorporation has an effect on the thermal stability of the composites. On the other hand, Fique fibers did not change the crystallization and melting processes of the LLDPE matrix but restricts the motion of EP macromolecules chains thus increases the Tg of the EP-Fique composite. Finally, this work opens the possibility of considering non-woven Fique fibers as a reinforcement material with a high potential for the manufacture of biocomposites for automotive applications. In addition to the processing test specimens, it was also possible to manufacture a part of LLDPE-Fique, and one part of EP-Fique. Keywords: Biocomposites, Natural materials, Nonwoven Fique fiber mat, LLDPE, Epoxy Resin

  17. Mechanical and thermal properties of biocomposites from nonwoven industrial Fique fiber mats with Epoxy Resin and Linear Low Density Polyethylene

    Science.gov (United States)

    Hidalgo-Salazar, Miguel A.; Correa, Juan P.

    2018-03-01

    In this work Linear Low Density Polyethylene-nonwoven industrial Fique fiber mat (LLDPE-Fique) and Epoxy Resin-nonwoven industrial Fique fiber mat (EP-Fique) biocomposites were prepared using thermocompression and resin film infusion processes. Neat polymeric matrices and its biocomposites were tested following ASTM standards in order to evaluate tensile and flexural mechanical properties. Also, thermal behavior of these materials has been studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Tensile and flexural test revealed that nonwoven Fique reinforced composites exhibited higher modulus and strength but lower deformation capability as compared with LLDPE and EP neat matrices. TG thermograms showed that nonwoven Fique fibers incorporation has an effect on the thermal stability of the composites. On the other hand, Fique fibers did not change the crystallization and melting processes of the LLDPE matrix but restricts the motion of EP macromolecules chains thus increases the Tg of the EP-Fique composite. Finally, this work opens the possibility of considering non-woven Fique fibers as a reinforcement material with a high potential for the manufacture of biocomposites for automotive applications. In addition to the processing test specimens, it was also possible to manufacture a part of LLDPE-Fique, and one part of EP-Fique.

  18. Effect of ionizing radiation on mechanical and thermal properties of low-density polyethylene containing pro-degradant agents

    International Nuclear Information System (INIS)

    Bardi, Marcelo A.G.; Kodama, Yasko; Machado, Luci D.B.; Giovedi, Claudia; Rosa, Derval S.

    2009-01-01

    The wide use of plastics on packages of short-lifetime products has presented harmful consequences for the environment due to their low degradation rate. By this way, improved results to the bio-assimilation of polyolefins have been achieved by the incorporation of pro-oxidant components. The aim of this work is to evaluate the mechanical and thermal behavior of low-density polyethylene (LDPE) modified by those agents and submitted to ionizing radiation by gamma rays. LDPE was modified using a masterbatch containing calcium stearate (CaSt), or magnesium stearate (MgSt) or Clariant R commercial metallic complex. The final amount of stearate in modified LDPE was 0.2%. The films were obtained by compression molding. Samples were gamma irradiated at absorbed doses of 15 kGy and 100 kGy. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were performed on samples, as well as mechanical analysis by universal testing machine. Thermal properties of samples presenting pro-degradant agents were affected by the ionizing radiation in the dose range studied, and some of the mechanical properties were clearly modified by reducing their values of tensile strength at break and elongation at break. (author)

  19. Effect of ionizing radiation on mechanical and thermal properties of low-density polyethylene containing pro-degradant agents

    Energy Technology Data Exchange (ETDEWEB)

    Bardi, Marcelo A.G.; Kodama, Yasko; Machado, Luci D.B., E-mail: magbardi@ipen.b, E-mail: ykodama@ipen.b, E-mail: lmachado@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Giovedi, Claudia, E-mail: giovedi@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil); Rosa, Derval S., E-mail: derval.rosa@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)

    2009-07-01

    The wide use of plastics on packages of short-lifetime products has presented harmful consequences for the environment due to their low degradation rate. By this way, improved results to the bio-assimilation of polyolefins have been achieved by the incorporation of pro-oxidant components. The aim of this work is to evaluate the mechanical and thermal behavior of low-density polyethylene (LDPE) modified by those agents and submitted to ionizing radiation by gamma rays. LDPE was modified using a masterbatch containing calcium stearate (CaSt), or magnesium stearate (MgSt) or Clariant{sup R} commercial metallic complex. The final amount of stearate in modified LDPE was 0.2%. The films were obtained by compression molding. Samples were gamma irradiated at absorbed doses of 15 kGy and 100 kGy. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were performed on samples, as well as mechanical analysis by universal testing machine. Thermal properties of samples presenting pro-degradant agents were affected by the ionizing radiation in the dose range studied, and some of the mechanical properties were clearly modified by reducing their values of tensile strength at break and elongation at break. (author)

  20. Effect of Ar ion on the surface properties of low density polyethylene

    Science.gov (United States)

    Zaki, M. F.

    2016-04-01

    In this paper, low-density polyethylene (LDPE) was irradiated by argon ion with different fluences up to 1015ions/cm2. The optical, chemical and hardness properties have been investigated using UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and micro-indentation tester, respectively. The results showed the ion beam bombardment induced decreases in the transmittance of the irradiated polymer samples. This change in transmittance can be attributed to the formation of conjugated bonds i.e. possible formation of defects and/or carbon clusters. The indirect optical band gap decreased from 3.0 eV for the pristine sample to 2.3 eV for that sample irradiated with the highest fluence of the Ar ion beam. Furthermore, the number of carbon atoms and clusters increased with increasing Ar ion fluences. FTIR spectra showed the formation of new bands of the bombarded polymer samples. Furthermore, polar groups were created on the surface of the irradiated samples which refer to the increase of the hydrophilic nature of the surface of the irradiated samples. The Vicker's hardness increased from 4.9 MPa for the pristine sample to 17.9 MPa for those bombarded at the highest fluence. This increase is attributed to the increase in the crosslinking and alterations of the bombarded surface into hydrogenated amorphous carbon, which improves the hardness of the irradiated samples. The bombarded LDPE surfaces may be used in special applications to the field of the micro-electronic devices and shock absorbers.

  1. Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soojong; Moon, Heejang; Kim, Jinkon, E-mail: jkkim@kau.ac.kr

    2015-08-10

    Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

  2. Effect of gamma irradiation on linear low density polyethylene/magnesium hydroxide/sepiolite composite

    International Nuclear Information System (INIS)

    Shafiq, Muhammad; Yasin, Tariq

    2012-01-01

    Radiation crosslinking is generally used to improve the thermo-mechanical properties of the composites. A study has been carried out to investigate the effect of gamma radiation on the thermo-mechanical properties of linear low density polyethylene containing magnesium hydroxide (MH) and sepiolite (SP) as non-halogenated flame retardant additives. The developed composites are irradiated at different doses upto maximum of 150 kGy. Infrared spectra of the irradiated composites reveal the reduction in the intensity of O-H band with increase in the absorbed doses, thus indicates a distinct structural change in MH at higher doses. The thermogravimetric analysis results of unirradiated and composites irradiated at low doses (≤75 kGy) show two steps weight loss, which is changed to single step at higher doses with lower thermal stability. The melting temperature (T m ) and crystallization temperature (T c ) of irradiated composites are lowered with irradiation whereas Vicat softening temperature (VST) is increased. The increasing trend in gel content with increase in the absorbed dose confirms the presence of crosslinked network. The mechanical properties, results show significant improvement in the modulus of irradiated composites. The results also confirm that MH gradually loses its OH functionality with irradiation. - Highlights: → We have studied the effect of γ radiation on LLDPE containing Mg(OH) 2 and sepiolite. → IR spectra of the irradiated composites show reduction in the intensity of O-H band. → Reduction in OH band show a distinct structural change in Mg(OH) 2 at higher doses. → TGA results show two steps weight loss at low doses and one step at higher doses. → These results confirm that MH gradually loses its OH functionality with irradiation.

  3. Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

    International Nuclear Information System (INIS)

    Kim, Soojong; Moon, Heejang; Kim, Jinkon

    2015-01-01

    Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

  4. Influence of fast neutrons on thermophysical properties of pure and borated low density polyethylene

    International Nuclear Information System (INIS)

    El-Khatib, A. M.; Kassem, M.

    1990-01-01

    The impact of radiation crosslinking on the mechanical, thermomechanical and electrical conductivity properties of LDPE and borated polyethylene have been studied and evaluated. The 8% borated polyethylene samples have added a new advantage where the tensile strength has increased to the maximum and then it became constant at higher crosslink density. Moreover, the electrical conductivity of 8% borated polyethylene is much higher than pure and 4% borated polyethylene. (author). 16 refs., 8 figs

  5. Flammability of radiation cross-linked low density polyethylene as an insulating material for wire and cable

    International Nuclear Information System (INIS)

    Basfar, A.A.

    2002-01-01

    Various formulations of low-density polyethylene blended with ethylene vinyl acetate were prepared to improve the flame retardancy for wire and cable applications. The prepared formulations were cross-linked by γ-rays to 50, 100, 150 and 200 kGy in the presence of trimethylolpropane triacrylate (TMPTA). The effect of thermal aging on mechanical properties of these formulations were investigated. In addition, the influence of various combinations of aluminum trihydroxide and zinc borate as flame retardant fillers on the flammability was explored. Limiting oxygen index (LOI) and average extent of burning were used to characterize the flammability of investigated formulations. An improved flame retardancy of low density polyethylene was achieved by various combinations of flame ratardant fillers and cross-linking by gamma radiation

  6. Preparation and tensile properties of linear low density polyethylene/rambutan peels (Nephelium chryseum Blum.) flour blends

    Science.gov (United States)

    Nadhirah, A. Ainatun.; Sam, S. T.; Noriman, N. Z.; Voon, C. H.; Samera, S. S.

    2015-05-01

    The effect of rambutan peels flour (RPF) content on the tensile properties of linear low density polyethylene filled with rambutan peel flour was studied. RPF was melt blended with linear low-density polyethylene (LLDPE). LLDPE/RPF blends were prepared by using internal mixer (brabender) at 160 °C with the flour content ranged from 0 to 15 wt%. The tensile properties were tested by using a universal testing machine (UTM) according to ASTM D638. The highest tensile strength was observed for pure LLDPE while the tensile strength LLDPE/RPF decreased gradually with the addition of rambutan peels flour content from 0% to 15%. Young's modulus of 63 µm to 250 µm rambutan peels blends with LLDPE with the fiber loading of 0 - 15 wt% increased with increasing fiber loading.

  7. Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

    International Nuclear Information System (INIS)

    Grosso, M.F. del; Chappa, V.C.; Arbeitman, C.R.; Garcia Bermudez, G.; Behar, M.

    2009-01-01

    In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

  8. Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Grosso, M.F. del, E-mail: delgrosso@tandar.cnea.gov.a [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Chappa, V.C. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Arbeitman, C.R. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Garcia Bermudez, G. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Escuela de Ciencia y Tecnologia, UNSAM (Argentina); Behar, M. [Instituto de Fisica, UFRGS, Porto Alegre (Brazil)

    2009-10-01

    In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

  9. Influence of different factors on the destruction of films based on polylactic acid and oxidized polyethylene

    Science.gov (United States)

    Podzorova, M. V.; Tertyshnaya, Yu. V.; Pantyukhov, P. V.; Shibryaeva, L. S.; Popov, A. A.; Nikolaeva, S.

    2016-11-01

    Influence of different environmental factors on the degradation of film samples based on polylactic acid and low density polyethylene with the addition of oxidized polyethylene was studied in this work. Different methods were used to find the relationship between degradation and ultraviolet, moisture, oxygen. It was found that the addition of oxidized polyethylene, used as a model of recycled polyethylene, promotes the degradation of blends.

  10. Influence of adipic acid on tensile and morphology properties of linear low density polyethylene/rambutan peels flour blends

    Science.gov (United States)

    Nadhirah, A. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

    2015-07-01

    This study investigate about the tensile and morphological properties of degradable polymer produced from linear low density polyethylene/rambutan peel flour (LLDPE/RPF) blends and adipic acid (AA) was used as a compatibilizer by varying the rambutan peel flour (RPF) amount from 0-25wt%. The samples were subjected to tensile and morphological tests. AA compatibilized showed higher strength compared to uncompatibilized blends. The Young's modulus for LLDPE/RPF blends increased with increasing flour content. However, the addition of adipic acid had reduced the Young's Modulus.

  11. Utilização de filmes de polietileno de baixa densidade(PEBD para prolongar a vida pós-colheita de morangos, cv. oso grande The use of low density polyethylene packing to prolong the postharvest life of 'oso grande' strawberries

    Directory of Open Access Journals (Sweden)

    Joel Donazzolo

    2003-02-01

    para as variáveis avaliadas, embora o uso do filme de PEBD tenha proporcionado qualidade superior.The experiment was carried out with the aim to evaluate the effect of modified atmosphere, using low-density polyethylene packaging (FPBD, on the quality of 'Oso Grande' strawberries (Fragaria ananassa L. stored at 0ºC and 20ºC. Approximately 300g of fruits were placed into trays covered with a 15µm PVC film, and 6 trays were involved with a FPBD film with 22 [T2] or 45µm [T3] thickness and then placed into a commercial wood box. Control fruits [T1] were not involved with FPBD film. After removing air, 15kPa CO2 was injected into the FPBD bags before closing. The experimental design was a completely randomized blocs, with 3 replicates, each composed by 6 trays with 17 fruits. The evaluations were done after exposing the fruits for 7 days at 20ºC, and 14 days at 0ºC plus 3 days at 20ºC. Fruits stored at 20ºC with FPBD films had lower rot incidence, less red color, lower titratable acidity and higher pulp firmness. However, high CO2 partial pressure accumulated in the 45µm coatings (30kPa, which caused alcoholic taste. The fruits stored at 0ºC did not show any differences between the evaluated treatments, but fruits involved with FPBD generally showed better quality.

  12. RF magnetron sputtering and evaporation of polyisobutylene and low density polyethylene

    Czech Academy of Sciences Publication Activity Database

    Kousal, J.; Hanuš, J.; Choukourov, A.; Hlídek, P.; Biederman, H.; Slavinská, D.; Zemek, Josef

    2005-01-01

    Roč. 200, 1-4 (2005), s. 472-475 ISSN 0257-8972 R&D Projects: GA MŠk(CZ) OC 527.10; GA MŠk(CZ) ME 553 Institutional research plan: CEZ:AV0Z10100521 Keywords : magnetron * radio frequency * sputtering * polyethylene * polyisobutylene Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.646, year: 2005

  13. Biodegradation of low density polyethylene by the action of a microbial consortium isolated from a landfill, Lima, Peru

    Directory of Open Access Journals (Sweden)

    Diego Uribe

    2011-05-01

    Full Text Available In this paper, we describe the isolation and biodegradation activity of microorganisms on low density polyethylene. The microorganisms were collected from plastic materials with evidence of deterioration from a landfill. The samples were filtered and selected in a mineral salts medium at pH 5.5 and 7 for bacteria and fungi respectively. Six strains were isolated, identified as Pseudomonas sp. Hyalodendron sp., Penicillium sp. and Rhodotorula sp. Microbial activity was evidenced by changes in the infrared spectrum of polyethylene with respect to the polymer without treatment. Reduction of carbonyl index (83.89% at pH 7 and 4.08% at pH 5.5 and double bonds index (19.77% at pH 7 and 6.47% at pH 5.5 were observed. Finally we determined the percentage of weight lost by the polyethylene subjected to activity of the strains, with a decrease of 5.4% at pH 7 and 4.8% at pH5, 5.

  14. Effect of the addition of lithium carbonate on the properties of low density polyethylene

    International Nuclear Information System (INIS)

    Hoshimura, Yoshikazu; Yamamoto, Shigeru

    1992-01-01

    For improvement of the properties of polyethylene (PE), γ-ray was irradiated to the lithium carbonate added PE. An increase in the numbers of OH and C=C bonds was observed from FT-IR measurements. The melting temperature (or the vanishing temperature of crystallinity by X-ray diffraction) of the lithium carbonate added PE after γ-ray irradiation (10 6 Gy) was 20degC higher than that of the PE's with no additives and with quartz added PE. The lamellae of lithium carbonate added PE were not observed in the scanning electron micrographs. This vanishing of lamellae of the lithium carbonate added PE was also suggested by the extinction of the maltese cross with a polarizing microscope. (author)

  15. Comparative studies on physico-mechanical properties of composite materials of low density polyethylene and raw/calcined kaolin

    Directory of Open Access Journals (Sweden)

    Amit Mallik

    2015-06-01

    Full Text Available The paper describes the preparation of the composite materials of low density polyethylene (LDPE as the base mixed separately with raw kaolin and the same calcined at 800 °C under the same variation in weight percentage using single-screw extruder and a mixing machine operated at a temperature between 190 and 200 °C. Some of the mechanical and physical properties such as Young's modulus, elongation at break, shore hardness and water absorption were determined at different weight fractions of filler (0, 2, 7, 10 and 15%. It was found that the addition of filler increases the mechanical properties. Absorption test was done in water at different immersion times for different composites. The degree of water absorption of composite materials was found to decrease with increasing wt% of kaolin filler (0–15% according to Fick's law. Calcined kaolin produces better mechanical properties than raw kaolin.

  16. Viscoelastic behaviour and fracture toughness of linear-low-density polyethylene reinforced with synthetic boehmite alumina nanoparticles

    Directory of Open Access Journals (Sweden)

    D. Pedrazzoli

    2013-08-01

    Full Text Available Aim of the present study is to investigate how synthetic boehmite alumina (BA nanoparticles modify the viscoleastic and fracture behaviour of linear low-density polyethylene. Nanocomposites containing up to 8 wt% of untreated and octyl silane-functionalized BA nanoparticles, were prepared by melt compounding and hot pressing. The BA nanoparticles were finely and unformly dispersed within the matrix according to scanning electron microscopy inspection. The results of quasi-static tensile tests indicated that nanoparticles can provide a remarkable stiffening effect at a rather low filler content. Short term creep tests showed that creep stability was significatively improved by nanofiller incorporation. Concurrently, both storage and loss moduli were enhanced in all nanocomposites, showing better result for surface treated nanoparticles. The plane-stress fracture toughness, evaluated by the essential work of fracture approach, manifested a dramatic increase (up to 64% with the BA content, with no significant differences among the various types of BA nanoparticles.

  17. Advantageous use of SSA technique to observe effects of thickness, antioxidant and oxygen in gamma irradiated low density polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Perez, C.J., E-mail: cjperez@fi.mdp.edu.ar [Research Institute of Material Science and Technology (INTEMA), National Research Council (CONICET), Engineering Faculty, Mar del Plata University, Av. J.B. Justo 4302, 7600 Mar del Plata (Argentina); Failla, M.D. [Planta Piloto de Ingenieria Quimica-PLAPIQUI (UNS-CONICET), Camino ' La Carrindanga' Km 7, 8000 Bahia Blanca (Argentina); Carella, J.M. [Research Institute of Material Science and Technology (INTEMA), National Research Council (CONICET), Engineering Faculty, Mar del Plata University, Av. J.B. Justo 4302, 7600 Mar del Plata (Argentina)

    2012-06-20

    Highlights: Black-Right-Pointing-Pointer Information from successive self-nucleation and annealing technique is analyzed. Black-Right-Pointing-Pointer Oxygen and antioxidants reduce crosslinking efficiency by reaction with free radicals. Black-Right-Pointing-Pointer Recognizable differences are obtained in samples irradiated at different atmospheres. - Abstract: Information obtained from successive self-nucleation and annealing (SSA) technique is analyzed, paying special attention to the observable effects of samples thickness and antioxidant and oxygen concentrations. Molecular structure changes for low density polyethylene (LDPE) samples, irradiated under three different atmospheres for doses between 33 and 222 kGy were analyzed, with emphasis on the changes of longer polymethylene crystallizable lengths. Antioxidant and oxygen concentrations were varied for samples of different thickness to study the effects on degradation. The changes in the molecular structure were followed simultaneously by SSA and Infrared spectroscopy (FTIR) via carbonyl group concentration. Preliminary quantifications of the SSA technique sensitivity are also advanced.

  18. Dielectric properties of nanosilica/low-density polyethylene composites: The surface chemistry of nanoparticles and deep traps induced by nanoparticles

    Directory of Open Access Journals (Sweden)

    S. Ju

    2014-09-01

    Full Text Available Four kinds of nanosilica particles with different surface modification were employed to fabricate low-density polyethylene (LDPE composites using melt mixing and hot molding methods. The surface chemistry of modified nanosilica was analyzed by X-ray photoelectron spectroscopy. All silica nanoparticles were found to suppress the space charge injection and accumulation, increase the volume resistivity, decrease the permittivity and dielectric loss factor at low frequencies, and decrease the dielectric breakdown strength of the LDPE polymers. The modified nanoparticles, in general, showed better dielectric properties than the unmodified ones. It was found that the carrier mobility, calculated from J–V curves using the Mott-Gurney equation, was much lower for the nanocomposites than for the neat LDPE.

  19. Low-density silicon thin films for lithium-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Demirkan, M.T., E-mail: tmdemirkan@ualr.edu [Department of Physics and Astronomy, University of Arkansas at Little Rock, Little Rock, AR 72204 (United States); Department of Materials Science and Engineering, Gebze Technical University, Kocaeli (Turkey); Trahey, L. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Karabacak, T. [Department of Physics and Astronomy, University of Arkansas at Little Rock, Little Rock, AR 72204 (United States)

    2016-02-01

    Density of sputter deposited silicon (Si) thin films was changed by a simple working gas pressure control process, and its effects on the cycling performance of Si films in Li-ion batteries as anodes was investigated. Higher gas pressure results in reduced film densities due to a shadowing effect originating from lower mean free path of sputter atoms, which leads to a wider angular distribution of the incoming flux and formation of a porous film microstructure. Si thin film anodes of different densities ranging from 2.27 g/cm{sup 3} (film porosity ~ 3%) down to 1.64 g/cm{sup 3} (~ 30% porosity) were fabricated by magnetron sputtering at argon pressures varying from 0.2 Pa to 2.6 Pa, respectively. High density Si thin film anodes of 2.27 g/cm{sup 3} suffered from an unstable cycling behavior during charging/discharging depicted by a continuous reduction in specific down to ~ 830 mAh/g at the 100th cycle. Electrochemical properties of lower density films with 1.99 g/cm{sup 3} (~ 15% porosity) and 1.77 g/cm{sup 3} (~ 24% porosity) got worse resulting in only ~ 100 mAh/g capacity at 100th cycle. On the other hand, as the density of anode was further reduced down to about 1.64 g/cm{sup 3} (~ 30% porosity), cycling stability and capacity retention significantly improved resulting in specific capacity values ~ 650 mAh/g at 100th cycle with coulombic efficiencies of > 98%. Enhancement in our low density Si film anodes are believed to mainly originate from the availability of voids for volumetric expansion during lithiation and resulting compliant behavior that provides superior mechanical and electrochemical stability. - Highlights: • Low density Si thin films were studied as Li-ion battery anodes. • Low density Si films were fabricated by magnetron sputter deposition. • Density of Si films reduced down to as low as ~ 1.64 g/cm{sup 3} with a porosity of ~ 30% • Low density Si films presented superior mechanical properties during cycling.

  20. Adhesion, Growth, and Maturation of Vascular Smooth Muscle Cells on Low-Density Polyethylene Grafted with Bioactive Substances

    Directory of Open Access Journals (Sweden)

    Martin Parizek

    2013-01-01

    Full Text Available The attractiveness of synthetic polymers for cell colonization can be affected by physical, chemical, and biological modification of the polymer surface. In this study, low-density polyethylene (LDPE was treated by an Ar+ plasma discharge and then grafted with biologically active substances, namely, glycine (Gly, polyethylene glycol (PEG, bovine serum albumin (BSA, colloidal carbon particles (C, or BSA+C. All modifications increased the oxygen content, the wettability, and the surface free energy of the materials compared to the pristine LDPE, but these changes were most pronounced in LDPE with Gly or PEG, where all the three values were higher than in the only plasma-treated samples. When seeded with vascular smooth muscle cells (VSMCs, the Gly- or PEG-grafted samples increased mainly the spreading and concentration of focal adhesion proteins talin and vinculin in these cells. LDPE grafted with BSA or BSA+C showed a similar oxygen content and similar wettability, as the samples only treated with plasma, but the nano- and submicron-scale irregularities on their surface were more pronounced and of a different shape. These samples promoted predominantly the growth, the formation of a confluent layer, and phenotypic maturation of VSMC, demonstrated by higher concentrations of contractile proteins alpha-actin and SM1 and SM2 myosins. Thus, the behavior of VSMC on LDPE can be regulated by the type of bioactive substances that are grafted.

  1. The Potential of Lignolytic Trichoderma Isolates in LDPE (Low Density Polyethylene) Plastic Biodegradation

    Science.gov (United States)

    Hikmah, M.; Setyaningsih, R.; Pangastuti, A.

    2018-03-01

    Plastic is experiencing buildup in the environment. Biodegradation process can be used as an alternative for LDPE plastic degradation because the process is environmentally friendly. Some fungi of the genus Trichoderma are known to have a role in plastic biodegradation. This study aims to find out how the potential of that lignolytic Trichoderma spp. isolates in LDPE biodegradation. Five isolates were screened by growing on MSMB (mineral salt medium broth) emulsified LDPE powder, with 35 days incubation at 30°C and shaking at 80 rpm. TL1, TL4, and TL5 are the three most potential isolates, indicated by the growth marked by increasing colony size on screening media. They were then tested for biodegradability by growing the isolates in MSMA (mineral salt medium agar) which then inoculated by 4 sheets of sterile LDPE 1x3 cm2 above the colony surface, incubated for 5, 15, 25 and 35 days. The degredability assessment is done by measuring the weight loss of LDPE sheets after biodegradation treatment. The obtained degradability percentage of TL1, TL4, and TL5 are 4.87%, 7.12%, and 7,51% respectively. The visual micrograph of LDPE film by SEM showed the appearance of damage and unevenness on the surface of the post-degradation film.

  2. Development of tailored indigenous marine consortia for the degradation of naturally weathered polyethylene films

    OpenAIRE

    Syranidou, Evdokia; Karkanorachaki, Katerina; Amorotti, Filippo; Repouskou, Eftychia; Kroll, Kevin; Kolvenbach, Boris; Corvini, Philippe F-X; Fava, Fabio; Kalogerakis, Nicolas

    2017-01-01

    This study investigated the potential of bacterial-mediated polyethylene (PE) degradation in a two-phase microcosm experiment. During phase I, naturally weathered PE films were incubated for 6 months with the indigenous marine community alone as well as bioaugmented with strains able to grow in minimal medium with linear low-density polyethylene (LLDPE) as the sole carbon source. At the end of phase I the developed biofilm was harvested and re-inoculated with naturally weathered PE films. Bac...

  3. Reversed preparation of low-density poly(divinylbenzene/styrene) foam columns coated with gold films

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Yinhai; Wang, Ni; Li, Yaling; Yao, Mengqi; Gan, Haibo; Hu, Wencheng, E-mail: huwc@uestc.edu.cn

    2016-06-15

    Highlights: • A reversed fabrication of low density foam columns coated with gold films was proposed. • The uniformity in thickness and purity of gold film are easy to be controlled. • A compact layer is prepared through an electrophoretic deposition method. • A low density (12 mg/cc) foam column coated with gold film is obtained. - Abstract: This work aims to fabricate low-density, porous, non-conductive, structural poly(divinylbenzene/styrene) foam columns by high-internal-phase emulsion templating. We prepare these non-conductive foam columns coated with a thin gold layer by electrochemical deposition and the reversed preparation technique. As expected, the density of the foam obtained through this novel method was about 12 mg cm{sup −3}, and the thickness of the gold coating was about 3 μm. We performed field emission scanning electron microscopy to morphologically and microstructurally characterize the products and X-ray diffraction and energy dispersive spectroscopy to determine the composition of the gold coating.

  4. Thermoplastic elastomers blends based on linear low density polyethylene, ethylene-1-octene copolymers and ground rubber tire

    Directory of Open Access Journals (Sweden)

    Marisa Cristina Guimarães Rocha

    2014-01-01

    Full Text Available Blends of linear low density polyethylene (LLDPE ethylene-1-octene copolymers (EOC, with different 1-octene (OC content, and ground rubber tire (GRT were prepared by melt mixing in a twin screw extruder. Five different compositions of LLDPE/EOC/GRT blends were processed in the extruder to evaluate the effect of EOC addition to the LLDPE/GRT blends. The addition of EOC to LLDPE/GRT blends improves the mechanical properties. Besides, the replacement of 5% of GRT by EOC grades (OC = 20 or 30 wt % in the 50/50 LLDPE/GRT blend, leads to a significant increase of ultimate tensile properties. The EOC comonomer content affects the properties of LLDPE/EOC and LLDPE/EOC/GRT blends. Dynamical-mechanical analyses showed that, with the addition of EOC to LLDPE/GRT blends, the Tg of GRT and the Tg of EOC are closer. This effect is more pronounced when the EOC with the highest content of comonomer (30 wt % is added to LLDPE/GRT blend. In this case, only one peak related to the Tg of the rubber phase can be visualized in the amorphous region. These findings indicate that EOC may act as compatibilizer agent for LLDPE/GRT blends.

  5. A comparative study on thermal, mechanical and dielectric characteristics of low density polyethylene crosslinked by radiation and chemical methods

    International Nuclear Information System (INIS)

    Kim, B.H.; Ling, D.Y.; Kim, J.S.

    1976-01-01

    A comparative study on thermal, static mechanical and dielectric characteristics were made over a temperature range of ca. 20 0 C to 320 0 C and a frequency range of KHZ band on low density polyethylene specimens crosslinked, respectively, by radiation and chemical method. The thermal property of both specimens shows that softening point appears to unchange by crosslinking however, melting and liquidizing temperatures attain rapid increase at the imitation of crosslinking. Mechanical properties show little difference to both specimens crosslinked by different method, further the behaviors were discussed in connection with the relaxation of molecular segments in amorphous phase. Dose dependent dielectric characteristics observed at ambient temperature under several fixed frequencies exhibit extremities at ca. 20 Mrad and the behaviors also were interpreted qualitatively by taking into consideration of dipole concentration change in amorphous phase together with the role of specimen geometry to the depth of oxidative layer. Observing frequency dependent dielectric characteristics, it was also proved that ionic conduction loss is appreciably greater in the specimen prepared by chemical method than that by radiation. (author)

  6. Effect of carrageenan on properties of biodegradable thermoplastic cassava starch/low-density polyethylene composites reinforced by cotton fibers

    International Nuclear Information System (INIS)

    Prachayawarakorn, Jutarat; Pomdage, Wanida

    2014-01-01

    Highlights: • We prepared the TPCS/LDPE composites modified by carrageenan and/or cotton fibers. • The IR O–H stretching peak of the modified composites shifts to lower wavenumber. • Stress and Young’s modulus of the modified composites increase significantly. • The modified composites degrade faster than the non-modified composite. - Abstract: Applications of biodegradable thermoplastic starch (TPS) have been restricted due to its poor mechanical properties, limited processability and high water uptake. In order to improve properties and processability, thermoplastic cassava starch (TPCS) was compounded with low-density polyethylene (LDPE). The TPCS/LDPE blend was, then, modified by a natural gelling agent, i.e. carrageenan and natural fibers, i.e. cotton fibers. All composites were compounded and processed using an internal mixer and an injection molding machine, respectively. It was found that stress at maximum load and Young’s modulus of the TPCS/LDPE composites significantly increased by the addition of the carrageenan and/or the cotton fibers. The highest mechanical properties were obtained from the TPCS/LDPE composites modified by both the carrageenan and the cotton fibers. Percentage water absorption of all of the TPCS/LDPE composites was found to be similar. All modified composites were also degraded easier than the non-modified one. Furthermore, all the composites were analyzed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Scanning electron microscopy (SEM)

  7. Steady State Simulation of Two-Gas Phase Fluidized Bed Reactors in Series for Producing Linear Low Density Polyethylene

    Directory of Open Access Journals (Sweden)

    Ali Farhangiyan Kashani

    2012-12-01

    Full Text Available A linear low density polyethylene (LLDPE production process, including two- fuidized bed reactors in series (FBRS and other process equipment, was completely simulated by Aspen Polymer Plus software. Fluidized bed reactors were considered as continuous stirred tank reactors (CSTR consisted of polymer and gas phases. POLY-SRK and NRTL-RK equations of state were used to describe polymer and non-polymer streams, respectively. In this simulation, a kinetic model, based on a double active site heterogeneous Ziegler-Natta catalyst was used for simulation of LLDPE process consisting of two FBRS. Simulator using this model has the capability to  predict a number of  principal characteristics of LLDPE such as melt fow index (MFI, density, polydispersity index, numerical and weight average molecular weights (Mn,Mw and copolymer molar fraction (SFRAC. The results of the simulation were compared with industrial plant data and a good agreement was observed between the predicted model and plant data. The simulation results show the relative error of about 0.59% for prediction of polymer mass fow and 2.67% and 0.04% for prediction of product MFI and density, respectively.

  8. Evaluation of the effect of reprocessing on the structure and properties of low density polyethylene/thermoplastic starch blends.

    Science.gov (United States)

    Peres, Anderson M; Pires, Ruthe R; Oréfice, Rodrigo L

    2016-01-20

    The great quantity of synthetic plastic discarded inappropriately in the environment is forcing the search for materials that can be reprocessable and biodegradable. Blends between synthetic polymers and natural and biodegradable polymers can be good candidates of such novel materials because they can combine processability with biodegradation and the use of renewable raw materials. However, traditional polymers usually present high levels of recyclability and use the well-established recycling infrastructure that can eventually be affected by the introduction of systems containing natural polymers. Thus, this work aims to evaluate the effect of reprocessing (simulated here by multiple extrusions) on the structure and properties of a low density polyethylene/thermoplastic starch (LDPE/TPS) blend compared to LDPE. The results indicated that multiple extrusion steps led to a reduction in the average size of the starch-rich phases of LDPE/TPS blends and minor changes in the mechanical and rheological properties of the materials. Such results suggest that the LDPE/TPS blend presents similar reprocessability to the LDPE for the experimental conditions used. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Evaluation of the physico-chemical properties of nanocomposites of low density linear polyethylene and organophilic montmorillonite obtained by fusion

    International Nuclear Information System (INIS)

    Arndt, Aline; Sandrin, Bianca M.; Pezzin, A.P.T.; Meier, Marcia M.; Balzer, Palova S.; Tavares, Maria I.B.

    2016-01-01

    In this project they were produced and characterized nanocomposite organoclay applied to linear low density polyethylene in order to improve their physicochemical properties. Samples were produced by means of extrusion and injection process, varying proportions of nanoclay (2; 2.5; 3.0 and 3.5%) in LLDPE. Samples nanocomposites were characterized by TGA, DSC and Flammability test (UL-94). The TGA analysis showed that adding nanoclay increased thermal stability, especially for LLDPE / OMMT2,0 sample increased thermal stability at 4.4%. By DSC it was found that samples with nanoclay incorporation did not affect the Tm of LLDPE, though the increase of nanoclay raised the degree of crystallinity of the samples 52.7% in LLDPE / 2.5 OMMT sample. The flammability results show that the sample LLDPE / OMMT 2.0 showed a decrease of 37.77% in the flame propagation velocity. The NMR showed that the samples up LLDPE / 2.5 OM has an exfoliated nanocomposite formation. (author)

  10. Investigation of utilization of process of polyethylene waste of low density for creation of competitive materials with application of phenol formaldehyde oligomers

    International Nuclear Information System (INIS)

    Agakishieva, M.A.; Bilalov, Ya. M; Ibragimova, S. M; Dadasheva, G. I; Rezaei, Rudabeh

    2007-01-01

    Full text: The possibility of the utilization of low density polyethylene wastes by means of their modification with phenol formaldehyde oligomers (Ph FO) and PhFO with the thiourathenes has been investigation. Theology properties of the investigated systems showed that the obtained compositions can be able to be processed by the ordinary methods such as extrusion and casting

  11. Transmissividade a radiação solar do polietileno de baixa densidade utilizado em estufas Solar radiation transmissivity through low density polyethylene used in greenhouses

    Directory of Open Access Journals (Sweden)

    Galileo Adeli Buriol

    1995-01-01

    Full Text Available Determinou-se a transmissividade à radiação solar do polietileno de baixa densidade utilizado em estufas. O experimento foi conduzido em uma estufa tipo Capela com dimensões de 10m x 25m, coberta com polietileno transparente de baixa densidade, com espessura de 100µm e aditivado com anti-UV, instalada no Departamento de Fitotecnia da Universidade Federal de Santa Maria, RS - Brasil. A radiação solar global diária incidente no interior e exterior da estufa foi medida no período de julho de 1991 a janeiro de 1992 e também a fração difusa da radiação solar em dias com diferentes condições atmosféricas e de condensação no filme plástico durante o período de maio a julho de 1993. A transmissividade média da radiação solar global foi de 56,2% nas primeiras horas do dia e de 81,3% nas horas próximas ao meio-dia. A fração difusa da radiação solar global foi mais elevada no interior da estufa do que no exterior, evidenciando o efeito dispersante do plástico e da condensação do vapor d'água na superfície interna do filme.The transmissivity of the solar radiation by polyethylene cover used in plastic greenhouses was evaluated in the Central Region of the Rio Grande do Sul State, Brazil. The study was carried out inside a 10m x 25m greenhouse covered with low density transparent polyethylene with 100µm thickness, located at Federal University of Santa Maria. Incoming global solar radiation inside and outside was measured daily dunng July, 1991 to January, 1992. The effect of polyethylene cover on diffuse solar radiation was determined dunng 1993 year. The average transmissivity of global solar radiation was 56.2% early in the moming and 81.3% at near noonday. Diffuse solar radiation proportion was higher inside than outside the greenhouse and enhanced when water condenses on the inner surface of the film.

  12. The effect of natural weathering on irradiated polyethylene films

    International Nuclear Information System (INIS)

    Khoylou, F.; Hassan Pour, S.

    2002-01-01

    Polyethylene is one of the extensive used plastics in outdoor uses. Outdoor durability of PE in modem agriculture is very important because of large scale food production. UV radiations contained in solar spectrum are the main cause of degradation in outdoor uses of plastics. So, light stabilization of PE has made considerable progress since the early years of its outdoor use. Radiation crosslinking of PE films for improving UV stability is one of the new research fields. In this work,the effect of UV stabilizers on the chemical and mechanical stability of PE have been compared with UV stabilizers and radiation crosslinking together. For this reason two low density polyethylene films were prepared.One film contained 3% of photostabilizers and antioxidant,and the other film was free of additives. The films were irradiated by EB at doses of 30-300 kGy, these crosslinked PE films were exposed to the outdoor condition for 2 years. Determination of the gel content shows that significant crosslinking yields are obtained at high doses. Effect of crosslinking and outdoor exposure on the degradation of stabilized and unstabilized PE films have been studied by FTIR. Data of FTIR show that outdoor degradation of unstabilized PE promote rapidly after irradiation and cause to distortion of samples after 4 months. While, stabilized PE samples show low changes during 2 years outdoor exposure. Mechanical properties of stabilized and unstabilized crosslinked PE films are also presented in this paper. (Author)

  13. Langmuir-Blodgett films of polyaniline for low density lipoprotein detection

    Energy Technology Data Exchange (ETDEWEB)

    Matharu, Zimple [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India); Sumana, G. [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Gupta, Vinay [Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India); Malhotra, B.D., E-mail: bansi.malhotra@gmail.co [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi-110012 (India)

    2010-11-30

    Langmuir-Blodgett (LB) films of polyaniline (PANI) were utilized for the fabrication of impedimetric immunosensor for detection of human plasma low density lipoprotein (LDL) by immobilizing anti-apolipoprotein B (AAB) via EDC-NHS coupling. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy. AAB/PANI-SA LB immunoelectrodes studied by EIS spectroscopy revealed detection of LDL in the wide range of 0.018 {mu}M (6 mg/dl) to 0.39 {mu}M (130 mg/dl), covering the physiological range in blood, with a sensitivity of 11.25 k{Omega} {mu}M{sup -1}.

  14. Langmuir-Blodgett films of polyaniline for low density lipoprotein detection

    International Nuclear Information System (INIS)

    Matharu, Zimple; Sumana, G.; Gupta, Vinay; Malhotra, B.D.

    2010-01-01

    Langmuir-Blodgett (LB) films of polyaniline (PANI) were utilized for the fabrication of impedimetric immunosensor for detection of human plasma low density lipoprotein (LDL) by immobilizing anti-apolipoprotein B (AAB) via EDC-NHS coupling. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy. AAB/PANI-SA LB immunoelectrodes studied by EIS spectroscopy revealed detection of LDL in the wide range of 0.018 μM (6 mg/dl) to 0.39 μM (130 mg/dl), covering the physiological range in blood, with a sensitivity of 11.25 kΩ μM -1 .

  15. Environmental risk assessment of low density polyethylene unit using the method of failure mode and effect analysis

    Directory of Open Access Journals (Sweden)

    Salati Parinaz

    2012-01-01

    Full Text Available The ninth olefin plan of Arya Sasol Petrochemical Company (A.S.P.C. is regarded the largest gas Olefin Unit located on Pars Special Economic Energy Zone (P.S.E.E.Z. Considering the importance of the petrochemical unit, its environmental assessment seems necessary to identify and reduce potential hazards. For this purpose, after determining the scope of the study area, identification and measurement of the environmental parameters, environmental risk assessment of the unit was carried out using Environment Failure Mode and Effect Analysis (EFMEA. Using the noted method, sources causing environmental risks were identified, rated and prioritized. Beside, the impacts of the environmental aspects derived from the unit activities as well as their consequences were also analyzed. Furthermore, the identified impacts were prioritized based on Risk Priority Number (RPN and severity level of the consequences imposed on the affected environment. After performing statistical calculations, it was found that the environmental aspects owing the risk priority number higher than 15 have a high level of risk. Results obtained from Low Density Polyethylene Unit revealed that the highest risk belongs to the emergency vent system with risk priority number equal to 48. It is occurred due to imperfect performance of the reactor safety system leading to the emissions of ethylene gas, particles, and radioactive steam as well as air and noise pollutions. Results derived from secondary assessment of the environmental aspects, through difference in calculated RPN and activities risk levels showed that employing modern methods and risk assessment are have remarkably reduced the severity of risk and consequently detracted the damages and losses incurred on the environment.

  16. Determination of silicone rubber and low-density polyethylene diffusion and polymer/water partition coefficients for emerging contaminants.

    Science.gov (United States)

    Pintado-Herrera, Marina G; Lara-Martín, Pablo A; González-Mazo, Eduardo; Allan, Ian J

    2016-09-01

    There is a growing interest in assessing the concentration and distribution of new nonregulated organic compounds (emerging contaminants) in the environment. The measurement of freely dissolved concentrations using conventional approaches is challenging because of the low concentrations that may be encountered and their temporally variable emissions. Absorption-based passive sampling enables the estimation of freely dissolved concentrations of hydrophobic contaminants of emerging concern in water. In the present study, calibration was undertaken for 2 polymers, low-density polyethylene (LDPE) and silicone rubber for 11 fragrances, 5 endocrine-disrupting compounds, 7 ultraviolet (UV) filters, and 8 organophosphate flame retardant compounds. Batch experiments were performed to estimate contaminant diffusion coefficients in the polymers (Dp ), which in general decreased with increasing molecular weight. The values for fragrances, endocrine-disrupting compounds, and UV filters were in ranges similar to those previously reported for polycyclic aromatic hydrocarbons, but were 1 order of magnitude lower for organophosphate flame retardant compounds. Silicone rubber had higher Dp values than LDPE and was therefore selected for further experiments to calculate polymer/water partition coefficients (KPW ). The authors observed a positive correlation between log KPW and log octanol/water partition coefficient values. Field testing of silicone rubber passive samplers was undertaken though exposure in the River Alna (Norway) for an exposure time of 21 d to estimate freely dissolved concentration. Some fragrances and UV filters were predominant over other emerging and regulated contaminants, at levels up to 1600 ng L(-1) for galaxolide and 448 ng L(-1) for octocrylene. Environ Toxicol Chem 2016;35:2162-2172. © 2016 SETAC. © 2016 SETAC.

  17. Facile Fabrication of Electrically Conductive Low-Density Polyethylene/Carbon Fiber Tubes for Novel Smart Materials via Multiaxial Orientation.

    Science.gov (United States)

    Li, Yijun; Nie, Min; Wang, Qi

    2018-01-10

    Electromechanical sensors are indispensable components in functional devices and robotics application. However, the fabrication of the sensors still maintains a challenging issue that high percolation threshold and easy failure of conductive network are derived from uniaxial orientation of conductive fillers in practical melt processing. Herein, we reported a facile fabrication method to prepare a multiaxial low-density polyethylene (LDPE)/carbon fibers (CFs) tube with bidirectional controllable electrical conductivity and sensitive strain-responsive performance via rotation extrusion technology. The multidimensional helical flow is confirmed in the reverse rotation extrusion, and the CFs readily respond to the flow field leading to a multiaxial orientation in the LDPE matrix. In contrast to uniaxial LDPE/CF composites, which perform a "head to head" conjunction, multiaxial-orientated CF networks exhibit a unique multilayer structure in which the CFs with distinct orientation direction intersect in the interface, endowing the LDPE/CF composites with a low percolation threshold (15 wt %) to those of the uniaxial ones (∼35 wt %). The angles between two axes play a vital role in determining the density of the conductive networks in the interface, which is predominant in tuning the bending-responsive behaviors with a gauge factor range from 12.5 to 56.3 and the corresponding linear respond region from ∼15 to ∼1%. Such a superior performance of conductive LDPE/CF tube confirms that the design of multiaxial orientation paves a novel way to facile fabrication of advanced cost-effective CF-based smart materials, shedding light on promising applications such as smart materials and intelligent engineering monitoring.

  18. Compatibility of polyamide 6.6 and low density polyethylene polymeric blend using electron beam ionizing radiation

    International Nuclear Information System (INIS)

    Feitosa, Marcos Antonio Fernandes

    2008-01-01

    The plastic industry has recognized that mixture of polymers, called polymeric blends, yields new materials with improve properties and better features of those of the polymer blended. In most of the cases, blends are formed by immiscible components presenting separated phases, micro-structures or morphologies. One of the main factors for good mechanical performance is the interfacial adhesion of the blend components. The improvement of miscibility between the polymer components and the enhancement of blend performance is denominated of compatibility. This compatibility can be achieved by chemical methods or using ionizing radiation. The present work has as a main objective the study of the effect of the ionizing radiation from electron beam in the compatibility of the polyamide (PA) 6.6 and low density polyethylene (LDPE) 75%/25% wt blend, in the range of applied doses from 50 to 250 kGy. The compatibility effect was evaluated by mechanical test, which has shown improvement in the tensile strength and hardness properties and a reduction of the impact resistant. This mechanical behavior can be considered as a combination effect of the cross-linking, induced in the molecular structure on the polymers, and the increase of the miscibility of the blend components. The degree of compatibility was evaluated by the behavior of the glass transition temperatures (T g ) for the blend components obtained by dynamic mechanical analysis (DMA) measurements. The results have shown that the values of T g for PA 6.6 and LDPE get near by 8 deg C showing that the ionizing radiation have promoted a compatibility effect on the irradiated blend. (author)

  19. Preliminary evaluation of the immobilization of simulated evaporator concentrate waste in low density polyethylene by extrusion process

    International Nuclear Information System (INIS)

    Cota, Stela; Oliveira, Tania Valeria S. de; Senne Junior, Murillo; Pacheco, Graziella

    2007-01-01

    Simulated evaporator concentrate was prepared by pre-treating sodium borate with calcium hydroxide to produce an insoluble borate salt. The resultant solid waste was blended by extrusion with virgin low density polyethylene (LDPE) in the proportion of 30 wt%. Samples were prepared to evaluate homogeneity, mechanical strength and leaching behavior. The homogeneity of each sample individually and in consecutive samples was indirectly estimated by sectioning each sample in four pieces and submitting each piece to density determination (ASTM standard D-792). Mechanical strength was evaluated through determination of compressive strength (ASTM standard D-695), and the results were compared to the value for the pure polymer and with the limit established by CNEN standard NN-6.09 for cement waste products. Samples were also tested for leaching by accelerated leaching test (ASTM standard C1308). Results showed a good homogeneity. Standard deviations of the density measurements were less than 1% for a single sample and less than 6% considering 3 samples. Polymer compressive strength at yield point and at 5% and 10% strain have increased after the mixture with the simulated waste, indicating an increase on the material strength. Estimated compressive strength was above CNEN standard limit for cement waste products if 5% strain could be considered a reasonable limit to assure structural integrity of the material. Cumulated leaching fraction after 11 days of accelerated leaching test was found to be below 10%, and diffusion coefficient was estimated as 9.06 x 10 -10 cm 2 /s, with deviation of 8.3%. (author)

  20. Preliminary evaluation of the immobilization of simulated evaporator concentrate waste in low density polyethylene by extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Stela; Oliveira, Tania Valeria S. de; Senne Junior, Murillo; Pacheco, Graziella [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: sdsc@cdtn.br

    2007-07-01

    Simulated evaporator concentrate was prepared by pre-treating sodium borate with calcium hydroxide to produce an insoluble borate salt. The resultant solid waste was blended by extrusion with virgin low density polyethylene (LDPE) in the proportion of 30 wt%. Samples were prepared to evaluate homogeneity, mechanical strength and leaching behavior. The homogeneity of each sample individually and in consecutive samples was indirectly estimated by sectioning each sample in four pieces and submitting each piece to density determination (ASTM standard D-792). Mechanical strength was evaluated through determination of compressive strength (ASTM standard D-695), and the results were compared to the value for the pure polymer and with the limit established by CNEN standard NN-6.09 for cement waste products. Samples were also tested for leaching by accelerated leaching test (ASTM standard C1308). Results showed a good homogeneity. Standard deviations of the density measurements were less than 1% for a single sample and less than 6% considering 3 samples. Polymer compressive strength at yield point and at 5% and 10% strain have increased after the mixture with the simulated waste, indicating an increase on the material strength. Estimated compressive strength was above CNEN standard limit for cement waste products if 5% strain could be considered a reasonable limit to assure structural integrity of the material. Cumulated leaching fraction after 11 days of accelerated leaching test was found to be below 10%, and diffusion coefficient was estimated as 9.06 x 10{sup -10} cm{sup 2}/s, with deviation of 8.3%. (author)

  1. Morphological and mechanical properties of polyamide 6/linear low density polyethylene blend compatibilized by electron-beam initiated mediation process

    International Nuclear Information System (INIS)

    Shin, Boo Young; Han, Do Hung

    2014-01-01

    The aim of this study was to compatibilize immiscible polyamide 6 (PA6)/linear low density polyethylene (LLDPE) blend by using electron-beam initiated mediation process. Glycidyl methacrylate (GMA) was chosen as a mediator for cross-copolymerization at the interface between PA6 and LLDPE. The exposure process was carried out to initiate cross-copolymerization by the medium of GMA at the interface between PA and LLDPE. The mixture of the PA6/LLDPE/GMA was prepared by using a twin-screw extruder, and then the mixture was exposed to electron-beam radiation at various doses at room temperature. To investigate the results of this compatibilization strategy, the morphological and mechanical properties of the blend were analyzed. Morphology study revealed that the diameters of the dispersion particles decreased and the interfacial adhesion increased with respect to irradiation doses. The elongation at break of the blends increases significantly with increasing irradiation dose up to 100 kGy while the tensile strength and the modulus increased nonlinearly with increasing irradiation dose. The reaction mechanisms of the mediation process with the GMA mediator at the interface between PA6 and LLDPE were estimated. - Highlights: • PA6/LLDPE blend was compatibilized by the electron-beam initiated mediation process. • Interfacial adhesion was significantly enhanced by the radiation initiated cross-copolymerization. • The elongation at break of blend irradiated at 100 kGy was 4 times higher than PA6. • The GMA as a mediator played a key role in the electron-beam initiated mediation process

  2. Rheological characterization of LDPE{sub Al} (low density polyethylene and aluminum) e HDPE (high density polyethylene); Caracterizacao das propriedades reologicas da mistura LDPE{sub Al} (polietileno de baixa densidade e aluminio) e HDPE (polietileno de alta densidade)

    Energy Technology Data Exchange (ETDEWEB)

    Santa Marinha, Ana Beatriz Abreu; Pacheco, Elen Beatriz Acordi Vasques; Monteiro, Elisabeth Ermel da Costa [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Macromoleculas

    2008-07-01

    The long life packaging contains paper, polyethylene and aluminum for packaging of food. A few part of total amount produced is recycled and another is discharged in landfills in Brazil. The low density polyethylene and aluminum (LDPE{sub Al}) was obtained from recycling this packaging. The rheological properties of the blends were intermediate to ones of the pure polymers. In a general way, the rheological properties were not modified by the aluminum presence. (author)

  3. Assessment of low density polyethylene characteristics for hazardous waste immobilization; Avaliacao das caracteristicas do polietileno de baixa densidade visando a imobilizacao de rejeitos perigosos

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Stela; Carvalho, Larissa Lara de; Pacheco, Graziella Rajao Cota; Oliveira, Tania Valeria de; Senne Junior, Murillo; Pacheco, Raquel R. Janot [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil)]. E-mail: sdsc@cdtn.br

    2005-07-01

    This paper analyses the properties of low density polyethylene (LDPE) to allow choosing the more suitable to be used as matrices for radioactive and hazardous waste immobilization. Four virgin and recycled LDPE, with different melting index, were evaluated by extrusion and compressive strength tests. A preliminary immobilization test has been carried out using a simulated waste and one of the evaluated polymers and the homogeneity of the final waste product was determinate by the analysis of the material density. (author)

  4. Correlation between Onset Oxidation Temperature (OOT) and Fourier Transform Infrared Spectroscopy (FTIR) for monitoring the restabilization of Recycled Low-density Polyethylene (LDPE)

    Energy Technology Data Exchange (ETDEWEB)

    Ruvolo-Filho, Adhemar; Pelozzi, Tadeu Luiz Alonso, E-mail: adhemar@power.ufscar.br [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Quimica

    2013-07-01

    In this work a new method was developed for monitoring the oxidative stability of restabilized and non-restabilized low-density polyethylene (LDPE) during multiple extrusion cycles. The method is based on correlations between Fourier Transform Infrared Spectroscopy (FTIR) and Onset Oxidation Temperature (OOT). Non-linear calibration curves correlating the concentration of primary or secondary antioxidants and the OOT values were obtained. (author)

  5. Electrically and Thermally Conductive Low Density Polyethylene-Based Nanocomposites Reinforced by MWCNT or Hybrid MWCNT/Graphene Nanoplatelets with Improved Thermo-Oxidative Stability

    OpenAIRE

    Sandra Paszkiewicz; Anna Szymczyk; Daria Pawlikowska; Jan Subocz; Marek Zenker; Roman Masztak

    2018-01-01

    In this paper, the electrical and thermal conductivity and morphological behavior of low density polyethylene (LDPE)/multi-walled carbon nanotubes (MWCNTs) + graphene nanoplatelets (GNPs) hybrid nanocomposites (HNCs) have been studied. The distribution of MWCNTs and the hybrid of MWCNTs/GNPs within the polymer matrix has been investigated with scanning electron microscopy (SEM). The results showed that the thermal and electrical conductivity of the LDPE-based nanocomposites increased along wi...

  6. The relationship between sol fraction and radiation dose in radiation crosslinking of low-density polyethylene (LDPE)/ethylenevinylacetate copolymer (EVA) blend

    International Nuclear Information System (INIS)

    Zhang, W.X.; Liu, Y.T.; Sun, J.Z.

    1990-01-01

    In this paper, two different methods were used to prepare the blend of low-density polyethylene (LDPE) and ethylene vinyl acetate copolymer (EVA). One of them was mechanical blending, and the other was solution blending. The relationship between sol fraction and radiation dose of different weight ratio polymer blends has been studied. The method to calculate the β b value of polymer blend system (LDPE/EVA) has been established. (author)

  7. Surface modification of polyethylene films using atmospheric ...

    African Journals Online (AJOL)

    An atmospheric-pressure plasma jet (APPJ) is used to increase the wettability of polyethylene polymer films. Reduction in contact angle from 94.32 to 58.33 degrees was measured for treatment times of 1 - 5 seconds. Contact angle reductions of PE as a function of treatment time with APPJ and PE surface at various oxygen ...

  8. Sorption of Binary Mixtures of Toluene plus Lower Aliphatic Alcohols C1 – C6 in Low-Density Polyethylene

    Czech Academy of Sciences Publication Activity Database

    Randová, A.; Bartovská, L.; Hovorka, Š.; Izák, Pavel; Friess, K.; Janků, J.

    2011-01-01

    Roč. 119, č. 3 (2011), s. 1781-1787 ISSN 0021-8995 R&D Projects: GA ČR GA104/08/0600 Institutional research plan: CEZ:AV0Z40720504 Keywords : swelling * polyethylene (LDPE) * membrane Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.289, year: 2011

  9. Research physic-mechanical properties of composite materials on the base of peeled veneer and low density polyethylene

    Science.gov (United States)

    Ibragimov, Aleksandr; Vasilkin, Andrey; Fedotov, Aleksandr

    2017-10-01

    Use film of LDPE as thermoplastic binder for production of plywood is proposed. Results of physic-mechanical properties of plywood based on the LDPE film of different thicknesses in comparison with conventional thermosetting synthetic binder are presented.

  10. Investigation of photo-biodegradation of starch-filled polyethylene films under the environment conditions of Tehran

    International Nuclear Information System (INIS)

    Naeimian, F.; Khoylou, F.; Sheikh, N.; Akhavan, A.; Hassanpour, S.; Sohrabpour, M.

    2006-01-01

    In this work biodegradable polymers have been formulated for packaging purposes and with a view to reduce the environmental accumulation of plastic waste. Degradation of the polymers under the specific weathering conditions of Tehran was studied. In this work low-density polyethylene was formulated with two wheat starch concentrations, maleic anhydride, glycerol as well as a pro-oxidant system of oleic acid, benzoyl peroxide and ferric stearate. The formulated master batches were mixed by using a laboratory two-roll mill at 190 d ig C prepared master batches were mixed with the commercial low-density polyethylene to prepare compounds 1 and 2 containing 1.2 and 6.4 percents wheat starch. The low-density polyethylene control films as well as the formulated compounds were compression moulded in a hot press at 130 d ig C films were subjected to three general conditions of atmospheric exposure, buried in soil and combined conditions of soil burial/ atmospheric exposure. The three environmental conditions impact upon the formulated and control films were investigated through tensile strength, elongation-at-break, carbonyl index, water absorption, weight loss as well as SEM analysis. The microbial investigation was followed by growing the Penicillium Asymmetrica, which had the main population in microbial flora of the soil, on formulated and control films. The studies revealed that the incorporation of this pro-oxidant system with the addition of 6.4% wheat starch enhance the degradation rate of commercial low-density polyethylene films to a significant degree

  11. Effect of Heat Drawing Process on Mechanical Properties of Dry-Jet Wet Spun Fiber of Linear Low Density Polyethylene/Carbon Nanotube Composites

    Directory of Open Access Journals (Sweden)

    Jong Won Kim

    2017-01-01

    Full Text Available Polyethylene is one of the most commonly used polymer materials. Even though linear low density polyethylene (LLDPE has better mechanical properties than other kinds of polyethylene, it is not used as a textile material because of its plastic behavior that is easy to break at the die during melt spinning. In this study, LLDPE fibers were successfully produced with a new approach using a dry-jet wet spinning and a heat drawing process. The fibers were filled with carbon nanotubes (CNTs to improve the strength and reduce plastic deformation. The crystallinity, degree of orientation, mechanical properties (strength to yield, strength to break, elongation at break, and initial modulus, electrical conductivity, and thermal properties of LLDPE fibers were studied. The results show that the addition of CNTs improved the tensile strength and the degree of crystallinity. The heat drawing process resulted in a significant increase in the tensile strength and the orientation of the CNTs and polymer chains. In addition, this study demonstrates that the heat drawing process effectively decreases the plastic deformation of LLDPE.

  12. Pre-oxidation of low-density polyethylene (LDPE) by ultraviolet light (UV) promotes enhanced degradation of LDPE in soil.

    Science.gov (United States)

    Tribedi, Prosun; Dey, Samrat

    2017-11-09

    Polyethylene represents nearly 64% of all the synthetic plastics produced and are mainly used for domestic and industrial applications. Their extensive use poses a serious environmental threat because of their non-biodegradable nature. Among all the polyethylene remediation strategies, in situ bioremediation happens to be the safest and efficient one. In the current study, efforts had been given to compare the extent of LDPE degradation under UV-treated and UV-untreated conditions by soil microcosm. Landfill soil was collected and UV-treated and UV-untreated LDPE were added separately to the soil following incubation under similar conditions. Electron microscopic images as well as the weight loss and the tensile strength results clearly revealed that UV-treated LDPE showed better degradation than the non-treated ones in soil. To elucidate the mechanism of this enhanced biodegradation, the bond spectra of differentially treated LDPE were analyzed by FTIR. The results obtained from bond spectra studies revealed that UV treatment increases both carbonyl and terminal double-bond index of the LDPE, thereby making it highly susceptible for microbial degradation. Moreover, incubation of UV-treated LDPE with soil favors better adherence of metabolically active and significantly higher number of microorganisms on it. Taken together, all these results demonstrate the higher microbial association and their better metabolic potential to the UV-treated LDPE that lead to enhanced degradation of the LDPE by the soil microorganisms.

  13. Grafting of polyethylene films with acrylic acid and acrylonitril using gamma radiation

    International Nuclear Information System (INIS)

    Ajji, Z.; Al-Nesr, E.

    2003-12-01

    Acrylic acid (AAc) and acrylonitrile (AN) and their binary mixtures were graft copolymerized onto low density polyethylene (LDPE) films using gamma irradiation. The effects of different parameters on the graft yield were studies such as monomer concentration, inhibitor concentration, and irradiation dose. The obtained grafted films were characterized using FTIR spectroscopy, thermal gravimetry, and differential scanning calorimetry. Water uptake and the ion uptake were also evaluated, and the ability of grafted films to uptake heavy ions such as Ni 2+ and Cu 2+ was discussed. (author)

  14. Comparative study of two methods of analysis crystallinity, x-ray and DSC, using a linear low density polyethylene (LLDPE) injected, irradiated by gamma radiation

    International Nuclear Information System (INIS)

    Oliveira, Ana C.F. de; Ferreto, Helio F.R.; Parra, Duclerc F.; Lugao, Ademar B.

    2015-01-01

    The linear low density polyethylene (LLDPE) is a linear polymer chain with short chain branching. In this work, the LLDPE was irradiated in "6"0Co gamma source with 2000 kCi of activity, in presence of air, with doses of 5, 10, 20, 50 or 100 kGy, at about 5 kGy.h-1 dose rate, at room temperature. After irradiation, the samples were heated for 60 min at 100 deg C to promote recombination and annihilation of residual radicals. LLDPE injected and irradiated samples were characterized to identity the effects of terminal degradation, scission and crosslinking occurred in each dose. In the radiation process has changes in the crystallization and thus it is possible to compare the methods to obtain the percentage of crystallization of PELDB by DSC and X-ray. (author)

  15. Effects of Kenaf Loading on Processability and Properties of Linear Low-Density Polyethylene/Poly (Vinyl Alcohol/Kenaf Composites

    Directory of Open Access Journals (Sweden)

    Ai Ling Pang

    2015-09-01

    Full Text Available This study was conducted to evaluate the possibility of utilizing kenaf (KNF in LLDPE/PVOH to develop a new thermoplastic composite. The effect of KNF loading on the processability and mechanical, thermal and water absorption properties of linear low-density polyethylene/poly (vinyl alcohol/kenaf (LLDPE/PVOH/KNF composites were investigated. Composites with different KNF loadings (0, 10, 20, 30, and 40 phr were prepared using a Thermo Haake Polydrive internal mixer at a temperature of 150 °C and rotor speed of 50 rpm for 10 min. The results indicate that the stabilization torque, tensile modulus, water uptake, and thermal stability increased, while tensile strength and elongation at break decreased with increasing filler loading. The tensile fractured surfaces observed by scanning electron microscopy (SEM supported the deterioration in tensile properties of the LLDPE/PVOH/KNF composites with increasing KNF loading.

  16. Electrically and Thermally Conductive Low Density Polyethylene-Based Nanocomposites Reinforced by MWCNT or Hybrid MWCNT/Graphene Nanoplatelets with Improved Thermo-Oxidative Stability

    Directory of Open Access Journals (Sweden)

    Sandra Paszkiewicz

    2018-04-01

    Full Text Available In this paper, the electrical and thermal conductivity and morphological behavior of low density polyethylene (LDPE/multi-walled carbon nanotubes (MWCNTs + graphene nanoplatelets (GNPs hybrid nanocomposites (HNCs have been studied. The distribution of MWCNTs and the hybrid of MWCNTs/GNPs within the polymer matrix has been investigated with scanning electron microscopy (SEM. The results showed that the thermal and electrical conductivity of the LDPE-based nanocomposites increased along with the increasing content of carbon nanofillers. However, one could observe greater improvement in the thermal and electrical conductivity when only MWCNTs have been incorporated. Moreover, the improvement in tensile properties and thermal stability has been observed when carbon nanofillers have been mixed with LDPE. At the same time, the increasing content of MWCNTs and MWCNTs/GNPs caused an increase in the melt viscosity with only little effect on phase transition temperatures.

  17. Electrically and Thermally Conductive Low Density Polyethylene-Based Nanocomposites Reinforced by MWCNT or Hybrid MWCNT/Graphene Nanoplatelets with Improved Thermo-Oxidative Stability.

    Science.gov (United States)

    Paszkiewicz, Sandra; Szymczyk, Anna; Pawlikowska, Daria; Subocz, Jan; Zenker, Marek; Masztak, Roman

    2018-04-22

    In this paper, the electrical and thermal conductivity and morphological behavior of low density polyethylene (LDPE)/multi-walled carbon nanotubes (MWCNTs) + graphene nanoplatelets (GNPs) hybrid nanocomposites (HNCs) have been studied. The distribution of MWCNTs and the hybrid of MWCNTs/GNPs within the polymer matrix has been investigated with scanning electron microscopy (SEM). The results showed that the thermal and electrical conductivity of the LDPE-based nanocomposites increased along with the increasing content of carbon nanofillers. However, one could observe greater improvement in the thermal and electrical conductivity when only MWCNTs have been incorporated. Moreover, the improvement in tensile properties and thermal stability has been observed when carbon nanofillers have been mixed with LDPE. At the same time, the increasing content of MWCNTs and MWCNTs/GNPs caused an increase in the melt viscosity with only little effect on phase transition temperatures.

  18. Effect of Bagasse Chemical Pulping and Coupling Agent on the Physical - Mechanical Properties of Composites Based on Bagasse pulp/Low density polyethylene

    Directory of Open Access Journals (Sweden)

    maryam allahdadi

    2016-12-01

    Full Text Available In this research, effect of reinforcing bagasse pulp and raw bagasse fibers and applying coupling agent MAPE (Maleic Anhydride Polyethylene on physical-mechanical properties of low density polyethylene (LDPE composites were studided. Fresh bagasse were collected from an experimental field in Khuzestan and after investigating anatomy and chemical properties of Different pulp fibers including monoethanolamine (MEA bagasse pulp, alkaline sulfite-anthraquinone (AS bagasse pulp, bleached soda (BS bagasse pulp, unbleached soda (UNS bagasse pulp and raw bagasse fibers (B were prepared. Then, composites with 30wt.% fiber content were manufactured by twin-screw extrusion followed by compression molding processing. The mechanical and physical properties of these composites were analyzed and compared. Results revealed that the chemical pulping dissolved a fraction of lignin and hemicelluloses so that the linkage potential and aspect ratio of bagasse fibers was improved and consequently, as compared with the raw bagasse fibers, bagasse pulp fibers have better reinforcing capability. The best overall properties were achieved with MEA and AS/AQ fibers. Addition of 5% (wt/wt of coupling agent MAPE resulted in a significant enhancement in the tensile strength, tensile modulus and impact strength in line with the improvement of the fiber-matrix interfacial adhesion making more effective the transfer of stress from the matrix to the rigid reinforcement.

  19. The Effect of wheat straw particle size on the mechanical and water absorption properties of wheat straw/low density polyethylene biocomposites for packaging applications

    Directory of Open Access Journals (Sweden)

    Behjat Tajeddin

    2017-08-01

    Full Text Available Natural composites with biodegradability properties can be used as a renewable alternative to replacing conventional plastics. Thus, to reduce the plastics applications in the packaging industry, biocomposites content of wheat straw (with 40, 100, 140 mesh as a natural biodegradable composite and low density polyethylene (LDPE as a common synthetic polymer in the packaging industry were prepared and characterized by the mechanical and water absorption properties. Polyethylene-graft-maleic anhydride was used as a compatibilizer material. Morphology of wheat straw flour was studied by optical microscope to obtain the aspect ratio (L/D. The tensile and flexural tests were applied for determining mechanical properties and scanning electron microscope (SEM was used for particles distribution and sample structures. The water absorption of the samples was calculated by weight difference. The results indicated that the particle size of wheat straw four and the L/D amount are Significantly affected on the tensile strength and water absorption of the samples. However, the effect of wheat sraw particle size on the flexural strength was not significant. Overall conclusions show that by increasing the particle size of the filler (wheat straw, can prepare the biocomposite with better tensile strength and less water absorption compared with smaller particle size.

  20. Substrate removal kinetics in high-rate upflow anaerobic filters packed with low-density polyethylene media treating high-strength agro-food wastewaters.

    Science.gov (United States)

    Rajagopal, Rajinikanth; Torrijos, Michel; Kumar, Pradeep; Mehrotra, Indu

    2013-02-15

    The process kinetics for two upflow anaerobic filters (UAFs) treating high strength fruit canning and cheese-dairy wastewaters as feed were investigated. The experimental unit consisted of a 10-L (effective volume) reactor filled with low-density polyethylene media. COD removal efficiencies of about 80% were recorded at the maximum OLRs of 19 and 17 g COD L(-1) d(-1) for the fruit canning and cheese-dairy wastewaters, respectively. Modified Stover-Kincannon and second-order kinetic models were applied to data obtained from the experimental studies in order to determine the substrate removal kinetics. According to Stover-Kincannon model, U(max) and K(B) values were estimated as 109.9 and 109.7 g L(-1) d(-1) for fruit canning, and 53.5 and 49.7 g L(-1) d(-1) for cheese dairy wastewaters, respectively. The second order substrate removal rate k(2(s)) was found to be 5.0 and 1.93 d(-1) respectively for fruit canning and cheese dairy wastewaters. As both these models gave high correlation coefficients (R(2) = 98-99%), they could be used in predicting the behaviour or design of the UAF. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Tensile properties and water absorption assessment of linear low-Density Polyethylene/Poly (Vinyl Alcohol)/Kenaf composites: effect of eco-friendly coupling agent

    Science.gov (United States)

    Pang, A. L.; Ismail, H.; Abu Bakar, A.

    2018-02-01

    Linear low-density polyethylene (LLDPE)/poly (vinyl alcohol) (PVOH) filled with untreated kenaf (UT-KNF) and eco-friendly coupling agent (ECA)-treated kenaf (ECAT-KNF) were prepared using ThermoHaake internal mixer, respectively. Filler loadings of UT-KNF and ECAT-KNF used in this study are 10 and 40 parts per hundred parts of resin (phr). The effect of ECA on tensile properties and water absorption of LLDPE/PVOH/KNF composites were investigated. Field emission scanning electron microscopy (FESEM) analysis was applied to visualize filler-matrix adhesion. The results indicate LLDPE/PVOH/ECAT-KNF composites possess higher tensile strength and tensile modulus, but lower elongation at break compared to LLDPE/PVOH/UT-KNF composites. The morphological studies of tensile fractured surfaces using FESEM support the increment in tensile properties of LLDPE/PVOH/ECAT-KNF composites. Nevertheless, LLDPE/PVOH/UT-KNF composites reveal higher water absorption compared to LLDPE/PVOH/ECAT-KNF composites.

  2. Effect of wood filler treatment and EBAGMA compatibilizer on morphology and mechanical properties of low density polyethylene/olive husk flour composites

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available This paper deals with plastic-wood composites based on low density polyethylene (LDPE and olive husk flour (OHF. The problem of incompatibility between the hydrophilic wood filler and the LDPE hydrophobic matrix was treated by two methods: a chemical modification of the olive husk flour with maleic anhydride to esterify the free hydroxyl groups of the wood components and the use of a compatibilizer agent, i.e. an ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA terpolymer. The changes in the structure, the morphology, and the properties resulting from these treatments were followed by various techniques, especially FTIR spectroscopy, scanning electron microscopy (SEM, tensile measurements and water absorption. The experimental results indicated that both methods, i.e. the chemical treatment of the olive husk flour with maleic anhydride and the inclusion of EBAGMA terpolymer, improved the interactions between the two composite components and promoted better dispersion of the filler in the matrix. Moreover, ultimate tensile properties were also increased. However, the use of EBAGMA terpolymer as compatibilizer produced better enhancement of the properties of LDPE/OHF composites compared to those treated with maleic anhydride.

  3. Effect of high energy electron beam (10 MeV) on specific heat capacity of low-density polyethylene/hydroxyapatite nano-composite

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, Z., E-mail: zhr_soltani@yahoo.com [Health Physics and Radiation Dosimetry Research Laboratory, Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Ziaie, F. [Radiation Application Research School, Nuclear Science & Technology Research Institute, Tehran (Iran, Islamic Republic of); Ghaffari, M. [Polymer Group, Golestan University, Golestan (Iran, Islamic Republic of); Beigzadeh, A.M. [Radiation Application Research School, Nuclear Science & Technology Research Institute, Tehran (Iran, Islamic Republic of)

    2017-02-01

    In the present work, thermal properties of low density polyethylene (LDPE) and its nano composites are investigated. For this purpose LDPE reinforced with different weight percents of hydroxyapatite (HAP) powder which was synthesized via hydrolysis method are produced. The samples were irradiated with 10 MeV electron beam at doses of 75 to 250 kGy. Specific heat capacity measurement have been carried out at different temperatures, i.e. 25, 50, 75 and 100 °C using modulated temperature differential scanning calorimetry (MTDSC) apparatus and the effect of three parameters include of temperature, irradiation dose and the amount of HAP nano particles as additives on the specific heat capacity of PE/HAP have been investigated precisely. The MTDSC results indicate that the specific heat capacity have decreased by addition of nano sized HAP as reinforcement for LDPE. On the other hand, the effect of radiation dose is reduction in the specific heat capacity in all materials including LDPE and its nano composites. The HAP nano particles along with cross-link junctions due to radiation restrain the movement of the polymer chains in the vicinity of each particle and improve the immobility of polymer chains and consequently lead to reduction in specific heat capacity. Also, the obtained results confirm that the radiation effect on the specific heat capacity is more efficient than the reinforcing effect of nano-sized hydroxyapatite.

  4. Investigation of space charge distribution of low-density polyethylene/GO-GNF (graphene oxide from graphite nanofiber) nanocomposite for HVDC application.

    Science.gov (United States)

    Kim, Yoon Jin; Ha, Son-Tung; Lee, Gun Joo; Nam, Jin Ho; Ryu, Ik Hyun; Nam, Su Hyun; Park, Cheol Min; In, Insik; Kim, Jiwan; Han, Chul Jong

    2013-05-01

    This paper reported a research on space charge distribution in low-density polyethylene (LDPE) nanocomposites with different types of graphene and graphene oxide (GO) at low filler content (0.05 wt%) under high DC electric field. Effect of addition of graphene oxide or graphene, its dispersion in LDPE polymer matrix on the ability to suppress space charge generation will be investigated and compared with MgO/LDPE nanocomposite at the same filler concentration. At an applied electric field of 80 kV/mm, a positive packet-like charge was observed in both neat LDPE, MgO/LDPE, and graphene/LDPE nanocomposites, whereas only little homogenous space charge was observed in GO/LDPE nanocomposites, especially with GO synthesized from graphite nano fiber (GNF) which is only -100 nm in diameter. Our research also suggests that dispersion of graphene oxide particles on the polymer matrix plays a significant role to the performance of nanocomposites on suppressing packet-like space charge. From these results, it is expected that nano-sized GO synthesized from GNF can be a promising filler material to LDPE composite for HVDC applications.

  5. Shape Memory Polymer Composites of Poly(styrene-b-butadiene-b-styrene Copolymer/Liner Low Density Polyethylene/Fe3O4 Nanoparticles for Remote Activation

    Directory of Open Access Journals (Sweden)

    Yongkun Wang

    2016-11-01

    Full Text Available Magnetically sensitive shape memory poly(styrene-b-butadiene-b-styrene copolymer (SBS/liner low density polyethylene (LLDPE composites filled with various contents of Fe3O4 nanoparticles were prepared. The influence of the Fe3O4 nanoparticles content on the thermal properties, mechanical properties, fracture morphology, magnetic behavior, and shape memory effect of SBS/LLDPE/Fe3O4 composites was systematically studied in this paper. The results indicated that homogeneously dispersed Fe3O4 nanoparticles ensured the uniform heat generation and transfer in the alternating magnetic field, and endowed the SBS/LLDPE/Fe3O4 composites with an excellent magnetically responsive shape memory effect. When the shape memory composites were in the alternating magnetic field (f = 60 kHz, H = 21.21 kA·m−1, the best shape recovery ratio reached 99%, the shape retention ratio reached 99.4%, and the shape recovery speed increased significantly with the increment of Fe3O4 nanoparticles. It is anticipated that tagging products with this novel shape memory composite is helpful for the purpose of an intravascular delivery system in Micro-Electro-Mechanical System (MEMS devices.

  6. Engineering functional nanothin multilayers on food packaging: ice-nucleating polyethylene films.

    Science.gov (United States)

    Gezgin, Zafer; Lee, Tung-Ching; Huang, Qingrong

    2013-05-29

    Polyethylene is the most prevalent plastic and is commonly used as a packaging material. Despite its common use, there are not many studies on imparting functionalities to those films which can make them more desirable for frozen food packaging. Here, commercial low-density polyethylene (LDPE) films were oxidized by UV-ozone (UVO) treatment to obtain a negatively charged hydrophilic surface to allow fabrication of functional multilayers. An increase in hydrophilicity was observed when films were exposed to UVO for 4 min and longer. Thin multilayers were formed by dipping the UVO-treated films into biopolymer solutions, and extracellular ice nucleators (ECINs) were immobilized onto the film surface to form a functional top layer. Polyelectrolyte adsorption was studied and confirmed on silicon wafers by measuring the water contact angles of the layers and investigating the surface morphology via atomic force microscopy. An up to 4-5 °C increase in ice nucleation temperatures and an up to 10 min decrease in freezing times were observed with high-purity deionized water samples frozen in ECIN-coated LDPE films. Films retained their ice nucleation activity up to 50 freeze-thaw cycles. Our results demonstrate the potential of using ECIN-coated polymer films for frozen food application.

  7. Photocrosslinker technology: An antimicrobial efficacy of cinnamaldehyde cross-linked low-density polyethylene (Cin-C-LDPE) as a novel food wrapper.

    Science.gov (United States)

    Manukumar, H M; Umesha, S

    2017-12-01

    In recent years much attention has been devoted to active packaging technologies that offer new opportunities for the food industry and food preservation. The spoilage of food products during post process handling leads to food contamination and causes life-threatening food-borne illness. The methicillin-resistant Staphylococcus aureus (MRSA) 090 is one of the food-borne pathogens associated with food poisoning that leads to an outbreak of perilous human infections worldwide. The development of resistance in bacteria and diffusion of coated synthetic preservatives into food are the major problem in food packaging industries. In the present work, we have developed a new food wrap method by cross-linking cinnamaldehyde on low-density polyethylene (Cin-C-LDPE) using novel photocrosslinker technology. The cinnamaldehyde showed potent antimicrobial activity (145mg/mL of MIC) against MRSA 090 and radical scavenging activity (RSA). The cinnamaldehyde was successfully cross-linked to LDPE and exhibited excellent antibiofilm properties against MRSA090 compared to bare LDPE. This positive interaction of developed Cin-C-LDPE against MRSA090 biofilm was confirmed by SEM and FT-IR studies, and results showed the damaged cell membrane architecture, inturn abridged adherence of MRSA090. The Cin-C-LDPE wrapped chicken, mutton, cheese, and grapes showed 2.5±0.15 log MRSA 090 reduction at the end of 10th day compared to the bare LDPE wrapped food samples. This clearly concludes that for the first time we have developed a novel Cin-C-LDPE food wrap technology effectively involved in biocidal activity against MRSA090. Applying this new strategy to develop food wrap containing nontoxic natural antimicrobial to target cell membrane components is the upcoming challenging and promising research gap remains in the food packaging industry for the future world. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Blending of Low-Density Polyethylene and Poly-Lactic Acid with Maleic Anhydride as A Compatibilizer for Better Environmentally Food-Packaging Material

    Science.gov (United States)

    Setiawan, A. H.; Aulia, F.

    2017-05-01

    The common conventional food packaging materialsare using a thin layer plastic or film, which is made of a synthetic polymer, such as Low-Density Poly Ethylene (LDPE). However, the use of these polymers hasan adverse impact on the environment, because the synthetic polymersare difficult to degrade naturally. Poly-Lactic Acid (PLA) is a biodegradable polymer that can be substituted to synthetic polymers. Since LDPE and PLA have a difference in polarity, therefore the first step of research is to graft them with maleic anhydride (MAH) for increasing the properties of its miscibility. The interaction between them is confirmed by FTIR; whereas the environment issueis characterized by the water adsorption and biodegradability. The FTIR spectra indicated that there had been an interaction between LDPE and MAH and LDPE/LDPE-g-MAH/PLA blend. Increasing PLA content in the blend affected to the increasing in their water absorption and biodegradable. Poly-blend with 20% PLA content was the optimum composition for environmentally food packaging.

  9. Electron beam induced graft-polymerization of methyl methacrylate onto polyethylene films at high dose rates

    International Nuclear Information System (INIS)

    Mori, Koji; Koshiishi, Kenji; Masuhara, Ken-ichi

    1991-01-01

    Electron beam induced graft-polymerization by the mutual irradiation technique of methyl methacrylate on the surface of low density polyethylene films (LD) and high density polyethylene films (HD) was investigated at high dose rates over 10 Mrad per second. Graft-polymerization mechanisms were discussed on the basis of O 2 permeability, tensile strength, elongation at break, and surface tension of the grafted films. As the degree of grafting increased, the O 2 permeability of LD decreased, while that of HD little changed at the grafting up to 4 ∼ 5 %. This indicates that the grafting occurred in the amorphous regions for LD and occurred in the amorphous regions in the neighborhood of crystalline regions for HD. For HD, when the degree of the grafting surpassed 4 ∼ 5 %, the O 2 permeability, tensile strength, elongation at break, and surface tension decreased with an increase in the degree of grafting. It was assumed that rapid grafting in the amorphous regions in the neighborhood of crystalline regions caused the increase in local temperature by the heat of polymerization, and the viscosity of polyethylene in the amorphous regions decreased with an increase in temperature. As a result, the graft chains, which formed micro domain structure, condensed in the amorphous regions and the domain increased in size. (author)

  10. 76 FR 54791 - Polyethylene Terephthalate (PET) Film From Korea

    Science.gov (United States)

    2011-09-02

    ... Terephthalate (PET) Film From Korea Determination On the basis of the record \\1\\ developed in the subject five... order on polyethylene terephthalate (PET) film from Korea would not be likely to lead to continuation or... was given by posting copies of the notice in the Office of the Secretary, U.S. International Trade...

  11. Effect of solubility parameter of monomers on electron beam induced graft-polymerization onto polyethylene films

    International Nuclear Information System (INIS)

    Mori, Koji; Koshiishi, Kenji; Masuhara, Ken-ichi

    1991-01-01

    Electron beam induced graft-polymerization by the mutual irradiation technique of monomers with different solubility parameters δ onto low density polyethylene films (LDPE) and high density polyethylene films (HDPE) were investigated at high dose rates (25 Mrad per second). Graft-polymerization mechanisms were discussed on the basis of grafting rates, surface tensions, atomic ratios of surface by XPS, and SEM images of the grafted films. Grafting rates decreased with increasing δ of monomers, and grafting rates onto LDPE were larger than those onto HDPE. Graft chain contents on surface, which were evaluated in terms of surface tensions and atomic ratios of the surface, increased with increasing δ of monomers, and graft chain contents on surface of HDPE were higher than those of LDPE. It is assumed that mutual solubility of PE and monomers, i.e., infiltration of monomers into PE during graft-polymerization influence grafting rates and graft sites in films. In case of high mutual solubility, grafting rates were large and graft sites spread from the surface into bulk. On the other hand, in case of low mutual solubility, grafting rates were small and graft sites localized on the surface of films. (author)

  12. Investigations of heavy ion tracks in polyethylene naphthalate films

    CERN Document Server

    Starosta, W; Sartowska, B; Buczkowski, M

    1999-01-01

    The heavy ion beam (with fluence 3x10 sup 8 ion/cm sup 2) from a cyclotron has been used for irradiation of thin polyethylene naphthalate (PEN) films. Latent tracks in these polymeric films have been sensitized by UV radiation and then chemically etched in NaOH solution. The etching process parameters have been controlled by the electroconductivity method. After etching, parameters of samples have been examined by SEM and bubble point methods (Coulter[reg] Porometer II instrument). Results have shown good quality of PEN track membranes with pore sizes in the range: 0.1 - 0.5 mu m. The described procedure is known for thin polyethylene terephthalate (PET) films. Taking into consideration that PEN films have got better mechanical, thermal, gas barrier as well as better chemical resistance properties in comparison with PET films, the possibility of application of such membranes is much wider.

  13. Antimicrobial compounds in polyethylene films - characterization and content measurement techniques

    International Nuclear Information System (INIS)

    Pires, Marcia; Santos, Ramon V.; Perao, Leandro; Ellwangler, Manoela W.; Nonemacher, Regina F.; Moraes, Lilian T. de; Gorski, Sandro; Staub, Simone; Petzhold, Cesar L.

    2009-01-01

    Developments have been done in the packaging market to attend the continuous changes in consumer demands and also to keep safety and shelf life of products during transportation and storage. Active packaging is the most innovative concepts in the market. It has been defined as a packaging that changes its conditions to extend shelf life. The objective of this work is the production and characterization of active polyethylene films with antimicrobial compounds. The initial results show that analytical techniques as RX fluorescence and FTIR can be used to characterize and quantify these compounds in polyethylene films. (author)

  14. Fluence behavior of polyethylene films irradiated with high energy electrons

    International Nuclear Information System (INIS)

    Pino, Eddy Segura; Silva, Leonardo G. Andrade e

    1999-01-01

    Polymers are viscoelastic materials at all temperatures, so that mechanical loads induce time dependable deformations. The recovery of these deformations, on load release, take some time and it is not always recovered completely. The main objective of this work was to analyse the creep behavior of electron irradiated polyethylene films. From the experimental results, it was sated that polyethylene creeps less with an increase on irradiation dose and also that creep recovery in this material increases with doses but it is not complete. This behavior can be attributed to the crosslinking effect witch stabilize elements of the molecular structure of the polyethylene, thus reducing their mobility and so inhibiting the creep mechanism. The partial creep recovery could be also attributed to the reticulation effect and to the polyethylene plastic behavior. Additional information on the creep behavior was obtained by fitting the experimental data with exponential functions and evaluating the mathematical parameters with a modified Kelvin-Voigt mechanical model. (author)

  15. Some investigations on the post radiation grafting of acrylamide onto polyethylene films

    International Nuclear Information System (INIS)

    Hegazy, E-S.A.; El-Dessouky, M.M.; El-Sharabasy, S.A.

    1986-01-01

    A study has been made on the post radiation grafting of aqueous acrylamide onto low density polyethylene film. It was found that the addition of 0.05 wt % Mohr's salt reduced effectively the homopolymerization of acrylamide and the grafting process was successfully achieved. The dependence of the grafting rate on the preirradiation dose and monomer concentration was found to be of 1.43 and 1.4 order, respectively. The overall activation energy for the graft polymerization was found to be 13.5 and 1.95 Kcal/mol below and above 45 0 C, respectively. Some properties of the graft co-polymer such as swelling behaviour, electrical conductivity, and reverse osmosis desalination of saline water (water flux and salt rejection), were also investigated and the possibility of its uses in the practical applications was discussed. (author)

  16. 76 FR 48122 - Polyethylene Terephthalate Film, Sheet, and Strip From Brazil: Preliminary Results of Antidumping...

    Science.gov (United States)

    2011-08-08

    ... on polyethylene terephthalate film, sheet, and strip (PET film) from Brazil. This administrative..., 2011. FOR FURTHER INFORMATION CONTACT: Deborah Scott or Robert James, AD/CVD Operations, Office 7... antidumping duty order on PET film from Brazil. See Polyethylene Terephthalate Film, Sheet, and Strip From...

  17. 78 FR 35245 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Final...

    Science.gov (United States)

    2013-06-12

    ... polyethylene terephthalate film, sheet, and strip (``PET film'') from the People's Republic of China (``PRC... Film, Sheet, and Strip From the People's Republic of China: Final Results of Antidumping Duty..., 2011. \\1\\ See Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China...

  18. Surface Modification of Polyethylene Films using Atmospheric

    African Journals Online (AJOL)

    Dr A.B.Ahmed

    An atmospheric-pressure plasma jet (APPJ) is used to increase the wettability of ... contact angle between the water droplet and the polymer surface. The polymer films used in this ... W of RF power from the generator. The distance between ...

  19. Development of tailored indigenous marine consortia for the degradation of naturally weathered polyethylene films.

    Science.gov (United States)

    Syranidou, Evdokia; Karkanorachaki, Katerina; Amorotti, Filippo; Repouskou, Eftychia; Kroll, Kevin; Kolvenbach, Boris; Corvini, Philippe F-X; Fava, Fabio; Kalogerakis, Nicolas

    2017-01-01

    This study investigated the potential of bacterial-mediated polyethylene (PE) degradation in a two-phase microcosm experiment. During phase I, naturally weathered PE films were incubated for 6 months with the indigenous marine community alone as well as bioaugmented with strains able to grow in minimal medium with linear low-density polyethylene (LLDPE) as the sole carbon source. At the end of phase I the developed biofilm was harvested and re-inoculated with naturally weathered PE films. Bacteria from both treatments were able to establish an active population on the PE surfaces as the biofilm community developed in a time dependent way. Moreover, a convergence in the composition of these communities was observed towards an efficient PE degrading microbial network, comprising of indigenous species. In acclimated communities, genera affiliated with synthetic (PE) and natural (cellulose) polymer degraders as well as hydrocarbon degrading bacteria were enriched. The acclimated consortia (indigenous and bioaugmented) reduced more efficiently the weight of PE films in comparison to non-acclimated bacteria. The SEM images revealed a dense and compact biofilm layer and signs of bio-erosion on the surface of the films. Rheological results suggest that the polymers after microbial treatment had wider molecular mass distribution and a marginally smaller average molar mass suggesting biodegradation as opposed to abiotic degradation. Modifications on the surface chemistry were observed throughout phase II while the FTIR profiles of microbially treated films at month 6 were similar to the profiles of virgin PE. Taking into account the results, we can suggest that the tailored indigenous marine community represents an efficient consortium for degrading weathered PE plastics.

  20. Development of tailored indigenous marine consortia for the degradation of naturally weathered polyethylene films.

    Directory of Open Access Journals (Sweden)

    Evdokia Syranidou

    Full Text Available This study investigated the potential of bacterial-mediated polyethylene (PE degradation in a two-phase microcosm experiment. During phase I, naturally weathered PE films were incubated for 6 months with the indigenous marine community alone as well as bioaugmented with strains able to grow in minimal medium with linear low-density polyethylene (LLDPE as the sole carbon source. At the end of phase I the developed biofilm was harvested and re-inoculated with naturally weathered PE films. Bacteria from both treatments were able to establish an active population on the PE surfaces as the biofilm community developed in a time dependent way. Moreover, a convergence in the composition of these communities was observed towards an efficient PE degrading microbial network, comprising of indigenous species. In acclimated communities, genera affiliated with synthetic (PE and natural (cellulose polymer degraders as well as hydrocarbon degrading bacteria were enriched. The acclimated consortia (indigenous and bioaugmented reduced more efficiently the weight of PE films in comparison to non-acclimated bacteria. The SEM images revealed a dense and compact biofilm layer and signs of bio-erosion on the surface of the films. Rheological results suggest that the polymers after microbial treatment had wider molecular mass distribution and a marginally smaller average molar mass suggesting biodegradation as opposed to abiotic degradation. Modifications on the surface chemistry were observed throughout phase II while the FTIR profiles of microbially treated films at month 6 were similar to the profiles of virgin PE. Taking into account the results, we can suggest that the tailored indigenous marine community represents an efficient consortium for degrading weathered PE plastics.

  1. Influence of corona charging in cellular polyethylene film

    International Nuclear Information System (INIS)

    Ortega Brana, Gustavo; Magraner, Francisco; Quijano, Alfredo; Llovera Segovia, Pedro

    2011-01-01

    Cellular polymers have recently attracted attention for their property of exhibiting a piezoelectric constant when they are electrically charged. The electrostatic charge generated in the voids by the internal discharges creates and internal macrodipole which is responsible for the piezoelectric effect. Charging by corona discharge is the most used method for cellular polymers. Many works has been published on polypropylene and polyethylene films mainly focused on the required expansion process or on the results obtained for raw cellular materials electrically activated. Our work is based on commercial polyethylene cellular films which have been physically characterized and electrically activated. The effect of thermal treatment, physical uniaxial or biaxial stretching and corona charging was investigated. The new method of corona charging improved the piezoelectric constant under other activation conditions.

  2. Influence of corona charging in cellular polyethylene film

    Energy Technology Data Exchange (ETDEWEB)

    Ortega Brana, Gustavo; Magraner, Francisco; Quijano, Alfredo [Instituto Tecnologico de la Energia (ITE), Av. Juan de la Cierva 24, Parque Tecnologico de Valencia, 46980 Paterna-Valencia (Spain); Llovera Segovia, Pedro, E-mail: gustavo.ortega@ite.es [Instituto de TecnologIa Electrica - Universitat Politecnica de Valencia, Camino de Vera s/n 46022-Valencia (Spain)

    2011-06-23

    Cellular polymers have recently attracted attention for their property of exhibiting a piezoelectric constant when they are electrically charged. The electrostatic charge generated in the voids by the internal discharges creates and internal macrodipole which is responsible for the piezoelectric effect. Charging by corona discharge is the most used method for cellular polymers. Many works has been published on polypropylene and polyethylene films mainly focused on the required expansion process or on the results obtained for raw cellular materials electrically activated. Our work is based on commercial polyethylene cellular films which have been physically characterized and electrically activated. The effect of thermal treatment, physical uniaxial or biaxial stretching and corona charging was investigated. The new method of corona charging improved the piezoelectric constant under other activation conditions.

  3. 76 FR 76941 - Polyethylene Terephthalate Film, Sheet, and Strip From Taiwan: Final Results of Antidumping Duty...

    Science.gov (United States)

    2011-12-09

    ... on polyethylene terephthalate film, sheet and strip (PET Film) from Taiwan. The period of review (POR... Halle, AD/CVD Operations, Office 6, Import Administration, International Trade Administration, U.S... Results in the Administrative Review on Polyethylene Terephthalate Film, Sheet and Strip from Taiwan (PET...

  4. 78 FR 79400 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Initiation...

    Science.gov (United States)

    2013-12-30

    ... order on polyethylene terephthalate film, sheet, and strip (``PET film'') from the People's Republic of... INFORMATION CONTACT: Jonathan Hill, AD/CVD Operations, Office IV, Enforcement & Compliance, International... Operations, Office IV ``Initiation of Antidumping New Shipper Review of Polyethylene Terephthalate Film...

  5. Electron beam induced modification of poly(ethylene terephthalate) films

    International Nuclear Information System (INIS)

    Vasiljeva, I.V.; Mjakin, S.V.; Makarov, A.V.; Krasovsky, A.N.; Varlamov, A.V.

    2006-01-01

    Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy)

  6. Electron beam induced modification of poly(ethylene terephthalate) films

    Energy Technology Data Exchange (ETDEWEB)

    Vasiljeva, I.V. [Technology Center RADIANT, 10, Kurchatova Str., 194223 St. Petersburg (Russian Federation)]. E-mail: radiant@skylink.spb.ru; Mjakin, S.V. [Technology Center RADIANT, 10, Kurchatova Str., 194223 St. Petersburg (Russian Federation); Makarov, A.V. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation); Krasovsky, A.N. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation); Varlamov, A.V. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation)

    2006-10-15

    Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy)

  7. Spatial trends, sources, and air-water exchange of organochlorine pesticides in the Great Lakes basin using low density polyethylene passive samplers.

    Science.gov (United States)

    Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

    2014-08-19

    Polyethylene passive samplers were deployed during summer and fall of 2011 in the lower Great Lakes to assess the spatial distribution and sources of gaseous and freely dissolved organochlorine pesticides (OCPs) and their air-water exchange. Average gaseous OCP concentrations ranged from nondetect to 133 pg/m(3). Gaseous concentrations of hexachlorobenzene, dieldrin, and chlordanes were significantly greater (Mann-Whitney test, p < 0.05) at Lake Erie than Lake Ontario. A multiple linear regression implied that both cropland and urban areas within 50 and 10 km buffer zones, respectively, were critical parameters to explain the total variability in atmospheric concentrations. Freely dissolved OCP concentrations (nondetect to 114 pg/L) were lower than previously reported. Aqueous half-lives generally ranged from 1.7 to 6.7 years. Nonetheless, concentrations of p,p'-DDE and chlordanes were higher than New York State Ambient Water Quality Standards for the protection of human health from the consumption of fish. Spatial distributions of freely dissolved OCPs in both lakes were influenced by loadings from areas of concern and the water circulation patterns. Flux calculations indicated net deposition of γ-hexachlorocyclohexane, heptachlor-epoxide, and α- and β-endosulfan (-0.02 to -33 ng/m(2)/day) and net volatilization of heptachlor, aldrin, trans-chlordane, and trans-nonachlor (0.0 to 9.0 ng/m(2)/day) in most samples.

  8. A hierarchical classification approach for recognition of low-density (LDPE) and high-density polyethylene (HDPE) in mixed plastic waste based on short-wave infrared (SWIR) hyperspectral imaging

    Science.gov (United States)

    Bonifazi, Giuseppe; Capobianco, Giuseppe; Serranti, Silvia

    2018-06-01

    The aim of this work was to recognize different polymer flakes from mixed plastic waste through an innovative hierarchical classification strategy based on hyperspectral imaging, with particular reference to low density polyethylene (LDPE) and high-density polyethylene (HDPE). A plastic waste composition assessment, including also LDPE and HDPE identification, may help to define optimal recycling strategies for product quality control. Correct handling of plastic waste is essential for its further "sustainable" recovery, maximizing the sorting performance in particular for plastics with similar characteristics as LDPE and HDPE. Five different plastic waste samples were chosen for the investigation: polypropylene (PP), LDPE, HDPE, polystyrene (PS) and polyvinyl chloride (PVC). A calibration dataset was realized utilizing the corresponding virgin polymers. Hyperspectral imaging in the short-wave infrared range (1000-2500 nm) was thus applied to evaluate the different plastic spectral attributes finalized to perform their recognition/classification. After exploring polymer spectral differences by principal component analysis (PCA), a hierarchical partial least squares discriminant analysis (PLS-DA) model was built allowing the five different polymers to be recognized. The proposed methodology, based on hierarchical classification, is very powerful and fast, allowing to recognize the five different polymers in a single step.

  9. Adhesion of evaporated titanium films to ion-bombarded polyethylene

    International Nuclear Information System (INIS)

    Bodoe, P.; Sundgren, J.

    1986-01-01

    Ti films were deposited onto high-density polyethylene (HDPE) samples by electron-beam evaporation. Prior to film deposition the samples were in situ pretreated by Ar ion bombardment using a sputter ion gun. The adhesion of the films, determined as the pull strength required for film failure, was measured as a function of ion dose. HDPE substrates processed at two different temperatures were examined. The adhesion of the Ti films to HDPE samples processed at roughly-equal150 0 C increased with the ion dose to a steady-state value corresponding to the cohesive strength of the HDPE substrate. The adhesion to the samples processed at roughly-equal200 0 C increased to a maximum and then decreased for further ion bombardment to a level of the same order as that for films deposited onto as-prepared samples. The effects of the ion bombardment upon the HDPE surface chemistry were examined by means of x-ray photoelectron spectroscopy (XPS). The ion bombardment resulted in dehydrogenation and cross linking of the surface region and for prolonged ion bombardment, a graphitelike surface was obtained. The film/substrate interface as well as the initial Ti film growth were examined by XPS analysis. A chemical interaction which resulted in Ti--C bonds was observed at the interface. The Ti film growth followed a pronounced three-dimensional growth mode on as-prepared surfaces whereas the ion bombardment resulted in a change toward a more two-dimensional growth mode. The difference in adhesion behavior for the two types of HDPE substrates was found to be due to a difference in the amounts of low molecular weight products present within the substrates

  10. Radiation effects on residual voltage of polyethylene films

    International Nuclear Information System (INIS)

    Kyokane, Jun; Park, Dae-Hee; Yoshino, Katsumi.

    1986-01-01

    It has recently been pointed out that diagnosis of deterioration in insulating materials for electric cables used in nuclear power plants and outer space (communications satellite in particular) can be effectively performed based on measurements of residual voltage. In the present study, polyethylene films are irradiated with γ-rays or electron beam to examine the changes in residual voltage characteristics. Irradiation of electron beam and γ-rays are carried out to a dose of 0 - 90 Mrad and 0 - 100 Mrad, respectively. Measurements are made of the dependence of residual voltage on applied voltage, electron beam and γ-ray irradiation, annealing temperature and annealing time. Results show that carriers, which are once trapped after being released from the electrode, move within the material after the opening of the circuit to produce resiual voltage. The residual voltage increases with increasing dose of electron beam or γ-ray and levels off at high dose. Residual voltage is increased about several times by either electron beam or γ-rays, but electron beam tends to cause greater residual voltage than γ-ray. Polyethylene films irradiated with electron beam can recover upon annealing. It is concluded from observations made that residual voltage has close relations with defects in molecular structures caused by radiations, particularly the breaking of backbone chains and alteration in superstructures. (Nogami, K.)

  11. Experimental Results of Thin-Film Photovoltaic Cells in a Low Density LEO Plasma Environment: Ground Tests

    Science.gov (United States)

    Galofaro, Joel T.; Vayner, Boris V.

    2006-01-01

    Plasma ground testing results, conducted at the Glenn Research Center (GRC) National Plasma Interaction (N-PI) Facility, are presented for a number of thin-film photovoltaic cells. The cells represent a mix of promising new technologies identified by the Air Force Research Laboratory (AFRL) under the CYGNUS Space Science Technology Experiment (SSTE-4) Program. The current ground tests are aimed at characterizing the performance and survivability of thin film technologies in the harsh low earth orbital space environment where they will be flown. Measurements of parasitic current loss, charging/dielectric breakdown of cover-slide coatings and arcing threshold tests are performed for each individual cell. These measurements are followed by a series of experiments designed to test for catastrophic arc failure mechanisms. A special type of power supply, called a solar array simulator (SAS) with adjustable voltage and current limits on the supply s output, is employed to bias two adjacent cells at a predetermined voltage and current. The bias voltage is incrementally ramped up until a sustained arc results. Sustained arcs are precursors to catastrophic arc failure where the arc current rises to a maximum value for long timescales often ranging between 30 to 100 sec times. Normal arcs by comparison, are short lived events with a timescale between 10 to 30 sec. Sustained arcs lead to pyrolization with extreme cell damage and have been shown to cause the loss of entire array strings in solar arrays. The collected data will be used to evaluate the suitability of thin-film photovoltaic technologies for future space operations.

  12. 78 FR 77649 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates; Preliminary...

    Science.gov (United States)

    2013-12-24

    ... Film, Sheet, and Strip From the United Arab Emirates; Preliminary Results of Antidumping Duty... film, sheet, and strip (PET Film) from the United Arab Emirates (UAE). The period of review (POR) is... Administrative Review: Polyethylene Terephthalate Film, Sheet, and Strip from the United Arab Emirates...

  13. Nanocomposites Based on Polyethylene and Nanocrystalline Silicon Films

    Directory of Open Access Journals (Sweden)

    Olkhov Anatoliy Aleksandrovich

    2014-12-01

    Full Text Available High-strength polyethylene films containing 0.5-1.0 wt. % of nanocrystalline silicon (nc-Si were synthesized. Samples of nc-Si with an average core diameter of 7-10 nm were produced by plasmochemical method and by laser-induced decomposition of monosilane. Spectral studies revealed almost complete (up to ~95 % absorption of UV radiation in 200- 400 nm spectral region by 85 micron thick film if the nc-Si content approaches to 1.0 wt. %. The density function of particle size in the starting powders and polymer films containing immobilized silicon nanocrystallites were obtained using the modeling a complete profile of X-ray diffraction patterns, assuming spherical grains and the lognormal distribution. The results of X-ray analysis shown that the crystallite size distribution function remains almost unchanged and the crystallinity of the original polymer increases to about 10 % with the implantation of the initial nc-Si samples in the polymer matrix.

  14. Permeability coefficient of proton irradiated polyethylene terephatalate thin films

    International Nuclear Information System (INIS)

    Bassani, L.C.; Santos, W.M.S.; Marechal, B.

    1983-01-01

    The principle of operation of an apparatus developed to study gas permation through thin films is described and the measurement method is discussed. Use is made of diffusion theory to obtain a expression for the permeability coefficient as a function of the rate of increase of the pressure in the receiving volume. The Gibbs function for permeation of Helium through Polyethylene Terephtalate (P.E.T.) is determined. The permeability coefficient of Helium is found to increase significantly with the range of the implanted protons although the incident charge has been kept constant. The hypothesis of structural modifications of the proton implanted P.E.T. seems to be confirmed by small angles X-rays scattering experiments on the irradiated samples. (Author) [pt

  15. Deformation of confined poly(ethylene oxide) in multilayer films.

    Science.gov (United States)

    Lai, Chuan-Yar; Hiltner, Anne; Baer, Eric; Korley, LaShanda T J

    2012-04-01

    The effect of confinement on the deformation behavior of poly(ethylene oxide) (PEO) was studied using melt processed coextruded poly(ethylene-co-acrylic acid) (EAA) and PEO multilayer films with varying PEO layer thicknesses from 3600 to 25 nm. The deformation mechanism was found to shift as layer thickness was decreased between 510 and 125 nm, from typical axial alignment of the crystalline fraction, as seen in bulk materials, to nonuniform micronecking mechanisms found in solution-grown single crystals. This change was evaluated via tensile testing, wide-angle X-ray diffraction (WAXD), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). With the commercially relevant method of melt coextrusion, we were able to overcome the limitations to the testing of solution-grown single crystals, and the artifacts that occur from their handling, and bridged the gap in knowledge between thick bulk materials and thin single crystals.

  16. Low Density Supersonic Decelerators

    Data.gov (United States)

    National Aeronautics and Space Administration — The Low-Density Supersonic Decelerator project will demonstrate the use of inflatable structures and advanced parachutes that operate at supersonic speeds to more...

  17. Evaluation of the physico-chemical properties of nanocomposites of low density linear polyethylene and organophilic montmorillonite obtained by fusion; Avaliacao das propriedades fisico-quimicas de nanocompositos de polietileno linear de baixa densidade e montmorilonita organofilica obtidos por fusao

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, Aline; Sandrin, Bianca M.; Pezzin, A.P.T., E-mail: anapezzin@yahoo.com.br [Universidade da Regiao de Joinville (UNIVILLE), SC (Brazil); Meier, Marcia M. [Universidade do Estado de Santa Catarina (UESC), Joinville, SC (Brazil). Departamento de Quimica; Balzer, Palova S. [Centro Universitario Unisociesc, Joinville, SC (Brazil). Departamento de Engenharia Mecanica; Tavares, Maria I.B. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Laboratorio de Solucoes em Ralaxometria

    2016-07-01

    In this project they were produced and characterized nanocomposite organoclay applied to linear low density polyethylene in order to improve their physicochemical properties. Samples were produced by means of extrusion and injection process, varying proportions of nanoclay (2; 2.5; 3.0 and 3.5%) in LLDPE. Samples nanocomposites were characterized by TGA, DSC and Flammability test (UL-94). The TGA analysis showed that adding nanoclay increased thermal stability, especially for LLDPE / OMMT2,0 sample increased thermal stability at 4.4%. By DSC it was found that samples with nanoclay incorporation did not affect the Tm of LLDPE, though the increase of nanoclay raised the degree of crystallinity of the samples 52.7% in LLDPE / 2.5 OMMT sample. The flammability results show that the sample LLDPE / OMMT 2.0 showed a decrease of 37.77% in the flame propagation velocity. The NMR showed that the samples up LLDPE / 2.5 OM has an exfoliated nanocomposite formation. (author)

  18. Structural, luminescent and thermal properties of blue SrAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} phosphor filled low-density polyethylene composites

    Energy Technology Data Exchange (ETDEWEB)

    Bem, D.B. [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Luyt, A.S. [Department of Chemistry, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Dejene, F.B., E-mail: dejenebf@qwa.ufs.ac.z [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Botha, J.R. [Department of Physics, Nelson Mandela Metropolitan University, P.O. Box 70000, Port Elizabeth 6031 (South Africa); Swart, H.C. [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein 9300 (South Africa)

    2009-12-01

    The performance of nanophase luminophors is usually compromised by environmentally induced degradation. In this study, composites of low density polyethylene (LDPE) with various concentrations of the blue-emitting europium and dysprosium co-doped strontium aluminate (SrAl{sub 2}O{sub 4}:Eu{sup 2+},Dy{sup 3+}) phosphor were investigated. The blue long-lasting phosphorescence of the composites was observed in the dark after removal of the excitation light. X-ray diffraction analysis revealed the presence of the SrAl{sub 2}O{sub 4} phase in the composites. PL spectra of the composites have two sets of peaks, major broad bands peaking at about 4855 A and minor ones at wavelengths between 4115 and 4175 A, attributed to the 4f-5d transition of Eu{sup 2+}. DSC and TGA results show that the introduction of the phosphor in LDPE matrix caused a slight reduction in the crystallinity of LDPE but a significant increase in the stability of the composites.

  19. A study of the barrier properties of polyethylene coated with a nanocellulose/magnetite composite film

    Directory of Open Access Journals (Sweden)

    Đorđević Nenad

    2016-01-01

    Full Text Available The morphological, thermal and barrier properties of low-density polyethylene/polycaprolactone-modified nanocellulose hybrid materials were investigated in this paper. Nanonocelulose/magnetite (NC-Fe3O4 nanocomposite and maleic acid functionalized NC/magnetite (NCMA-Fe3O4 nanocomposite were prepared and used as filler at various concentrations (5, 10 and 15 wt. % in polycaprolactone (PCL layer. PE was coated with PCL/NC/magnetite layer. The addition of the filler did not unfavorably affect the inherent properties of the polymer, especially its barrier properties. Oxygen permeation measurements show that the oxygen barrier properties of magnetite enriched PCL film were improved due to chemical activity of added material. The highest level of barrier capacity was observed for PE samples coated with PCL based composite with NCMA-Fe3O4 micro/-nanofiller, which implies the significant contribution of nanocellulose surface modification with maleic anhydride residue to improved barrier properties. [Projekat Ministarstva nauke Republike Srbije, br. III45019 i br. OI172013

  20. 78 FR 9670 - Polyethylene Terephthalate Film, Sheet, and Strip From India: Final Results of Administrative...

    Science.gov (United States)

    2013-02-11

    ... administrative review of the antidumping duty order on polyethylene terephthalate film (PET Film) from India.\\1.... (Polyplex), and SRF Limited (SRF), producers and exporters of PET Film from India. Based on the results of... FURTHER INFORMATION CONTACT: Elfi Blum or Toni Page, AD/CVD Operations, Office 6, Import Administration...

  1. 76 FR 9745 - Polyethylene Terephthalate Film, Sheet, and Strip From Taiwan: Final Results of Antidumping Duty...

    Science.gov (United States)

    2011-02-22

    ... review of the antidumping duty order on polyethylene terephthalate film (PET Film) from Taiwan. See... Jun Jack Zhao, AD/CVD Operations, Office 6, Import Administration, International Trade Administration... products produced by Nan Ya, are not covered by the scope of the antidumping order on PET Film from Taiwan...

  2. 78 FR 48651 - Polyethylene Terephthalate Film, Sheet, and Strip From Taiwan; Preliminary Results of Antidumping...

    Science.gov (United States)

    2013-08-09

    ... duty order on polyethylene terephthalate film, sheet, and strip (PET Film) from Taiwan. The period of.... (SMTC) (collectively, Shinkong), producer and exporter of PET Film from Taiwan. The Department...: Milton Koch, AD/CVD Operations, Office 6, Import Administration, International Trade Administration, U.S...

  3. 78 FR 67113 - Polyethylene Terephthalate Film, Sheet and Strip From India and Taiwan: Preliminary Results of...

    Science.gov (United States)

    2013-11-08

    ... antidumping duty orders on Polyethylene Terephthalate Film, Sheet and Strip (``PET Film'') from India and... Operations, Office VII, Enforcement and Compliance, International Trade Administration, U.S. Department of...) 482-2371, respectively. SUPPLEMENTARY INFORMATION: Background The antidumping duty orders on PET Film...

  4. 78 FR 50029 - Polyethylene Terephthalate Film, Sheet and Strip From Brazil: Preliminary Results of Antidumping...

    Science.gov (United States)

    2013-08-16

    ... the antidumping duty order on polyethylene terephthalate film, sheet and strip (PET film) from Brazil... any reviewable entries, shipments or sales of subject PET film by Terphane during the POR, we are.... FOR FURTHER INFORMATION CONTACT: Tyler Weinhold or Robert James, AD/CVD Operations, Office 7, Import...

  5. 76 FR 76948 - Polyethylene Terephthalate Film, Sheet, and Strip From India: Final Results of Countervailing...

    Science.gov (United States)

    2011-12-09

    ... review of polyethylene terephthalate film, sheet and strip (PET Film) from India for Ester Industries Ltd... export of PET Film from India. Also, based on our analysis of Ester's comments, we made certain revisions..., Office 6, Import Administration, International Trade Administration, U.S. Department of Commerce, 14th...

  6. 78 FR 42105 - Polyethylene Terephthalate Film, Sheet, and Strip From India and Taiwan; Notice of Commission...

    Science.gov (United States)

    2013-07-15

    ... countervailing duty order on polyethylene terephthalate film, sheet, and strip (``PET'' film) from India and the antidumping duty orders on PET film from India and Taiwan would be likely to lead to continuation or...-205-3169), Office of Investigations, U.S. International Trade Commission, 500 E Street SW., Washington...

  7. Influência da embalagem de polietileno de baixa densidade e da temperatura na conservação do repolho minimamente processado Effects of low density polyethylene packaging and temperature in the conservation of fresh-cut cabbage

    Directory of Open Access Journals (Sweden)

    Maria M. Rinaldi

    2004-08-01

    Full Text Available Neste trabalho, foi estudado o efeito da embalagem de polietileno de baixa densidade e da temperatura de armazenagem na conservação de repolho minimamente processado. Os repolhos, previamente resfriados à temperatura de 10 ºC, foram submetidos à seleção, lavagem, corte em quatro partes com a retirada do talo central, sanitização, corte em tiras, enxágüe, centrifugação, pesagem e acondicionamento em embalagens plásticas de polietileno de baixa densidade (70 µm e armazenados em câmaras frias nas temperaturas de 1 e 10 ºC por 20 dias. Avaliaram-se dióxido de carbono, oxigênio e etileno na atmosfera interna da embalagem, bem como pH, acidez titulável, sólidos solúveis totais, vitamina C, perda de massa fresca e relação sólidos solúveis totais/acidez no repolho minimamente processado. O delineamento estatístico utilizado foi o inteiramente casualizado, com três repetições. Os parâmetros de análise, com exceção da vitamina C, perda de massa fresca e etileno, apresentaram variação significativa entre as temperaturas e dias de armazenamento. O repolho armazenado na temperatura de 1 ºC apresentou vida de prateleira ao redor de 15 dias, significativamente maior que a 10 ºC. Nesta última, no 8º dia de armazenamento, o produto encontrava-se totalmente deteriorado, sem condições de comercialização e consumo.This research studied the effect of low density polyethylene packaging and storage temperature on the preservation of fresh-cut (minimally processed cabbage. The cabbages, previously cooled to a temperature of 10 ºC, were selected, washed, cut in four parts (with the central stalk removed, sanitized, cut in strips, rinsed, put in the centrifuge, weighed and stored in plastic packaging of low density polyethylene (70 µm, and then stored in cold chambers at temperatures of 1 and 10 ºC for 20 days. The following aspects were evaluated: carbon dioxide, oxygen and ethylene in the internal atmosphere of the package

  8. Electron-beam-induced conduction in polyethylene terephthalate films

    Energy Technology Data Exchange (ETDEWEB)

    Beckley, L M; Lewis, T J; Taylor, D M [University Coll. of North Wales, Bangor (UK). School of Electronic Engineering Science

    1976-06-21

    Measurements are reported of electron-beam-induced conduction in thin polyethylene terephthalate (PET) films for electron energies up to 10 keV. The ratio of induced dielectric current to incident beam current (the gain) is orders of magnitude less than unity over practically the whole range of beam penetration. This result is quite unlike that normally found for inorganic dielectrics where the gain will exceed unity and reach a maximum at or near full penetration. In spite of the very different gain characteristics it is shown that the model recently proposed by Nunes de Oliviera and Gross (J. App. Phys.; 46:3132 (1975)), and by Aris et al (IEE Conf. Publ. No.129.; 267 (1975) and J. Phys. C. Solid State Phys.; 9:797 (1976)) and applied to mica and tantalum oxide respectively is also applicable to PET. Use is made of the known carrier mobility and lifetime data for this polymer and it is shown that very large space-charge distortions of the field can be produced by the beam which may well account for the frequent sample failure experienced during the experiments. The work supports suggestions by earlier workers that the current in unirradiated PET is electrode limited and predicts the maximum (space-charge limited) current likely to occur in this polymer.

  9. Biodegradation evaluation of recycled polyethylene doped with Moringa oleifera oil; Avaliacao da biodegradacao de filmes de polietileno reciclado dopados com oleo de Moringa oleifera

    Energy Technology Data Exchange (ETDEWEB)

    Bicalho, Luciana A.; Novack, Katia M.; Melo, Tania M.S., E-mail: knovack@iceb.ufop.br [Dept. de Quimica (DEQUI) - Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG (Brazil)

    2011-07-01

    Chemical modifications and use of additives are some of the mainly ways to obtain polymer materials with especial properties. Vegetable oils incorporated to polymers preserve their structure while make possible a reduction of degradation rate. This work proposed the use of polyethylene, one of the most common polymer commodities, because of its low cost and wide application. In this project it was verified the possibility of making polymer materials with properties of a natural product through the incorporation of Moringa oleifera oil to recycled low density polyethylene (LDPEr) in different proportions. The films were buried for different times and their degradation was evaluated.) Samples were characterized by DSC, TGA and XRD. It was observed that samples doped with Moringa oil showed lower degradation time. (author)

  10. 76 FR 30910 - Polyethylene Terephthalate Film, Sheet, and Strip From India: Final Results of Countervailing...

    Science.gov (United States)

    2011-05-27

    ... shipper review of polyethylene terephthalate film, sheet and strip (PET Film) from India for SRF Limited... Operations, Office 6, Import Administration, International Trade Administration, U.S. Department of Commerce..., International Trade Compliance Analyst, AD/CVD Operations, Office 6: New Shipper Reviews of the Antidumping Duty...

  11. 76 FR 30908 - Polyethylene Terephthalate Film, Sheet, and Strip From India: Final Results of Antidumping Duty...

    Science.gov (United States)

    2011-05-27

    ... polyethylene terephthalate film, sheet and strip (PET Film) from India for SRF Limited (SRF), covering the... Page or Elfi Blum, AD/CVD Operations, Office 6, Import Administration, International Trade... Interested Parties From Elfi Blum, International Trade Compliance Analyst, AD/CVD Operations, Office 6: New...

  12. 75 FR 6634 - Polyethylene Terephthalate Film, Sheet, and Strip from India: Final Results of Countervailing...

    Science.gov (United States)

    2010-02-10

    ... of the countervailing duty order on polyethylene terephthalate film, sheet, and strip (PET film) from....'' EFFECTIVE DATE: February 10, 2010. FOR FURTHER INFORMATION CONTACT: Elfi Blum, AD/CVD Operations, Office 6... Assistant Secretary for Import Administration, from Barbara E. Tillman, Director, AD/CVD Operations, Office...

  13. Detection of viral antigens by solid phase radioimmunoassay on polyethylene film

    Energy Technology Data Exchange (ETDEWEB)

    Prokudina, E N; Semenova, N P; Zhdanov, V M

    1986-04-01

    Polyethylene film, without any pretreatment, may serve as a solid phase (SP) for RIA. Viral antigens (HBsAg, and influenza virus) are detected by SP-RIA on the film with a sensitivity of about 2-3 ng/ml or 40-60 pg/assay. The use of polyethylene film allows one to record RIA autographically. The use of micro amounts of reagents and specimens tested is an added advantage. No special equipment is necessary, the method is inexpensive, easy to perform and may be used for mass screening. (Auth.). 7 refs.; 4 figs.

  14. Effect of ultraviolet radiation in the photo-oxidation of High Density Polyethylene and Biodegradable Polyethylene films

    International Nuclear Information System (INIS)

    Martínez-Romo, A; Mota, R González; Bernal, J J Soto; Candelas, I Rosales; Reyes, C Frausto

    2015-01-01

    One of the most widely used plastics in the world is the High density polyethylene (HDPE), it is a stable material due to its carbon-carbon bonds, causing their slow degradation; which is why we are looking for alternative ways to accelerate the degradation process of this polymer. An alternative is the addition of oxidized groups in its molecular structure, which results in the development of polymers susceptible to biodegradation (PE-BIO). In this paper, HDPE and PE-BIO films were exposed to UV-B radiation (320-280 nm) at different exposure times, 0-60 days. The effects of UV radiation in samples of HDPE and PE-BIO were characterized using infrared spectroscopy with attenuated total reflectance (ATR). The results show that the exposed materials undergo changes in their molecular structure, due to the infrared bands formed which corresponds to the photo-oxidation of HDPE and PE films when submitted to UV-B radiation

  15. Experimental study on tensile bifurcation of nanoscale Cu film bonded to polyethylene terephthalate substrate

    International Nuclear Information System (INIS)

    Men, Yutao; Wang, Shibin; Jia, Haikun; Wu, Zhiliang; Li, Linan; Zhang, Chunqiu

    2013-01-01

    Cu films are widely used in flexible electronic products. Tensile mechanical properties of the film determine product performance. In this paper, tensile experiments of sputtered Cu films on a polyethylene terephthalate (PET) substrate were carried out under an optical microscope. In the experiments, three changes took place under tension: uniform deformation, microcrack initiation and propagation, and microcrack saturation. The elastic modulus of the Cu film is 120 GPa and is independent of film thickness since the film is formed to be continuous in the nanoscale range. Film thickness is an important parameter to decide the tensile properties. The critical fracture strain, the interfacial bonding strength, and the crack spacing after saturation are related to film thickness. The critical strain and the interfacial bonding strength of the nanoscale Cu film tend to ascend then to descend as film thickness increases. The microcrack spacing is in direct proportion to film thickness after the microcrack saturates. The optimum thickness of the sputtered Cu films on the PET substrate is about 500 nm. - Highlights: • The elastic modulus of the Cu films is 120 GPa and does not change with thickness. • The optimal thickness of the Cu films is about 500 nm. • The critical strain tends to ascend then to descend as film thickness increases. • The interfacial strength changes in accordance with the critical strain. • Microcrack spacing is proportional to film thickness after the microcrack saturates

  16. 76 FR 57715 - Polyethylene Terephthalate Film, Sheet, and Strip From the Republic of Korea: Revocation of...

    Science.gov (United States)

    2011-09-16

    ..., and strip from the Republic of Korea would not be likely to lead to continuation or recurrence of... of Sales at Less Than Fair Value: Polyethylene Terephthalate Film, Sheet, and Strip From the Republic..., the Department determined that revocation of the antidumping duty order would be likely to lead to the...

  17. Recovery of electrical resistance in copper films on polyethylene terephthalate subjected to a tensile strain

    International Nuclear Information System (INIS)

    Glushko, O.; Marx, V.M.; Kirchlechner, C.; Zizak, I.; Cordill, M.J.

    2014-01-01

    Substantial recovery (decrease) of electrical resistance during and after unloading is demonstrated for copper films on polyethylene terephthalate substrates subjected to a tensile strain with different peak values. Particularly, the films strained to 5% exhibit full resistance recovery after unloading despite clearly visible plastic deformation of the film. The recovery of electrical resistance in connection with the mechanical behavior of film/substrate couple is discussed with the help of in situ scanning electron microscopy and X-ray diffraction analysis. - Highlights: • Tensile tests on 200 nm Cu films on PET substrate are performed. • Electrical resistance is recorded in-situ during loading and unloading. • Significant recovery (decrease) of resistance is observed during and after unloading. • Films strained to 5% demonstrate full resistance recovery. • Viscoelastic relaxation of PET is responsible for recovery of Cu film resistance

  18. High PEC conversion efficiencies from CuSe film electrodes modified with metalloporphyrin/polyethylene matrices

    International Nuclear Information System (INIS)

    Zyoud, Ahed; Al-Kerm, Rola S.; Al-Kerm, Rana S.; Waseem, Mansur; Mohammed, H.S. Helal; Park, DaeHoon; Campet, Guy; Sabli, Nordin; Hilal, Hikmat S.

    2015-01-01

    Enhancement of hole-transfer across CuSe electrode/liquid junction can be facilitated by coating with metalloporphyrin complexes embedded inside polyethylene matrices. - Highlights: • CuSe films were electrochemically deposited onto FTO/Glass • Annealing CuSe film electrodes enhanced PEC characteristics • PEC characteristics were further enhanced by metalloporphyrin/polyethylene matrices, yielding ∼15% efficiency • Matrix behavior as charge transfer mediator enhanced electrode conversion efficiency and stability - Abstract: Electrodeposited CuSe film electrodes have been prepared onto FTO/glass by a facile method based on earlier methods described for other systems. The films were characterized, modified by annealing and further characterized. The films were then modified by coating with tetra(-4-pyridyl) pophyrinato-manganese (MnTPyP) complexes embedded inside commercial polyethylene (PE) matrices. The effects of modifications on different film properties, such as X-ray diffraction (XRD) patterns, surface morphology, photoluminescence (PL) spectra and electronic absorption spectra were investigated. Compared with other thin film electrode systems, very high photoelectrochemical (PEC) conversion efficiency values have been observed here. Pre-annealing the CuSe films at 150°C for 2 h, followed by attaching the MnTPyP/PE matrices remarkably enhanced their PEC characteristics. The conversion efficiency was significantly enhanced, from less than 1.0% to more than 15%. Fill factor (FF) was also enhanced from ∼30% to ∼80%. Values of open-circuit potential (V OC ) and short-circuit current (J SC ) were significantly enhanced. While annealing affects uniformity, particle inter-connection and surface texture of the CuSe films, the MnTPyP complex species behaves as an additional charge-transfer mediator across the film/electrolyte junction. Optimization of PEC characteristics, using different deposition times, different annealing temperatures, different

  19. Heat shrink ability of electron-beam-modified thermoplastic elastomeric films from blends of ethylene-vinylacetate copolymer and polyethylene

    International Nuclear Information System (INIS)

    Chattopadhyay, S.; Chaki, T.K.; Bhowmick, Anil K.

    2000-01-01

    The heat shrink ability of electron-beam-irradiated thermoplastic elastomeric films from blends of ethylene-vinylacetate copolymer (EVA) and low-density polyethylene (LDPE) has been investigated in this paper. The effects of temperature, time and extent of stretching and shrinkage temperature and time have been reported. Based on the above data, the optimized conditions in terms of high heat shrinkage and low amnesia rating have been evaluated. Influence of radiation doses (0-500 kGy), multifunctional sensitizer levels (ditri methylol propane tetraacrylate, DTMPTA), and blend proportions on heat shrink ability has been explained with the help of gel fraction and X-ray data. With the increase in radiation dose, gel fraction increases, which in turn gives rise to low values of heat shrinkage and amnesia rating. At a constant radiation dose and blend ratio, percent heat shrinkage is found to decrease with increase in DTMPTA level. Gel content increases with the increase in EVA content of the blend at a constant radiation dose and monomer level, giving rise to decrease in heat shrink ability. Heat shrinkage increases with the increase in percent crystallinity, although the amnesia rating follows the reverse trend.

  20. Heat shrink ability of electron-beam-modified thermoplastic elastomeric films from blends of ethylene-vinylacetate copolymer and polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, S.; Chaki, T.K.; Bhowmick, Anil K. E-mail: anilkb@rtc.iitkgp.ernet.in

    2000-11-01

    The heat shrink ability of electron-beam-irradiated thermoplastic elastomeric films from blends of ethylene-vinylacetate copolymer (EVA) and low-density polyethylene (LDPE) has been investigated in this paper. The effects of temperature, time and extent of stretching and shrinkage temperature and time have been reported. Based on the above data, the optimized conditions in terms of high heat shrinkage and low amnesia rating have been evaluated. Influence of radiation doses (0-500 kGy), multifunctional sensitizer levels (ditri methylol propane tetraacrylate, DTMPTA), and blend proportions on heat shrink ability has been explained with the help of gel fraction and X-ray data. With the increase in radiation dose, gel fraction increases, which in turn gives rise to low values of heat shrinkage and amnesia rating. At a constant radiation dose and blend ratio, percent heat shrinkage is found to decrease with increase in DTMPTA level. Gel content increases with the increase in EVA content of the blend at a constant radiation dose and monomer level, giving rise to decrease in heat shrink ability. Heat shrinkage increases with the increase in percent crystallinity, although the amnesia rating follows the reverse trend.

  1. Preparation and Characterization of Films Extruded of Polyethylene/Chitosan Modified with Poly(lactic acid)

    Science.gov (United States)

    Quiroz-Castillo, Jesús Manuel; Rodríguez-Félix, Dora Evelia; Grijalva-Monteverde, Heriberto; Lizárraga-Laborín, Lauren Lucero; Castillo-Ortega, María Mónica; del Castillo-Castro, Teresa; Rodríguez-Félix, Francisco; Herrera-Franco, Pedro Jesús

    2014-01-01

    The use of mixtures of synthetic and natural polymers is a potential option to reduce the pollution by plastic waste. In this work, the method for the chemical modification of chitosan with poly(lactic acid) was developed; then, the preparation of films of blends of polyethylene and chitosan-poly(lactic acid) produced by an extrusion method using polyethylene-graft maleic anhydride as a compatibilizer. It was possible to obtain films with a maximum content of 20 wt% and 30 wt%, chitosan, with and without compatibilizer, respectively. Scanning electron microscope (SEM) analysis showed a homogeneous surface on all films. The addition of the compatibilizer had a significant effect on the mechanical properties of the films, such as an increase in Young’s modulus and a decrease in the elongation at break; additionally, the compatibilizer promotes thermal degradation in a single step and gives the film a slight increase in thermal resistance. These results are attributed to an improved interaction in the interface of polyethylene and chitosan-poly(lactic acid), promoted by the compatibilizer. PMID:28787928

  2. Preparation and Characterization of Films Extruded of Polyethylene/Chitosan Modified with Poly(lactic acid

    Directory of Open Access Journals (Sweden)

    Jesús Manuel Quiroz-Castillo

    2014-12-01

    Full Text Available The use of mixtures of synthetic and natural polymers is a potential option to reduce the pollution by plastic waste. In this work, the method for the chemical modification of chitosan with poly(lactic acid was developed; then, the preparation of films of blends of polyethylene and chitosan-poly(lactic acid produced by an extrusion method using polyethylene-graft maleic anhydride as a compatibilizer. It was possible to obtain films with a maximum content of 20 wt% and 30 wt%, chitosan, with and without compatibilizer, respectively. Scanning electron microscope (SEM analysis showed a homogeneous surface on all films. The addition of the compatibilizer had a significant effect on the mechanical properties of the films, such as an increase in Young’s modulus and a decrease in the elongation at break; additionally, the compatibilizer promotes thermal degradation in a single step and gives the film a slight increase in thermal resistance. These results are attributed to an improved interaction in the interface of polyethylene and chitosan-poly(lactic acid, promoted by the compatibilizer.

  3. Transparent and conductive polyethylene oxide film by the introduction of individualized single-walled carbon nanotubes.

    Science.gov (United States)

    Jung, Yong Chae; Muramatsu, Hiroyuki; Park, Ki Chul; Shimamoto, Daisuke; Kim, Jin Hee; Hayashi, Takuya; Song, Sung Moo; Kim, Yoong Ahm; Endo, Morinobu; Dresselhaus, Mildred S

    2009-12-16

    It is demonstrated that an optically transparent and electrically conductive polyethylene oxide (PEO) film is fabricated by the introduction of individualized single-walled carbon nanotubes (SWNTs). The incorporated SWNTs in the PEO film sustain their intrinsic electronic and optical properties and, in addition, the intrinsic properties of the polymer matrix are retained. The individualized SWNTs with smaller diameter provide high transmittance as well as good electrical conductivity in PEO films. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Crystallization of calcium carbonate on radiation-grafted polyethylene films

    International Nuclear Information System (INIS)

    Hou Zhengchi; Zhang Fengying; Deng Bo; Yang Haijun; Chen Shuang; Sheng Kanglong

    2006-01-01

    In biomineralization processes, nucleation and growth of inorganic crystals can be regulated by organic template molecules. This has inspired great interest in studying mimic biomineralization. In our study, growing CaCO 3 crystals on PE films functionalized through radiation-induced grafting was attempted. PE films grafted with different functional groups of different distributions and densities were used as substrates for CaCO 3 nucleation and crystal growth from Ca(HCO 3 ) 2 supersaturated solution under different environmental conditions (e.g. additives and temperature) to study the effects and mechanisms. The grafted PE films were analyzed by ATR-FTIR and AFM, and the evolution of CaCO 3 crystal formation on the grafted PE film was characterized by SEM, FTIR, and XRD. The results indicated that heterogeneous nucleation of CaCO 3 crystals was significantly facilitated by the functional groups grafted on the surface of PE films, that the morphology of CaCO 3 crystals could be controlled by distribution and density of the grafted functional groups, and that polymorphism of CaCO 3 crystal could be regulated by selection of grafting functional groups. We believe that studying the effects of chemical structures on inorganic crystallization is of great importance since radiation-induced grafting is an effective method to graft desirable functional groups onto different polymers by selected monomers, in the endeavor of developing advanced organic/inorganic composites with high performance, with a wide availability of polymers, monomers and inorganic solutions. (authors)

  5. Effect of hydroxyl bond formation on the adhesion improvement of a polyethylene copper thin film system

    International Nuclear Information System (INIS)

    Camacho, M.; Blantocas, G.; Ramos, H.

    2009-01-01

    Formation of hydroxyl bonds on the surface of a gas plasma treated high density polyethylene (HDPE) sheets significantly enhanced the adhesion strength of the polyethylene copper thin film system. Surface treatments using oxygen gas plasmas at varying plasma parameters are applied in this study to identify the most effective plasma parameters that would promote the best adhesion strength. Analysis of gas plasma adulterated HDPE sheets showed best enhancement of polyethylene copper adhesion after an oxygen gas plasma treatment for 60 minutes at 5mA discharge current. Scanning Electron Microscopy Analysis, Fourier Transform Infrared Spectroscopy and Adhesion measurements using Pull out Force Analysis were used to measure the changes in the surface chemistry and surface topology of the HDPE sheets. (author)

  6. Transient behaviors of ZnO thin films on a transparent, flexible polyethylene terephthalate substrate

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Jun [Department of Nano-Physics, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-701 (Korea, Republic of); Lee, Ho Seok [Department of Materials Science and Engineering, Korea University, 5-1 Anam-dong, Seongbuk-gu, Seoul 136-713 (Korea, Republic of); Noh, Jin-Seo, E-mail: jinseonoh@gachon.ac.kr [Department of Nano-Physics, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-701 (Korea, Republic of)

    2016-03-31

    Thickness-dependent electrical, structural, and optical properties of zinc oxide (ZnO) thin films on polyethylene terephthalate (PET) substrates have been investigated in the very thin thickness range of 20 to 120 nm. In this thickness range, the electrical resistance of ZnO film increased with an increase in film thickness. This unusual transition behavior was explained in terms of structural evolution from Zn-phase-incorporating non-crystalline ZnO to hexagonal-structured ZnO. A critical thickness for the full development of hexagonal ZnO crystal was estimated at approximately 80 nm in this study. ZnO thin films on PET substrates exhibit a high optical transmittance of > 70% and good endurance to bending cycles over the measured thickness range. The results of this study indicate that a trade-off should be sought between structural, electrical, optical, and mechanical properties for practical applications of very thin ZnO films on organic substrates. - Highlights: • Very thin ZnO films were sputter-deposited on the PET substrate. • The ZnO film resistance increases with an increase in film thickness until saturation. • Hexagonal crystal structures gradually develop with increasing film thickness. • A Zn phase appears in a 20-nm-thick ZnO film. • ZnO films show high optical transmittance of > 80% and good endurance to bending.

  7. Transient behaviors of ZnO thin films on a transparent, flexible polyethylene terephthalate substrate

    International Nuclear Information System (INIS)

    Kim, Yong Jun; Lee, Ho Seok; Noh, Jin-Seo

    2016-01-01

    Thickness-dependent electrical, structural, and optical properties of zinc oxide (ZnO) thin films on polyethylene terephthalate (PET) substrates have been investigated in the very thin thickness range of 20 to 120 nm. In this thickness range, the electrical resistance of ZnO film increased with an increase in film thickness. This unusual transition behavior was explained in terms of structural evolution from Zn-phase-incorporating non-crystalline ZnO to hexagonal-structured ZnO. A critical thickness for the full development of hexagonal ZnO crystal was estimated at approximately 80 nm in this study. ZnO thin films on PET substrates exhibit a high optical transmittance of > 70% and good endurance to bending cycles over the measured thickness range. The results of this study indicate that a trade-off should be sought between structural, electrical, optical, and mechanical properties for practical applications of very thin ZnO films on organic substrates. - Highlights: • Very thin ZnO films were sputter-deposited on the PET substrate. • The ZnO film resistance increases with an increase in film thickness until saturation. • Hexagonal crystal structures gradually develop with increasing film thickness. • A Zn phase appears in a 20-nm-thick ZnO film. • ZnO films show high optical transmittance of > 80% and good endurance to bending.

  8. Plasma-treated polyethylene film: A smart material applied for Salmonella Typhimurium detection

    Energy Technology Data Exchange (ETDEWEB)

    Peng-Ubol, Triranat [Department of Chemistry, Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Phinyocheep, Pranee, E-mail: scppo@mahidol.ac.th [Department of Chemistry, Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Daniel, Philippe [Laboratoire de Physique de l' Etat Condense (LPEC-UMR CNRS 6087), Universite du Maine, Avenue Olivier Messiaen, 72085, Le Mans Cedex 9 (France); Panbangred, Watanalai [Department of Biotechnology and Mahidol University-Osaka University Collaborative Research Center for Bioscience and Biotechnology (MU-OU: CRC), Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Pilard, Jean-Francois [Unite de Chimie Organique Moleculaire et Macromoleculaire (UCO2M-UMR CNRS 6011), Universite du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Thouand, Gerald; Durand-Thouand, Marie-Jose [Genie des Procedes Environnement et Agroalimentaire (GEPEA UMR CNRS 6144), Departement Genie Biologique, IUT de la Roche/Yon, Universite de Nantes, 18 Bd G. Defferre, 85035 La Roche sur Yon (France)

    2012-12-01

    Salmonella is a major cause of foodborne illness worldwide and is not allowed to be present in any food in all countries. The purpose of this study is to develop a simple alternative method for the detection of Salmonella based on functionalized polyethylene (PE) surfaces. Salmonella Typhimurium was used as a model bacterium. PE film was treated using dielectric plasma in order to alter the wettability of the PE surface and consequently introduce functionality on the surface. The PE film characterized by ATR-FTIR spectroscopy revealed the presence of C=O stretching of ketones, aldehydes and carboxylic acids. The antibodies against O or H antigens of Salmonella and S. Typhimurium were then respectively immobilized on the PE surface after activation of the carboxylic group using NHS/EDC followed by protein A. The evidences from ATR-FTIR, scanning electron microscopy and optical microscopy showed the presence of S. Typhimurium attached to the plasma treated PE surfaces via the two types of anti-Salmonella antibody. The plasma treated PE film developed is simple and allows efficient association of bacterial cells on the treated surfaces without the necessity of time-consuming centrifugation and washing steps for isolation of the cells. This material is considered to be a smart material applicable for S. Typhimurium detection. Highlights: Black-Right-Pointing-Pointer We developed a functionalized polyethylene film for bacterial detection. Black-Right-Pointing-Pointer We modified the surface of polyethylene film by plasma treatment. Black-Right-Pointing-Pointer ATR-FTIR spectroscopy was used to analyze the functionality on the PE surface. Black-Right-Pointing-Pointer We introduced Salmonella Typhimurium on the modified PE film. Black-Right-Pointing-Pointer SEM revealed the presence of S. Typhimurium on the plasma treated PE film.

  9. Plasma-treated polyethylene film: A smart material applied for Salmonella Typhimurium detection

    International Nuclear Information System (INIS)

    Peng-Ubol, Triranat; Phinyocheep, Pranee; Daniel, Philippe; Panbangred, Watanalai; Pilard, Jean-François; Thouand, Gerald; Durand-Thouand, Marie-José

    2012-01-01

    Salmonella is a major cause of foodborne illness worldwide and is not allowed to be present in any food in all countries. The purpose of this study is to develop a simple alternative method for the detection of Salmonella based on functionalized polyethylene (PE) surfaces. Salmonella Typhimurium was used as a model bacterium. PE film was treated using dielectric plasma in order to alter the wettability of the PE surface and consequently introduce functionality on the surface. The PE film characterized by ATR-FTIR spectroscopy revealed the presence of C=O stretching of ketones, aldehydes and carboxylic acids. The antibodies against O or H antigens of Salmonella and S. Typhimurium were then respectively immobilized on the PE surface after activation of the carboxylic group using NHS/EDC followed by protein A. The evidences from ATR-FTIR, scanning electron microscopy and optical microscopy showed the presence of S. Typhimurium attached to the plasma treated PE surfaces via the two types of anti-Salmonella antibody. The plasma treated PE film developed is simple and allows efficient association of bacterial cells on the treated surfaces without the necessity of time-consuming centrifugation and washing steps for isolation of the cells. This material is considered to be a smart material applicable for S. Typhimurium detection. Highlights: ► We developed a functionalized polyethylene film for bacterial detection. ► We modified the surface of polyethylene film by plasma treatment. ► ATR-FTIR spectroscopy was used to analyze the functionality on the PE surface. ► We introduced Salmonella Typhimurium on the modified PE film. ► SEM revealed the presence of S. Typhimurium on the plasma treated PE film.

  10. k-Carrageenan/poly vinyl pyrollidone/polyethylene glycol/silver nanoparticles film for biomedical application.

    Science.gov (United States)

    Fouda, Moustafa M G; El-Aassar, M R; El Fawal, G F; Hafez, Elsayed E; Masry, Saad Hamdy Daif; Abdel-Megeed, Ahmed

    2015-03-01

    Biopolymer composite film containing k-carrageenan (KC), polyvinyl pyrrolidone (PVP), and polyethylene glycol (PEG) was formulated by dissolving KC and PVP in water containing PEG. Silver nanoparticles (AgNPs), was produced by Honeybee and added to solution. Finally, all solutions were poured onto dishes and dried overnight at 40°C to form the final films. Tensile strength (TS) and elongation (E %) is evaluated. The water contact angle is inspected. Thermal properties (TGA) and swelling behavior for water were considered. Fungal activity is also examined. Morphology of all films was also explored using scanning electron microscope. AgNPs induced significant hydrophilicity to KC-PVP-PEG film with contact angle of 41.6 and 34.7 for KC-PVP-PEG-AgNPs. Films with AgNPs exhibited higher thermal stability and strength properties than other films without. Films with AgNPs explore lower swelling behavior than other films without. Both SEM and EDX proved the deposition of AgNPs on the surface of films. Films with AgNPs showed higher activity against pathogenic fungi compared with the chemical fungicide; fluconazole. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Unique Crystal Orientation of Poly(ethylene oxide) Thin Films by Crystallization Using a Thermal Gradient

    DEFF Research Database (Denmark)

    Gbabode, Gabin; Delvaux, Maxime; Schweicher, Guillaume

    2017-01-01

    Poly(ethylene oxide), (PEO), thin films of different thicknesses (220, 450, and 1500 nm) and molecular masses (4000, 8000, and 20000 g/mol) have been fabricated by spin-coating of methanol solutions onto glass substrates. All these samples have been recrystallized from the melt using a directional......, to significantly decrease the distribution of crystal orientation obtained after crystallization using the thermal gradient technique....

  12. Artificial ageing of tri-layer polyethylene film used as greenhouse cover under the effect of the temperature and the UV-A simultaneously

    International Nuclear Information System (INIS)

    Dehbi, Abdelkader; Bouaza, Amar; Hamou, Ahmed; Youssef, Boulos; Saiter, Jean Marc

    2010-01-01

    This study helps to understand the mechanism of artificial ageing of a tri-layer film made of low-density polyethylene (LDPE) 'Agrofilm' with additives (color dye, UV and IR stabilizers) used as greenhouse cover under the variations of the temperature with or without UV-A radiations. Ageing was monitored by observing the change of physical properties (free surface energy, color) mechanical and structural effects (Tensile tests, DSC, FTIR) during 5486 h (almost 8 months). The study shows that increase in the free surface energy is proportional to the temperature and that the increase is more pronounced when the film is subjected to the combined action of the temperature and the UV-A radiations. The mechanical tests reveal that both elongation at break and yield stress decrease with the ageing. The calorific curves exhibit two endothermic peaks of melting close together (100 o C and 110 o C) which means the presence in the film of at least two types of crystalline structures. From free surface energy results, the life time of these films under artificial conditions is estimated to 12 months when exposed to 40 o C but drops to 3 months and 18 days when exposed simultaneously to 50 o C and UV-A.

  13. Preparation and Characterization of Some Polyethylene Modified- Starch Biodegradable Films

    International Nuclear Information System (INIS)

    Badrana, A.S.; Ramadanb, A.M.; Ibrahim, N.A.; Kahild, T.; Hussienc, H.A.

    2005-01-01

    Blends of LDPE with soluble starch, wheat flour and commercial starch were prepared by mixing starch (or flour) with styrene then blending the mixture with LDPE, The starch percents vary between 5 and 50% of the total weight. Their physical and mechanical properties were recorded and compared with pure LDPE. It was observed that the increase in starch or wheat flour contents of the mixture was reversibly proportional to the tensile strength and % elongation. Samples were tested for water absorption. All of the samples were insoluble in cold and boiling water. Moisture uptake increased with immersion time and increasing starch content. The changes in the tensile strength of LDPE/starch (or wheat flour) after the course of thermal oxidation was measured. These results show negligible changes in the tensile strength of the control sample as compared to that of the samples containing the additives. Oxidation processes take advantage of the high temperatures (40-50 degree C) and the time. It was also observed that after 10 weeks of soil burial, the mechanical properties of the films decrease, mainly, due to starch removal from the films. Also, for the weight loss a drastic decrease was observed after 10 weeks of soil burial thereafter it preceded slowly. The LDPE/ starch strips showed weight loss after treating with a-amylase this due to hydrolysis and leaching of the starch. The rate of starch hydrolysis increases with the increase in starch content of the sample. The influence of addition of starch on the overall migration of these films, with different food simulant, was studied, at different temperatures (-4 degree. 25 degree and 40 degree C). All values were significantly lower than the upper limit for overall migration set by the EU (10 mg/dirf) for food grade plastics packaging materials

  14. Physical Characteristics of Chitosan Based Film Modified With Silica and Polyethylene Glycol

    Directory of Open Access Journals (Sweden)

    F. Widhi Mahatmanti

    2014-07-01

    Full Text Available Recently, development of film materials is focused on finding the films with high chemical and physical stabilities. Organic based material such as chitosan produces films with low physical stability, and hence addition of inorganic materials necessary. In this research, the effect of silica and polyethylene glycol (PEG addition on the properties of chitosan based films has been investigated. Precursors used to produce films included chitosan with the deacetylation degree of 83% and sodium silicate solution as the silica source. A simple synthesis in a one-pot process was carried out by mixing 1%(w of chitosan solution in 2%(v/v acetate acid and sodium silicate solution (27% SiO2 in various composition ratios and casting the solution on a glass dish. The tensile strength and percentage of elongation decrease with increasing the silica content. The tensile strength tends to decline with addition of PEG, but the elongation percentage of the film increases. Hydrophilicity of the film decreases with the addition of silica and increases with the addition of PEG. The addition of silica and PEG does not change significantly the morphology of the film and functional groups indicating the domination of physical interaction among active sites in the film components.

  15. Solid-phase photocatalytic degradation of polyethylene film with manganese oxide OMS-2

    Science.gov (United States)

    Liu, Guanglong; Liao, Shuijiao; Zhu, Duanwei; Cui, Jingzhen; Zhou, Wenbing

    2011-01-01

    Solid-phase photocatalytic degradation of polyethylene (PE) film with cryptomelane-type manganese oxide (OMS-2) as photocatalyst was investigated in the ambient air under ultraviolet and visible light irradiation. The properties of the composite films were compared with those of the pure PE film through performing weight loss monitoring, IR spectroscopy, scanning electron microscopic (SEM) and X-ray photoelectron spectroscopy (XPS). The photoinduced degradation of PE-OMS-2 composite films was higher than that of the pure films, while there has been little change under the visible light irradiation. The weight loss of PE-OMS-2 (1.0 wt%) composite films steadily decreased and reached 16.5% in 288 h under UV light irradiation. Through SEM observation there were some cavities on the surface of composite films, but few change except some surface chalking phenomenon occurred in pure PE film. The degradation rate with ultraviolet irradiation is controllable by adjusting the content of OMS-2 particles in PE plastic. Finally, the mechanism of photocatalytic degradation of the composite films was briefly discussed.

  16. Solid-phase photocatalytic degradation of polyethylene-goethite composite film under UV-light irradiation

    International Nuclear Information System (INIS)

    Liu, G.L.; Zhu, D.W.; Liao, S.J.; Ren, L.Y.; Cui, J.Z.; Zhou, W.B.

    2009-01-01

    A novel photodegradable polyethylene-goethite (PE-goethite) composite film was prepared by embedding the goethite into the commercial polyethylene. The degradation of PE-goethite composite films was investigated under ultraviolet light irradiation. The photodegradation activity of the PE plastic was determined by monitoring its weight loss, scanning electron microscopic (SEM) analysis and FT-IR spectroscopy. The weight of PE-goethite (1 wt%) sample steadily decreased and led to the total 16% reduction in 300 h under UV-light intensity for 1 mW/cm 2 . Through SEM observation there were some cavities around the goethite powder in the composite films, but there were few changes except some surface chalking phenomenon in pure PE film. The degradation rate could be controlled by changing the concentration of goethite particles in PE plastic. The degradation of composite plastic initiated on PE-goethite interface and then extended into polymer matrix induced by the diffusion of the reactive oxygen species generated on goethite particle surface. The photocatalytic degradation mechanism of the composite films was briefly discussed.

  17. Adsorption of anionic surfactant on porous and nonporous polyethylene terephthalate films

    International Nuclear Information System (INIS)

    Yamauchi, Yu.; Apel, P.Yu.

    2016-01-01

    We study the adsorption of anionic surfactant, sodium dodecyl diphenyloxide disulfonate (SDDD) on three types of polyethylene terephthalate (PET) substrates from aqueous solutions of SDDD of different concentrations. Neutral electrolyte (KCl) was added to the solutions to vary the ionic strength. Three types of substrates were used: 1) original PET film; 2) etched nonporous film, obtained from pristine film by chemical etching and bearing negative charge on the surface; 3) etched porous membranes, fabricated from pristine film by ion irradiation and subsequent chemical etching. The membranes have negative charge on the flat surface and on the inner pore walls. The comparison shows that the negative charge on the flat surface has weak effect on adsorption of the anionic surfactant, and the SDDD adsorption on the inner walls of pores is much weaker than on flat surface, even if the pore radius is significantly larger than the Debye length. This «exclusion» effect strongly depends on ionic strength of solution. [ru

  18. Preparation of chitosan-coated polyethylene packaging films by DBD plasma treatment.

    Science.gov (United States)

    Theapsak, Siriporn; Watthanaphanit, Anyarat; Rujiravanit, Ratana

    2012-05-01

    Polyethylene (PE) packaging films were coated with chitosan in order to introduce the antibacterial activity to the films. To augment the interaction between the two polymers, we modified the surfaces of the PE films by dielectric barrier discharge (DBD) plasma before chitosan coating. After that the plasma-treated PE films were immersed in chitosan acetate solutions with different concentrations of chitosan. The optimum plasma treatment time was 10 s as determined from contact angle measurement. Effect of the plasma treatment on the surface roughness of the PE films was investigated by atomic force microscope (AFM) while the occurrence of polar functional groups was observed by X-ray photoelectron spectroscope (XPS) and Fourier transformed infrared spectroscope (FTIR). It was found that the surface roughness as well as the occurrence of oxygen-containing functional groups (i.e., C═O, C-O, and -OH) of the plasma-treated PE films increased from those of the untreated one, indicating that the DBD plasma enhanced hydrophilicity of the PE films. The amounts of chitosan coated on the PE films were determined after washing the coated films in water for several number of washing cycles prior to detection of the chitosan content by the Kjaldahl method. The amounts of chitosan coated on the PE films were constant after washing for three times and the chitosan-coated PE films exhibited appreciable antibacterial activity against Escherichia coli and Staphylococcus aureus. Hence, the obtained chitosan-coated PE films could be a promising candidate for antibacterial food packaging.

  19. Effect of forming temperature conditions on the properties of radiation laced polyethylene films

    Energy Technology Data Exchange (ETDEWEB)

    Trizno, M S; Gasparyan, K A; Arutyunyan, G V; Borovko, V N

    1978-11-01

    The effect of radiation lace on the thermomechanical properties of polyethylene films depending on the radiation dose and temperature conditions of their formation was studied. The samples were produced at 160 deg under the pressure of 150 kN/m/sup 2/ with the following cooling in two temperature conditions: 1) cooling of the sample just after pressing in the icy water, and 2) slow cooling of the sample in a press. Films obtained using above conditions were subjected to the radiation lace in the argon medium using ..gamma..-radiation of /sup 60/Co at the exposure dose of 0.8x10/sup 6/ rad/hr. The total radiation dose was from 30 to 200 Mrad. It is shown that the films, obtained under the first cooling conditions have a lower degree of crystallinity. Investigations of gel-fraction content, density, elastic modulus, deformability, modulus of high elasticity, breaking stress, and relative elongation for rupture depending on radiation doze and the degree of crystallinity have shown that minimum degree of crystallinity of initial films provided most uniform adn compact net structure in the laced polyethylene(LP). In this case the material working capacity increases at high temperatures. In order to improve the mechanical properties of LP when exploiting it in the amorphous crystalline state it is recommended to irradiate material with maximum degree of crystallinity.

  20. 76 FR 22867 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates: Final Results of...

    Science.gov (United States)

    2011-04-25

    ... Film, Sheet, and Strip From the United Arab Emirates: Final Results of Antidumping Duty Administrative...) from the United Arab Emirates. This review covers two producers/ exporters of subject merchandise: JBF... Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates: Preliminary Results of...

  1. 76 FR 45508 - Polyethylene Terephthalate Film, Sheet and Strip From the United Arab Emirates: Extension of Time...

    Science.gov (United States)

    2011-07-29

    ... Film, Sheet and Strip From the United Arab Emirates: Extension of Time Limit for Preliminary Results of... polyethylene terephthalate film, sheet and strip from the United Arab Emirates (UAE) for the period November 01... producer and/or exporter of the subject merchandise to the United States: JBF RAK LLC (JBF). Extension of...

  2. Surface morphology of polyethylene glycol films produced by matrix-assisted pulsed laser evaporation (MAPLE): Dependence on substrate temperature

    DEFF Research Database (Denmark)

    Rodrigo, K.; Czuba, P.; Toftmann, B.

    2006-01-01

    The dependence of the surface morphology on the substrate temperature during film deposition was investigated for polyethylene glycol (PEG) films by matrix-assisted pulsed laser evaporation (MAPLE). The surface structure was studied with a combined technique of optical imaging and AFM measurements...

  3. Surface characterization of polyethylene terephthalate films treated by ammonia low-temperature plasma

    International Nuclear Information System (INIS)

    Zheng Zhiwen; Ren Li; Feng Wenjiang; Zhai Zhichen; Wang Yingjun

    2012-01-01

    In order to study the surface characterization and protein adhesion behavior of polyethylene terephthalate film, low temperature ammonia plasma was used to modify the film. Effects of plasma conditions of the surface structures and properties were investigated. Results indicated that surface hydrophilicity of polyethylene terephthalate was significantly improved by ammonia plasma treatment. Ammonia plasma played the role more important than air treatment in the process of modification. Furthermore, by Fourier Transform Infrared spectra some new bonds such as -N=O and N-H which could result in the improvement of the surface hydrophilicity were successfully grafted on the film surface. Atom force microscope experiments indicated that more protein adsorbed on hydrophobic surfaces than hydrophilic ones, and the blobs arranged in a straight line at etching surface by plasma. Modified membrane after ammonia plasma treatment had a good cell affinity and could be effective in promoting the adhesion and growth of cells on the material surface. Timeliness experiments showed that the plasma treatment gave the material a certain performance only in a short period of time and the hydrophobicity recovered after 12 days.

  4. Modification of polyethylene films by radiation grafting of glycidyl methacrylate and immobilization of {beta}-cyclodextrin

    Energy Technology Data Exchange (ETDEWEB)

    Nava-Ortiz, C.A.B. [Departamento de Quimica de Radiaciones y Radioquimica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, Mexico DF 04510 (Mexico); Burillo, G. [Departamento de Quimica de Radiaciones y Radioquimica, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Circuito Exterior, 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, Circuito Exterior, Ciudad Universitaria, Mexico DF 04510 (Mexico); Alvarez-Lorenzo, C. [Departamento de Farmacia y Tecnologia Farmaceutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela (Spain)

    2009-01-15

    Glycidyl methacrylate was grafted onto polyethylene films using a preirradiation method with {gamma} rays. The effect of absorbed dose, monomer concentration, and reaction time on the degree of grafting was determined. The grafted samples were verified by FTIR-ATR spectroscopy. {beta}-Cyclodextrin was immobilized onto polypropylene modified with glycidyl methacrylate, and the ability of the cavities of {beta}-cyclodextrin to form inclusion complexes was demonstrated using the typically organic compound approach with m-toluic acid (3-MBA) as a probe.

  5. A thin alanine-polyethylene film dosimetry system with diffuse reflection spectrophotometric evaluation

    International Nuclear Information System (INIS)

    Zagorski, Z.P.; Rafalski, A.

    1995-01-01

    Characteristics of a new alanine dosimeter in the shape of a thin film, with the measurement of optical absorption of the CH 3 CHCOO - radical is described. That type of dosimeter, ALA/DRS (for diffuse reflection spectrophotometry) is compared, to an alanine dosimeter with EPR evaluation (ALA/EPR for short). In many respects the simple ALA/DRS version, as the alanine-polyethylene composite is superior. The paper shows the importance of the new experimental approach to free radical research in solid state radiation chemistry. (author). 7 refs., 3 figs

  6. Interfacial characteristics of polyethylene terephthalate-based piezoelectric multi-layer films

    International Nuclear Information System (INIS)

    Liu, Z.H.; Pan, C.T.; Chen, Y.C.; Liang, P.H.

    2013-01-01

    The study examines the deformation between interfaces and the adhesion mechanism of multi-layer flexible electronic composites. Indium tin oxide (ITO), aluminum (Al), and zinc oxide (ZnO) were deposited on a polyethylene terephthalate (PET) substrate using radio frequency magnetron sputtering at room temperature to form flexible structures (e.g., ITO/PET, Al/PET, ZnO/ITO/PET, and ZnO/Al/PET) for piezoelectric transducers. ITO and Al films are used as the conductive layers. A ZnO thin film shows a high (002) c-axis preferred orientation at 2θ = 34.45° and excellent piezoelectric properties. Nanoscratching and nano-indention testing were conducted to analyze the adhesion following periodic mechanical stress. Additionally, two Berkovich and conical probes with a curvature radius of 40 nm and 10 μm are examined for the scratching test. A 4-point probe is used to measure the conductive properties. The plastic deformation between the ductile Al film and PET substrate is observed using scanning electron microscopy to examine the chip formation on the ITO/PET. Delamination between the ZnO and Al/PET substrate was not observed. The result suggests that ZnO film has excellent adhesion with Al/PET compared to ITO/PET. - Highlights: ► Interfaces and adhesion mechanism of multi-layer flexible electronic composites ► Polyethylene terephthalate (PET) based flexible structures ► Nano-scratching and nano-indention tests were used to analyze adhesion. ► Using two various probes of Berkovich and conical ► Piezoelectric zinc oxide film has excellent adhesion with aluminum/PET

  7. Microbial status, aerobic stability and fermentation of maize silage sealed with an oxygen barrier film or standard polyethylene film

    Directory of Open Access Journals (Sweden)

    Szilvia Orosz

    2013-03-01

    Full Text Available An experiment was conducted to compare a bunker silo sealing system comprising an oxygen barrier film (OB: 45μm thickness with protective woven polypropylene with one comprising standard black polyethylene film (S; 125μm thickness with protective tyres. Analysis of samples taken to 30 cm depth after 365 days of storage showed no differences in pH or lactic acid between the two sealing systems. There were no differences in aerobic bacterial count between silages. Whilst 2.56 log10 CFU moulds g-1 fresh weight were found in samples of silage sealed with S, no moulds were found in samples of silage sealed with OB. Aerobic stability, averaged 249 hours and 184 hours for OB and S, respectively. The OB system probably inhibited the development of the micro-organisms responsible for the initiation of aerobic deterioration to a greater extent than the standard silo sealing system.  

  8. Poly(ethylene glycol)/carbon quantum dot composite solid films exhibiting intense and tunable blue–red emission

    International Nuclear Information System (INIS)

    Hao, Yanling; Gan, Zhixing; Xu, Jiaqing; Wu, Xinglong; Chu, Paul K.

    2014-01-01

    Highlights: • Poly(ethylene glycol)/carbon quantum dots (PEG/CQDs) composite solid films exhibiting strong and tunable blue–red emission were prepared. Successful preparation of tunable emitting CQDs solid films can extend the application of carbon quantum dots in photoelectric devices. • The mechanism of the tunable emission from the PEG/CQDs composite solid films was discussed. • On the basis of the characteristics of the PL from solid films in this work, the complex PL origins of CQDs were further defined. The PL mechanism provides insights into the fluorescence mechanism of CQDs and may promotes their applications. • Poly(ethylene glycol); carbon quantum dots; Strong and tunable blue-red emission; The fluorescent quantum yield of 12.6%. - Abstract: Although carbon quantum dots (CQDs) possess excellent luminescence properties, it is a challenge to apply water-soluble CQDs to tunable luminescent devices. Herein, quaternary CQDs are incorporated into poly(ethylene glycol) to produce poly(ethylene glycol)/CQD composite solid films which exhibit strong and tunable blue–red emission. The fluorescent quantum yield reaches 12.6% which is comparable to that of many liquid CQDs and the photoluminescence characteristics are determined to elucidate the fluorescence mechanism. The CQD solid films with tunable optical properties bode well for photoelectric devices especially displays

  9. Effect of [gamma]-irradiation on latent tracks of polyethylene terephthalate (PET) film

    Science.gov (United States)

    Hiroki, A.; Asano, M.; Yamaki, T.; Yoshida, M.

    2005-04-01

    The pre-treatment effect of γ-irradiation on latent tracks of polyethylene terephthalate (PET) films bombarded with swift heavy ions was investigated by electric conductometry and scanning electron microscope (SEM) observation. The Xe-ion bombarded PET films were etched for 6 h in 0.2 M NaOH aqueous solution at 70 °C to prepare track-etched membranes. As γ-irradiation doses increased in the range of 0-160 kGy, the surface pore diameter obtained by SEM observation decreased while that obtained by conductometry became large. This inconsistent result between the two methods was due to an increase in the crosslinked region in the latent tracks caused by γ-irradiation.

  10. High gamma dose response of the electrical properties of polyethylene terephthalate thin films

    International Nuclear Information System (INIS)

    Radwan, R.M.

    2007-01-01

    Electrical properties of polyethylene terephthalate (PET), irradiated with gamma rays, have been investigated. The PET films were irradiated with high gamma dose levels in the range from 100 to 2000 kGy. The changes in the DC (σ DC ) and the ac (σ ac ) conductivities, with the dose, have been performed. The effect of gamma irradiation on the dielectric constant (ε') and loss (ε'') has been determined. Also, the dose dependence of the frequency exponent index (S), the resonance frequency (Fc) and the hopping frequency (ω P ) have been obtained. The obtained results show that increasing gamma dose leads to slight increase in σ DC , σ ac and ε', while no change was observed in ε'' value. Meanwhile, S, Fc and ω P are inversely proportional to the dose. Accordingly, the study suggests the possibility of using PET films in electronic components (capacitors, resistors, etc.), especially that operate at high gamma dose environments for the frequency independent applications

  11. Study of microstructure of modified polyethylene films with acrylic and methacrylic acids, by positron annihilation spectroscopy

    International Nuclear Information System (INIS)

    Lopez C, R.

    1995-09-01

    Low density polyethylene (LDPE) was preirradiated with γ -rays and after some contact time with the monomers AA and MAA, suitable graft copolymers were obtained at different grafting grades. After their physical-chemistry characterization, the copolymers were studied using the Positron Annihilation Lifetime Spectroscopy (PALS). Owing to its sensitive and non-destructive nature PALS has proven to be very useful in studying free-volume properties -at the molecular level- during phase transitions in molecular solids, such as the graft copolymers of LDPE/AA and LDPE/MAA. Using PALS it was possible to detect the changes in the melting point of the LDPE as a function of the grafting degree, obtaining thus, valuable information about the microstructure of this kind of copolymers. The increase in the values of the o-Ps lifetime, was interpreted as suggesting that the melting transition is followed by a free-volume cavity expansion as the temperature increased. The o-Ps intensity of formation behavior is in accord with the distortions occurring in the electronic density surrounding the o-Ps as well as the changes in the number of cavities available to the formation of o-Ps. (Author)

  12. Gas barrier properties of titanium oxynitride films deposited on polyethylene terephthalate substrates by reactive magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Lin, M.-C. [Department of Materials Science and Engineering, National ChungHsin University, 250, Kuo-Kung Road, 40227 Taichung, Taiwan (China); Chang, L.-S. [Department of Materials Science and Engineering, National ChungHsin University, 250, Kuo-Kung Road, 40227 Taichung, Taiwan (China)], E-mail: lschang@dragon.nchu.edu.tw; Lin, H.C. [Department of Materials Science and Engineering, National Taiwan University, 1, Roosevelt Road, Sec. 4, 106 Taipei, Taiwan (China)

    2008-03-30

    Titanium oxynitride (TiN{sub x}O{sub y}) films were deposited on polyethylene terephthalate (PET) substrates by means of a reactive radio frequency (RF) magnetron sputtering system in which the power density and substrate bias were the varied parameters. Experimental results show that the deposited TiN{sub x}O{sub y} films exhibited an amorphous or a columnar structure with fine crystalline dependent on power density. The deposition rate increases significantly in conjunction as the power density increases from 2 W/cm{sup 2} to 7 W/cm{sup 2}. The maximum deposition rate occurs, as the substrate bias is -40 V at a certain power densities chosen in this study. The film's roughness slightly decreases with increasing substrate bias. The TiN{sub x}O{sub y} films deposited at power densities above 4 W/cm{sup 2} show a steady Ti:N:O ratio of about 1:1:0.8. The water vapor and oxygen transmission rates of the TiN{sub x}O{sub y} films reach values as low as 0.98 g/m{sup 2}-day-atm and 0.60 cm{sup 3}/m{sup 2}-day-atm which are about 6 and 47 times lower than those of the uncoated PET substrate, respectively. These transmission rates are comparable to those of DLC, carbon-based and Al{sub 2}O{sub 3} barrier films. Therefore, TiN{sub x}O{sub y} films are potential candidates to be used as a gas permeation barrier for PET substrate.

  13. Bio-based biodegradable film to replace the standard polyethylene cover for silage conservation.

    Science.gov (United States)

    Borreani, Giorgio; Tabacco, Ernesto

    2015-01-01

    The research was aimed at studying whether the polyethylene (PE) film currently used to cover maize silage could be replaced with bio-based biodegradable films, and at determining the effects on the fermentative and microbiological quality of the resulting silages in laboratory silo conditions. Biodegradable plastic film made in 2 different formulations, MB1 and MB2, was compared with a conventional 120-μm-thick PE film. A whole maize crop was chopped; ensiled in MB1, MB2, and PE plastic bags, 12.5kg of fresh weight per bag; and opened after 170d of conservation. At silo opening, the microbial and fermentative quality of the silage was analyzed in the uppermost layer (0 to 50mm from the surface) and in the whole mass of the silo. All the silages were well fermented with little differences in fermentative quality between the treatments, although differences in the mold count and aerobic stability were observed in trial 1 for the MB1 silage. These results have shown the possibility of successfully developing a biodegradable cover for silage for up to 6mo after ensiling. The MB2 film allowed a good silage quality to be obtained even in the uppermost part of the silage close to the plastic film up to 170d of conservation, with similar results to those obtained with the PE film. The promising results of this experiment indicate that the development of new degradable materials to cover silage till 6mo after ensiling could be possible. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  14. Effect of solubility parameter of solvents on electron beam induced graft-polymerization onto polyethylene films

    International Nuclear Information System (INIS)

    Mori, Koji; Koshiishi, Kenji; Masuhara, Ken-ichi

    1992-01-01

    Electron beam induced graft-polymerization by the mutual irradiation technique of methyl methacrylate (MMA) and methacrylic acid (MAAc) blended with solvents, which have different solubility parameters δ, onto high density polyethylene films (PE) were investigated at high dose rates (25 Mrad per second). Graft-polymerization mechanisms were discussed on the basis of grafting rates, surface tensions, atomic rations on the surface by XPS, and SEM images of the grafted films. Grafting rates decreased with increasing δ of solvents, and grafting rates for MMA were larger than those for MAAc. Graft chain contents on the surface, which were evaluated in terms of surface tensions and atomic ratios on the surface, increased with increasing δ of solvents, and graft chain contents on the surface of MAAc grafted PE were higher than those of MMA grafted PE. It is assumed that mutual solubility of PE and solvents (monomer solutions), i.e., infiltration of monomer solutions into PE during graft-polymerization, influenced grafting rates and graft sites in films. In case of high mutual solubility, grafting rates were large and graft sites spread from the surface into bulk. On the other hand, in case of low mutual solubility, grafting rates were small and graft sites localized on the surface of films. (author)

  15. Metal adsorption of gamma-irradiated carboxymethyl cellulose/polyethylene oxide blend films

    Science.gov (United States)

    El-Naggar, Amal A.; Magida, M. M.; Ibrahim, Sayeda M.

    2016-03-01

    Blend films of different ratios of carboxymethyl cellulose (CMC)/polyethylene oxide (PEO) were prepared by the solution casting method. To investigate the effect of irradiation on all properties of prepared blend, it was exposed to different gamma irradiation doses (10, 20, and 30 kGy). Physical properties such as gel fraction (GF) (%) and swelling (SW) (%) were investigated. It was found that the GF (%) increases with increasing irradiation dose up to 20 kGy, while SW (%) decreases with an increase in the irradiation doses for all blend compositions. Moreover, the structural and mechanical properties of the prepared films were studied. The results of the mechanical properties obtained showed that there is an improvement in these properties with an increase in both CMC and irradiation dose up to 20 kGy. The efficiency of metal ions uptake was measured using a UV spectrophotometer. The prepared films showed good tendency to absorb and release metal ions from aqueous media. Thus, the CMC/PEO film can be used in agricultural domain.

  16. The Effects of Gas Composition on the Atmospheric Pressure Plasma Jet Modification of Polyethylene Films

    International Nuclear Information System (INIS)

    Sun Jie; Qiu Yiping

    2015-01-01

    Polyethylene (PE) films are treated using an atmospheric pressure plasma jet (APPJ) with He or He/O 2 gas for different periods of time. The influence of gas type on the plasma-polymer interactions is studied. The surface contact angle of the PE film can be effectively lowered to 58° after 20 s of He/O 2 plasma treatment and then remains almost unchanged for longer treatment durations, while, for He plasma treatment, the film surface contact angle drops gradually to 47° when the time reaches 120 s. Atomic force microscopy (AFM) results show that the root mean square (RMS) roughness was significantly higher for the He/O 2 plasma treated samples than for the He plasma treated counterparts, and the surface topography of the He/O 2 plasma treated PE films displays evenly distributed dome-shaped small protuberances. Chemical composition analysis reveals that the He plasma treated samples have a higher oxygen content but a clearly lower percentage of −COO than the comparable He/O 2 treated samples, suggesting that differences exist in the mode of incorporating oxygen between the two gas condition plasma treatments. Electron spin resonance (ESR) results show that the free radical concentrations of the He plasma treated samples were clearly higher than those of the He/O 2 plasma treated ones with other conditions unchanged. (paper)

  17. Re-usable low density polyethylene arm glove for puerperal ...

    African Journals Online (AJOL)

    Objective: To design a long arm glove that can be used within a puerperal uterus to prevent the health-care worker contracting HIV from an infected patient. The designed long arm glove should be cheap (affordable) and readily available in low resource centres and must have proven sterility assurance and tensile strength ...

  18. Linear low density polyethylene/cycloolefin copolymer blends

    Czech Academy of Sciences Publication Activity Database

    Dorigato, A.; Pegoretti, A.; Fambri, L.; Lonardi, C.; Šlouf, Miroslav; Kolařík, Jan

    2011-01-01

    Roč. 5, č. 1 (2011), s. 23-37 ISSN 1788-618X R&D Projects: GA ČR GA106/09/1348 Institutional research plan: CEZ:AV0Z40500505 Keywords : polymer blends * cycloolefin copolymer * creep Subject RIV: JI - Composite Materials Impact factor: 1.769, year: 2011

  19. Potential of using recycled low-density polyethylene in wood ...

    African Journals Online (AJOL)

    use

    the requirement. Hence this LDPE can be used in board production for general purpose applications. ... can be manufactured in different sizes, thickness, densities and grades ..... mined not only by usual design parameters, but by its impact or ...

  20. Influence of UV-Irradiation on Latent Tracks in Polyethylene Terephthalate Films

    International Nuclear Information System (INIS)

    Wen Qi; Wang Peng-Fei; Ling Yun; Wang Mao; Yan Dong-Xiao; Wang Yu-Gang; Cao Xing-Zhong; Wang Bao-Yi

    2016-01-01

    Polyethylene terephthalate (PET) films in thickness of 12 μm are irradiated by Xe and Au ions at the energies of 9.5 and 11.4MeV/u and with the ion fluence from 5 × 10"9 cm"−"2 to 1 × 10"1"1 cm"−"2. After irradiation, ultra-violet lights are used to illuminate the samples with latent tracks at the wavelength of 365 nm with flux density of 4.2 mW/cm"−"2. UV-irradiation effects on tracked PET are investigated by the UV-vis spectrum and positron annihilation lifetime spectroscopy (PALS). It is found that carbonaceous clusters in PET films are generated by ion irradiation and decomposed with UV illumination by calculating the optical energy band gap E_g in the UV-vis spectrum. The free volumes behave differently in track and bulk after UV illumination. In our experiment, the PALS results show an increase in radius and density of free volume in tracked PET films after UV treatment, which indicates an expansion in radius of latent tracks. (paper)

  1. Thin-film type Li-ion battery, using a polyethylene separator grafted with glycidyl methacrylate

    International Nuclear Information System (INIS)

    Ko, J.M.; Min, B.G.; Kim, D.-W.; Ryu, K.S.; Kim, K.M.; Lee, Y.G.; Chang, S.H.

    2004-01-01

    For the improvement of organic electrolyte holding ability, the hydrophobic surface of a porous polyethylene (PE)-membrane separator was modified by grafting a hydrophilic monomer, glycidyl methacrylate (GMA), PE-g-GMA, by using electron beam technology, and applied to a thin film type Li-ion battery to elucidate the effect of a surface modification of a PE membrane separator on the cyclic life of Li-ion batteries. The Li-ion battery using the PE-g-GMA membrane separator showed a better cycle life than that of the unmodified PE membrane separator, indicating that the surface hydrophilicity of the PE membrane separator improved the electrolyte holding capability between the electrodes in the Li-ion cell and prevented the electrolyte leakage

  2. Effects of annealing temperature on mechanical durability of indium-tin oxide film on polyethylene terephthalate substrate

    International Nuclear Information System (INIS)

    Machinaga, Hironobu; Ueda, Eri; Mizuike, Atsuko; Takeda, Yuuki; Shimokita, Keisuke; Miyazaki, Tsukasa

    2014-01-01

    Effects of the annealing temperature on mechanical durability of indium-tin oxide (ITO) thin films deposited on polyethylene terephthalate (PET) substrates were investigated. The ITO films were annealed at the range from 150 °C to 195 °C after the DC sputtering deposition for the production of polycrystalline ITO layers on the substrates. The onset strains of cracking in the annealed ITO films were evaluated by the uniaxial stretching tests with electrical resistance measurements during film stretching. The results indicate that the onset strain of cracking in the ITO film is clearly increased by increasing the annealing temperature. The in-situ measurements of the inter-planer spacing of the (222) plane in the crystalline ITO films during film stretching by using synchrotron radiation strongly suggest that the large compressive stress in the ITO film increases the onset strain of cracking in the film. X-ray stress analyses of the annealed ITO films and thermal mechanical analyses of the PET substrates also clarifies that the residual compressive stress in the ITO film is enhanced with increasing the annealing temperature due to the considerably larger shrinkage of the PET substrate. - Highlights: • Indium-tin oxide (ITO) films were deposited on polyethylene terephthalate (PET). • Mechanical durability of the ITO is improved by high temperature post-annealing. • The shrinkage in the PET increases with rising the post-annealing temperature. • The shrinkage of the PET enhances the compressive stress in the ITO film. • Large compressive stress in the ITO film may improve its mechanical durability

  3. Enzymatic Degradation of Poly(ethylene 2,5-furanoate Powders and Amorphous Films

    Directory of Open Access Journals (Sweden)

    Simone Weinberger

    2017-10-01

    Full Text Available Poly(ethylene 2,5-furanoate (PEF is arousing great interest as a biobased alternative to plastics like poly(ethylene terephthalate (PET due to its wide range of potential applications, such as food and beverage packaging, clothing, and in the car industry. In the present study, the hydrolysis of PEF powders of different molecular masses (Mn = 55, Mw = 104 kg/mol and Mn = 18, Mw = 29 kg/mol and various particle sizes (180 < d and 180 < d < 425 µm using cutinase 1 from Thermobifida cellulosilytica (Thc_cut1 was studied. Thereby, the effects of molecular mass, particle size and crystallinity on enzymatic hydrolysis were investigated. The results show that particles with lower molecular mass are hydrolyzed faster than those with higher masses, and that the higher the molecular mass, the lower the influence of the particle size on the hydrolysis. Furthermore, cutinases from Humicola insolens (HiC and Thc_cut1 were compared with regard to their hydrolytic activity on amorphous PEF films (measured as release of 2,5-furandicarboxylic acid (FDCA and weight loss in different reaction media (1 M KPO pH 8, 0.1 M Tris-HCl pH 7 and at different temperatures (50 °C and 65 °C. A 100% hydrolysis of the PEF films was achieved after only 72 h of incubation with a HiC in 1 M KPO pH 8 at 65 °C. Moreover, the hydrolysis reaction was monitored by LC/TOF-MS analysis of the released reaction products and by Scanning Electron Microscopy (SEM examination of the polymer surfaces. Enzymatic hydrolysis of PEF with Thc_cut1 and HiC has potential for use in surface functionalization and recycling purposes.

  4. Improved damp heat stability of Ga-Doped ZnO thin film by pretreatment of the polyethylene terephthalate substrate

    Science.gov (United States)

    Kim, B. B.; Seo, S. G.; Lim, Y. S.; Choi, H.-S.; Seo, W.-S.; Park, H.-H.

    2013-09-01

    A study on the damp heat stability of transparent conducting ZnO thin film grown on a polyethylene terephthalate substrate (PET) is reported. By thermal annealing of the PET substrate at 100°C with Ar flow in a vacuum chamber prior to the sputtering growth of Ga-doped ZnO (GZO) thin film, significantly enhanced damp heat stability was achieved at 60°C with a 90% relative humidity. Electrical and structural characterizations of the GZO thin films were carried out and the effects of the pretreatment on the improved damp heat stability are discussed.

  5. Structural colors of the SiO2/polyethyleneimine thin films on poly(ethylene terephthalate) substrates

    International Nuclear Information System (INIS)

    Jia, Yanrong; Zhang, Yun; Zhou, Qiubao; Fan, Qinguo; Shao, Jianzhong

    2014-01-01

    The SiO 2 /polyethyleneimine (PEI) films with structural colors on poly(ethylene terephthalate) (PET) substrates were fabricated by an electrostatic self-assembly method. The morphology of the films was characterized by Scanning Electron Microscopy. The results showed that there was no distinguishable multilayered structure found of SiO 2 /PEI films. The optical behaviors of the films were investigated through the color photos captured by a digital camera and the color measurement by a multi-angle spectrophotometer. Different hue and brightness were observed at various viewing angles. The structural colors were dependent on the SiO 2 particle size and the number of assembly cycles. The mechanism of the structural colors generated from the assembled films was elucidated. The morphological structures and the optical properties proved that the SiO 2 /PEI film fabricated on PET substrate formed a homogeneous inorganic/organic SiO 2 /PEI composite layer, and the structural colors were originated from single thin film interference. - Highlights: • SiO 2 /PEI thin films were electrostatic self-assembled on PET substrates. • The surface morphology and optical behavior of the film were investigated. • The structural colors varied with various SiO 2 particle sizes and assembly cycles. • Different hue and lightness of SiO 2 /PEI film were observed at various viewing angles. • Structural color of the SiO 2 /PEI film originated from single thin film interference

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

    International Nuclear Information System (INIS)

    Dorantes R, G.L.

    1997-01-01

    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)

  7. Physical and biological treatments of polyethylene-rice starch plastic films

    Energy Technology Data Exchange (ETDEWEB)

    El-Naggar, Manal M.A., E-mail: mmelnaggar@yahoo.com [Microbiology Lab., National Institute of Oceanography and Fisheries, Alexandria (Egypt); Farag, Magdy Gh. [Development Plastic Center, Victoria, Alexandria (Egypt)

    2010-04-15

    This study aimed to produce an industrial applicable thermo-stable {alpha}-amylase from marine Bacillus amyloliquefaciens which isolated and selected according to its significant enzyme production. The effect of different pH values and temperatures on the bacterial growth and the enzyme production was estimated using an experimental statistical design; maximum amylase production and bacterial growth was obtained at pH 7.0 and 50 deg. C. Some biodegradable polyethylene rice starch plastic films (PERS-P) were manufactured using 0, 2.5, 5, 7.5 and 10% starch concentrations. The biodegradability (reduction in the plastic elongation%) was tested using the exposure to UV radiation at {lambda}{sub 300-400nm} (intensity of about 1000 W/m{sup 2}) and the produced B. amyloliquefaciens thermo-stable {alpha}-amylase. A significant reduction in the elongation% of these biodegradable plastics was observed in both cases especially on testing the 10% PERS-P; they showed a reduction of 26% and 20%, respectively, compared to the untreated plastic films (180 {+-} 5).

  8. Physical and biological treatments of polyethylene-rice starch plastic films

    International Nuclear Information System (INIS)

    El-Naggar, Manal M.A.; Farag, Magdy Gh.

    2010-01-01

    This study aimed to produce an industrial applicable thermo-stable α-amylase from marine Bacillus amyloliquefaciens which isolated and selected according to its significant enzyme production. The effect of different pH values and temperatures on the bacterial growth and the enzyme production was estimated using an experimental statistical design; maximum amylase production and bacterial growth was obtained at pH 7.0 and 50 deg. C. Some biodegradable polyethylene rice starch plastic films (PERS-P) were manufactured using 0, 2.5, 5, 7.5 and 10% starch concentrations. The biodegradability (reduction in the plastic elongation%) was tested using the exposure to UV radiation at λ 300-400nm (intensity of about 1000 W/m 2 ) and the produced B. amyloliquefaciens thermo-stable α-amylase. A significant reduction in the elongation% of these biodegradable plastics was observed in both cases especially on testing the 10% PERS-P; they showed a reduction of 26% and 20%, respectively, compared to the untreated plastic films (180 ± 5).

  9. Surface treatment of polyethylene terephthalate film using atmospheric pressure glow discharge in air

    International Nuclear Information System (INIS)

    Fang Zhi; Qiu Yuchang; Wang Hui

    2004-01-01

    Non-thermal plasmas under atmospheric pressure are of great interest in polymer surface processing because of their convenience, effectiveness and low cost. In this paper, the treatment of Polyethylene terephthalate (PET) film surface for improving hydrophilicity using the non-thermal plasma generated by atmospheric pressure glow discharge (APGD) in air is conducted. The discharge characteristics of APGD are shown by measurement of their electrical discharge parameters and observation of light-emission phenomena, and the surface properties of PET before and after the APGD treatment are studied using contact angle measurement, x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). It is found that the APGD is homogeneous and stable in the whole gas gap, which differs from the commonly filamentary dielectric barrier discharge (DBD). A short time (several seconds) APGD treatment can modify the surface characteristics of PET film markedly and uniformly. After 10 s APGD treatment, the surface oxygen content of PET surface increases to 39%, and the water contact angle decreases to 19 degree, respectively. (authors)

  10. Molded ultra-low density microcellular foams

    International Nuclear Information System (INIS)

    Rand, P.B.; Montoya, O.J.

    1986-07-01

    Ultra-low density (< 0.01 g/cc) microcellular foams were required for the NARYA pulsed-power-driven x-ray laser development program. Because of their extreme fragility, molded pieces would be necessary to successfully field these foams in the pulsed power accelerator. All of the foams evaluated were made by the thermally induced phase separation technique from solutions of water soluble polymers. The process involved rapidly freezing the solution to induce the phase separation, and then freeze drying to remove the water without destroying the foam's structure. More than sixty water soluble polymers were evaluated by attempting to make their solutions into foams. The foams were evaluated for shrinkage, density, and microstructure to determine their suitability for molding and meeting the required density and cell size requirements of 5.0 mg/cc and less than twenty μmeters. Several promising water soluble polymers were identified including the polyactylic acids, guar gums, polyactylamide, and polyethylene oxide. Because of thier purity, structure, and low shrinkage, the polyacrylic acids were chosen to develop molding processes. The initial requirements were for 2.0 cm. long molded rods with diameters of 1.0, 2.0. and 3.0 mm. These rods were made by freezing the solution in thin walled silicon rubber molds, extracting the frozen preform from the mold, and then freeze drying. Requirements for half rods and half annuli necessitated using aluminum molds. Again we successfully molded these shapes. Our best efforts to date involve molding annuli with 3.0 mm outside diameters and 2.0 mm inside diameters

  11. High fluence deposition of polyethylene glycol films at 1064 nm by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Kingshott, P.

    2007-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) has been applied for deposition of thin polyethylene glycol (PEG) films with infrared laser light at 1064 nm. We have irradiated frozen targets (of 1 wt.% PEG dissolved in water) and measured the deposition rate in situ with a quartz crystal 2...... microbalance. The laser fluence needed to produce PEG films turned out to be unexpectedly high with a threshold of 9 J/cm(2) and the deposition rate was much lower than that with laser light at 355 nm. Results from matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI......-TOF-MS) analysis demonstrate that the chemistry, molecular weight and polydispersity of the PEG films were identical to the starting material. Studies of the film surface with scanning electron microscopy (SEM) indicate that the Si-substrate is covered by a relatively homogenous PEG film with few bare spots. (c...

  12. Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds.

    Science.gov (United States)

    Ahmad, Nor Monica; Abdullah, Jaafar; Yusof, Nor Azah; Ab Rashid, Ahmad Hazri; Abd Rahman, Samsulida; Hasan, Md Rakibul

    2016-06-29

    A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075-10 µM and 10-55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days.

  13. Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Nor Monica Ahmad

    2016-06-01

    Full Text Available A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB, polyethylene glycol (PEG, and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE. Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM, Electrochemical Impedance Spectroscopy (EIS, and Cyclic voltamogram (CV. The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075–10 µM and 10–55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days.

  14. Thermal and rheological properties of L-polylactide/polyethylene glycol/silicate nanocomposites films.

    Science.gov (United States)

    Ahmed, Jasim; Varshney, Sunil K; Auras, Rafael; Hwang, Sung W

    2010-10-01

    The melt rheology and thermal properties of polylactide (PLA)-based nanocomposite films that were prepared by solvent casting method with L-PLA, polyethylene glycol (PEG), and montmorillonite clay were studied. The neat PLA showed predominantly solid-like behavior (G' > G″) and the complex viscosity (η*) decreased systematically as the temperature increased from 184 to 196 °C. The elastic modulus (G') of PLA/clay blend showed a significant improvement in the magnitude in the melt, while clay concentration was at 6% wt or higher. At similar condition, PEG dramatically reduced dynamic modulii and complex viscosity of PLA/PEG blend as function of concentration. A nanocomposite blend of PLA/PEG/clay (74/20/6) when compared to the neat polymer and PLA/PEG blend exhibited intermediate values of elastic modulus (G') and complex viscosity (η*) with excellent flexibility. Thermal analysis of different clay loading blends indicated that the melting temperature (T(m)) and glass transition temperature (T(g)) remained unaffected irrespective of clay concentration due to immobilization of polymer chain in the clay nanocomposite. PEG incorporation reduced the T(g) and the T(m) of the blends (PLA/PEG and PLA/PEG/clay) significantly, however, crystallinity increased in the similar condition. The transmission electron microscopy (TEM) image of nanocomposite films indicated good compatibility between PLA and PEG, whereas clay was not thoroughly distributed in the PLA matrix and remained as clusters. The percent crystallinity obtained by X-ray was significantly higher than that of differential scanning calorimeter (DSC) data for PLA.

  15. Rheological and mechanical properties of recycled polyethylene films contaminated by biopolymer.

    Science.gov (United States)

    Gere, D; Czigany, T

    2018-06-01

    Nowadays, with the increasing amount of biopolymers used, it can be expected that biodegradable polymers (e.g. PLA, PBAT) may appear in the petrol-based polymer waste stream. However, their impact on the recycling processes is not known yet; moreover, the properties of the products made from contaminated polymer blends are not easily predictable. Therefore, our goal was to investigate the rheological and mechanical properties of synthetic and biopolymer compounds. We made different compounds from regranulates of mixed polyethylene film waste and original polylactic acid (PLA) by extruison, and injection molded specimens from the compounds. We investigated the rheological properties of the regranulates, and the mechanical properties of the samples. When PLA was added, the viscosity and specific volume of all the blends decreased, and mechanical properties (tensile strength, modulus, and impact strength) changed significantly. Young's modulus increased, while elongation at break and impact strength decreased with the increase of the weight fraction of PLA. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Enhanced electrochromic properties of TiO2 nanoporous film prepared based on an assistance of polyethylene glycol

    Science.gov (United States)

    Xu, Shunjian; Luo, Xiaorui; Xiao, Zonghu; Luo, Yongping; Zhong, Wei; Ou, Hui; Li, Yinshuai

    2017-01-01

    Polyethylene glycol (PEG) was employed as pore-forming agent to prepare TiO2 nanoporous film based on spin-coating a TiO2 nanoparticle mixed paste on fluorine doped tin oxide (FTO) glass. The electrochromic and optical properties of the obtained TiO2 film were investigated by cyclic voltammetry (CV), chronoamperometry (CA) and UV-Vis spectrophotometer. The results show that the PEG in the mixed paste endows the TiO2 film with well-developed porous structure and improves the uniformity of the TiO2 film, which are helpful for the rapid intercalation and extraction of lithium ions within the TiO2 film and the strengthening of the diffuse reflection of visible light in the TiO2 film. As a result, the TiO2 film derived from the mixed paste with PEG displays higher electrochemical activity and more excellent electrochromic performances compared with the TiO2 film derived from the mixed paste without PEG. The switching times of coloration/bleaching are respectively 10.16/5.65 and 12.77/6.13 s for the TiO2 films with PEG and without PEG. The maximum value of the optical contrast of the TiO2 film with PEG is 21.2% while that of the optical contrast of the TiO2 film without PEG is 14.9%. Furthermore, the TiO2 film with PEG has better stability of the colored state than the TiO2 film without PEG.

  17. Preparation of reinforced poly(ethylene oxide) blend hydrogel films containing a drug and assessment of their properties

    International Nuclear Information System (INIS)

    Yang Zhanshan; Zhu Nankang; Yang Shuqin

    1999-01-01

    Reinforced poly(ethylene oxide) blend hydrogen films containing mafenide acetate were prepared by using two freezing-thawing cycles and the irradiation crosslinking technique, and their properties and the drug release were assessed. The results showed that the tensile strength of the reinforced PEO blend hydrogel films increased significantly (p < 0.01), the gel fraction and the elongation at break of the films increased slightly as compared with those formed by the irradiation without the freezing-thawing treatment, indicating that the mechanical properties of the PEO blend hydrogel films can be improved by the freezing-thawing cycles. The reinforced films possessed an ideal flexibility, crosslinking density and elasticity as wound dressings. Swelling studies showed that the equilibrium water content of the hydrogel films expressed in the degree of swelling decreased significantly (p < 0.01), suggesting that a significant structural rearrangement of the films occurred during the freezing process. The structural densification resulted in the increase of the mechanical strength of the hydrogel films. The hydrogels formed by the irradiation at doses of 40 kGy were comparatively stronger. Release studies were run on the reinforced hydrogels with mafenide acetate which was incorporated before the freezing-thawing treatment. Release was followed over seven days. The drug transport was controlled by a regular diffusion model

  18. Evaluación de las propiedades mecánicas de una mezcla densa en caliente modificada con un desecho de polietileno de baja densidad (PEBD Mechanical properties evaluation of a dense hot asphalt mixture modified with a residue of low density polyethylene (LDPE

    Directory of Open Access Journals (Sweden)

    Hugo Rondón Quintana

    2010-04-01

    Full Text Available El artículo presenta los resultados experimentales de ensayar una mezcla asfáltica densa en caliente tipo MDC-2 (acorde con las especificaciones del Instituto Nacional de Vías - INVIAS, 2007 modificada con un desecho de polietileno de baja densidad (PEBD. Para la evaluación del comportamiento de las mezclas asfálticas convencionales (sin aditivo y modificadas se realizaron ensayos Marshall, módulo dinámico, deformación permanente y resistencia a fatiga. Las mezclas fueron elaboradas con un cemento asfáltico (CA producido en Colombia tipo CA 80-100. Al CA con y sin aditivo se realizaron ensayos de caracterización de asfaltos como penetración y punto de ablandamiento. La modificación de las mezclas se realizó por vía húmeda. Las mezclas modificadas con desecho de PEBD experimentan mayor rigidez (bajo carga monotónica y cíclica y resistencia a la deformación permanente en comparación con las convencionales. Sin embargo la resistencia a fatiga de las mezclas convencionales disminuye cuando se adiciona PEBD al CA. Adicionalmente el CA modificado presenta mayor resistencia a la penetración, mayor punto de ablandamiento y menor susceptibilidad térmica a fluir que el convencional.Laboratory tests were used to evaluate the effect on the mechanical properties of a hot asphalt mix (MDC-2 as per INVIAS, 2007 specifications due to the addition by wet way of a residue of low density polyethylene (LDPE. The strength under monotonic load, resilient modulus, rutting and fatigue strength were evaluated. Asphalt cement (AC AC 80-100 was used from Colombia. The results show that the monotonic and cyclic mechanical strength evaluated were higher for the mixes modified with LDPE compared with mixtures with asphalts without additives. However, the mixes modified with LDPE undergo less fatigue strength. Additionally, characterization tests were conducted on asphalt cement with and without additive. The LDPE produces higher penetration resistance

  19. Characterization of Tifton 85 bermudagrass haylage with different layers of polyethylene film and storage time.

    Science.gov (United States)

    Nath, Caroline Daiane; Neres, Marcela Abbado; Scheidt, Kácia Carine; Bersot, Luciano Dos Santos; Sunahara, Samantha Mariana Monteiro; Sarto, Jaqueline Rocha Wobeto; Stangarlin, José Renato; Gomes, Simone Damasceno; Sereno, Mallu Jagnow; Perin, Ana Paula

    2018-03-02

    The objective was to characterize the fermentative and microbiological profile of Tifton 85 bermudagrass haylage with different layers of polyethylene film and storage time. The experimental design consisted of a randomized block design with four and six wrapping layers (100 and 150 microns in total. respectively) allocated in the main plots, through repeated measures analysis (30, 60, and 90 days of storage) with four replicates. The storage time and number of wrapping layers did not show changes in the population of Clostridium and lactic acid bacteria. A decrease was observed in the enterobacteria population with an increase in the storage period in the two wrapping layers studied. Upon opening of the haylage at 30 days, the population of Bacillus was lower in haylages made with six layers of wrapping (3.63 log colony forming units (CFU) g-1). No growth of Listeria sp. or Salmonella sp. was observed during the experimental period. The fungal genera with greater occurrence were Penicillium sp. and Fusarium sp. The following mycotoxins were not detected: ochratoxin A, fumonisins, and zearalenone. Relative to the organic butyric, propionic, and acetic acids, the haylages presented a low concentration of lactic acid; this may have prevented a drop in the pH, which was high when the silos were opened (5.4). The levels of ammoniacal nitrogen and soluble carbohydrates presented no variation among the number of wrapping layers, with an overall average of 35.55 and 38.04 g kg-1. Tifton 85 bermudagrass haylage wrapped with four and six layers presented adequate fermentation and microbiological characteristics in the evaluated periods.

  20. A Study of the Deformation, Network, and Aging of Polyethylene Oxide Films by Infrared Spectroscopy and Calorimetric Measurements

    Directory of Open Access Journals (Sweden)

    Carl Bergeron

    2012-01-01

    Full Text Available The calorimetric and infrared (IR spectroscopy measurements of polyethylene oxide (PEO are used to evaluate the deformation and relaxation that films experience during a temperature cycle (30°C–90°C–30°C. After melting, the intensity of some bands decreases by 10 to 70%. During the temperature cycle, the C–O band in the 1100 cm−1 region and the C–C–O deformation bands at 650 and 500 cm−1 show some new features. A network of cooperative oxygen-hydrogen interactions between the PEO chains form in films with special history, namely, in thermally treated films, in thin films prepared from gel forming solutions, and in thick films after aging. The interchain interaction network is suggested from the IR absorption bands in the 1200 and 900 cm−1 region and also from small bands at 1144 and 956 cm−1. The network seems absent or reduced in thin films. IR spectroscopy appears a sensitive technique to study chain conformations in PEO films and in other materials where order, disorder, and the formation of intermolecular interactions coexist.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Honglong [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Lu; Li, Rong [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Pang, Lijuan [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Jiangtao; Wang, Mouhua [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Wu, Guozhong, E-mail: wuguozhong@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2016-09-30

    Highlights: • Hydrophilic UHMWPE powder and film were obtained by γ-ray pre-irradiation grafting of AA. • A low concentration of AA solution was used for surface modification of UHMWPE. • A small grafting yield of AA sufficiently improved hydrophilicity of UHMWPE powder and film. - Abstract: 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.

  2. Biodegradable and biocompatible poly(ethylene glycol)-based hydrogel films for the regeneration of corneal endothelium.

    Science.gov (United States)

    Ozcelik, Berkay; Brown, Karl D; Blencowe, Anton; Ladewig, Katharina; Stevens, Geoffrey W; Scheerlinck, Jean-Pierre Y; Abberton, Keren; Daniell, Mark; Qiao, Greg G

    2014-09-01

    Corneal endothelial cells (CECs) are responsible for maintaining the transparency of the human cornea. Loss of CECs results in blindness, requiring corneal transplantation. In this study, fabrication of biocompatible and biodegradable poly(ethylene glycol) (PEG)-based hydrogel films (PHFs) for the regeneration and transplantation of CECs is described. The 50-μm thin hydrogel films have similar or greater tensile strengths to human corneal tissue. Light transmission studies reveal that the films are >98% optically transparent, while in vitro degradation studies demonstrate their biodegradation characteristics. Cell culture studies demonstrate the regeneration of sheep corneal endothelium on the PHFs. Although sheep CECs do not regenerate in vivo, these cells proliferate on the films with natural morphology and become 100% confluent within 7 d. Implantation of the PHFs into live sheep corneas demonstrates the robustness of the films for surgical purposes. Regular slit lamp examinations and histology of the cornea after 28 d following surgery reveal minimal inflammatory responses and no toxicity, indicating that the films are benign. The results of this study suggest that PHFs are excellent candidates as platforms for the regeneration and transplantation of CECs as a result of their favorable biocompatibility, degradability, mechanical, and optical properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Low Pressure DC Glow Discharge Air Plasma Surface Treatment of Polyethylene (PE) Film for Improvement of Adhesive Properties

    International Nuclear Information System (INIS)

    Pandiyaraj, Krishnasamy Navaneetha; Yoganand, Paramasivam; Selvarajan, Vengatasamy; Deshmukh, Rajendrasing R.; Balasubramanian, Suresh; Maruthamuthu, Sundaram

    2013-01-01

    The present work deals with the change in surface properties of polyethylene (PE) film using DC low pressure glow discharge air plasma and makes it useful for technical applications. The change in hydrophilicity of the modified PE film surface was investigated by measuring contact angle and surface energy as a function of exposure time. Changes in the morphological and chemical composition of PE films were analyzed by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The improvement in adhesion was studied by measuring T-peel and lap-shear strength. The results show that the wettability and surface energy of the PE film has been improved due to the introduction of oxygen-containing polar groups and an increase in surface roughness. The XPS result clearly shows the increase in concentration of oxygen content and the formation of polar groups on the polymer surface. The AFM observation on PE film shows that the roughness of the surface increased due to plasma treatment. The above morphological and chemical changes enhanced the adhesive properties of the PE film surfaces, which was confirmed by T-peel and lap-shear tests.

  4. Stepwise crystallization and the layered distribution in crystallization kinetics of ultra-thin poly(ethylene terephthalate) film

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Biao, E-mail: chemizuo@zstu.edu.cn, E-mail: wxinping@yahoo.com; Xu, Jianquan; Sun, Shuzheng; Liu, Yue; Yang, Juping; Zhang, Li; Wang, Xinping, E-mail: chemizuo@zstu.edu.cn, E-mail: wxinping@yahoo.com [Department of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of the Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2016-06-21

    Crystallization is an important property of polymeric materials. In conventional viewpoint, the transformation of disordered chains into crystals is usually a spatially homogeneous process (i.e., it occurs simultaneously throughout the sample), that is, the crystallization rate at each local position within the sample is almost the same. Here, we show that crystallization of ultra-thin poly(ethylene terephthalate) (PET) films can occur in the heterogeneous way, exhibiting a stepwise crystallization process. We found that the layered distribution of glass transition dynamics of thin film modifies the corresponding crystallization behavior, giving rise to the layered distribution of the crystallization kinetics of PET films, with an 11-nm-thick surface layer having faster crystallization rate and the underlying layer showing bulk-like behavior. The layered distribution in crystallization kinetics results in a particular stepwise crystallization behavior during heating the sample, with the two cold-crystallization temperatures separated by up to 20 K. Meanwhile, interfacial interaction is crucial for the occurrence of the heterogeneous crystallization, as the thin film crystallizes simultaneously if the interfacial interaction is relatively strong. We anticipate that this mechanism of stepwise crystallization of thin polymeric films will allow new insight into the chain organization in confined environments and permit independent manipulation of localized properties of nanomaterials.

  5. Magnetron sputtered transparent conductive zinc-oxide stabilized amorphous indium oxide thin films on polyethylene terephthalate substrates at ambient temperature

    International Nuclear Information System (INIS)

    Yan, Y.; Zhang, X.-F.; Ding, Y.-T.

    2013-01-01

    Amorphous transparent conducting zinc-oxide stabilized indium oxide thin films, named amorphous indium zinc oxide (a-IZO), were deposited by direct current magnetron sputtering at ambient temperature on flexible polyethylene terephthalate substrates. It has been demonstrated that the electrical resistivity could attain as low as ∼ 5 × 10 −4 Ω cm, which was noticeably lower than amorphous indium tin oxide films prepared at the same condition, while the visible transmittance exceeded 84% with the refractive index of 1.85–2.00. In our experiments, introduction of oxygen gas appeared to be beneficial to the improvement of the transparency and electrical conductivity. Both free carrier absorption and indirect transition were observed and Burstein–Moss effect proved a-IZO to be a degenerated amorphous semiconductor. However, the linear relation between the optical band gap and the band tail width which usually observed in covalent amorphous semiconductor such as a-Si:H was not conserved. Besides, porosity could greatly determine the resistivity and optical constants for the thickness variation at this deposition condition. Furthermore, a broad photoluminescence peak around 510 nm was identified when more than 1.5 sccm oxygen was introduced. - Highlights: ► Highly conducting amorphous zinc-oxide stabilized indium oxide thin films were prepared. ► The films were fabricated on polyethylene terephthalate at ambient temperature. ► Introduction of oxygen can improve the transparency and electrical conductivity. ► The linear relation between optical band gap and band tail width was not conserved

  6. Iridescent cellulose nanocrystal/polyethylene oxide composite films with low coefficient of thermal expansion

    Science.gov (United States)

    Jairo A. Diaz; Julia L. Braun; Robert J. Moon; Jeffrey P. Youngblood

    2015-01-01

    Simultaneous control over optical and thermal properties is particularly challenging and highly desired in fields like organic electronics. Here we incorporated cellulose nanocrystals (CNCs) into polyethylene oxide (PEO) in an attempt to preserve the iridescent CNC optical reflection given by their chiral nematic organisation, while reducing the composite thermal...

  7. A Rapid Method for Deposition of Sn-Doped GaN Thin Films on Glass and Polyethylene Terephthalate Substrates

    Science.gov (United States)

    Pat, Suat; Özen, Soner; Korkmaz, Şadan

    2018-01-01

    We report the influence of Sn doping on microstructure, surface, and optical properties of GaN thin films deposited on glass and polyethylene terephthalate (PET) substrate. Sn-doped GaN thin films have been deposited by thermionic vacuum arc (TVA) at low temperature. TVA is a rapid deposition technology for thin film growth. Surface and optical properties of the thin films were presented. Grain size, height distribution, roughness values were determined. Grain sizes were calculated as 20 nm and 13 nm for glass and PET substrates, respectively. Nano crystalline forms were shown by field emission scanning electron microscopy. Optical band gap values were determined by optical methods and photoluminescence measurement. The optical band gap values of Sn doped GaN on glass and PET were determined to be approximately ˜3.40 eV and ˜3.47 eV, respectively. As a result, TVA is a rapid and low temperature deposition technology for the Sn doped GaN deposited on glass and PET substrate.

  8. Surface chemical structure of poly(ethylene naphthalate) films during degradation in low-pressure high-frequency plasma treatments

    Science.gov (United States)

    Kamata, Noritsugu; Yuji, Toshifumi; Thungsuk, Nuttee; Arunrungrusmi, Somchai; Chansri, Pakpoom; Kinoshita, Hiroyuki; Mungkung, Narong

    2018-06-01

    The surface chemical structure of poly(ethylene naphthalate) (PEN) films treated with a low-pressure, high-frequency plasma was investigated by storing in a box at room temperature to protect the PEN film surface from dust. The functional groups on the PEN film surface changed over time. The functional groups of –C=O, –COH, and –COOH were abundant in the Ar + O2 mixture gas plasma-treated PEN samples as compared with those in untreated PEN samples. The changes occurred rapidly after 2 d following the plasma treatment, reaching steady states 8 d after the treatment. Hydrophobicity had an inverse relationship with the concentration of these functional groups on the surface. Thus, the effect of the low-pressure high-frequency plasma treatment on PEN varies as a function of storage time. This means that radical oxygen and oxygen molecules are clearly generated in the plasma, and this is one index to confirm that radical reaction has definitely occurred between the gas and the PEN film surface with a low-pressure high-frequency plasma.

  9. Effects of L-arginine immobilization on the anticoagulant activity and hemolytic property of polyethylene terephthalate films

    International Nuclear Information System (INIS)

    Liu Yun; Yang Yun; Wu Feng

    2010-01-01

    Surface modification of polyethylene terephthalate (PET) films was performed with L-arginine (L-Arg) to gain an improved anticoagulant surface. The surface chemistry changes of modified films were characterized by X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The in vitro anticoagulant activities of the surface-modified PET films were evaluated by blood clotting test, hemolytic test, and the measurement of clotting time including plasma recalcification time (PRT), activated partial thromboplastin time (APTT), and prothrombin time (PT). The data of blood coagulation index (BCI) for L-arginine modified PET films (PET-Arg) was larger than that for PET at the same blood-sample contact time. The hemolysis ratio for PET-Arg was less than that for PET and within the accepted standard for biomaterials. The PRT and APTT for PET-Arg were significantly prolonged by 189 s and 25 s, respectively, compared to those for the unmodified PET. All results suggested that the currently described modification method could be a possible candidate to create antithrombogenic PET surfaces which would be useful for further medical applications.

  10. Efficient Inorganic Perovskite Light-Emitting Diodes with Polyethylene Glycol Passivated Ultrathin CsPbBr3 Films.

    Science.gov (United States)

    Song, Li; Guo, Xiaoyang; Hu, Yongsheng; Lv, Ying; Lin, Jie; Liu, Zheqin; Fan, Yi; Liu, Xingyuan

    2017-09-07

    Efficient inorganic perovskite light-emitting diodes (PeLEDs) with an ultrathin perovskite emission layer (∼30 nm) were realized by doping Lewis base polyethylene glycol (PEG) into CsPbBr 3 films. PEG in the perovskite films not only physically fills the crystal boundaries but also interacts with the perovskite crystals to passivate the crystal grains, reduce nonradiative recombination, and ensure efficient luminance and high efficiency. As a result, promoted brightness, current efficiency (CE), and external quantum efficiency (EQE) were achieved. The nonradiative decay rate of the PEG:CsPbBr 3 composite film is 1 order of magnitude less than that of the neat CsPbBr 3 film. After further optimization of the molar ratio between CsBr and PbBr 2 , a peak CE of 19 cd/A, a maximum EQE of 5.34%, and a maximum brightness of 36600 cd/m 2 were achieved, demonstrating the interaction between PEG and the precursors. The results are expected to offer some helpful implications in optimizing the polymer-assisted PeLEDs with ultrathin emission layers, which might have potential application in see-through displays.

  11. 76 FR 13128 - Polyethylene Terephthalate Film, Sheet, and Strip (PET Film) From Taiwan: Extension of Time Limit...

    Science.gov (United States)

    2011-03-10

    ... Film, Sheet, and Strip (PET Film) From Taiwan: Extension of Time Limit for the Preliminary Results of...: Emily Halle or Gene Calvert, AD/CVD Operations, Office 6, Import Administration, International Trade... antidumping duty order on PET Film from Taiwan covering the period July 1, 2009, through June 30, 2010. See...

  12. 77 FR 18206 - Polyethylene Terephthalate Film, Sheet, and Strip (PET Film) From Taiwan: Extension of Time Limit...

    Science.gov (United States)

    2012-03-27

    ... Film, Sheet, and Strip (PET Film) From Taiwan: Extension of Time Limit for the Preliminary Results of...: Gene Calvert or Jun Jack Zhao, AD/CVD Operations, Office 6, Import Administration, International Trade... the antidumping duty order on PET Film from Taiwan covering the period July 1, 2010 through June 30...

  13. Sampling low-density gypsy moth populations

    Science.gov (United States)

    William E. Wallner; Clive G. Jones; Joseph S. Elkinton; Bruce L. Parker

    1991-01-01

    The techniques and methodology for sampling gypsy moth, Lymantria dispar L., at low densities, less than 100 egg masses/ha (EM/ha), are compared. Forest managers have constraints of time and cost, and need a useful, simple predictable means to assist them in sampling gypsy moth populations. A comparison of various techniques coupled with results of...

  14. 78 FR 47276 - Polyethylene Terephthalate (PET) Film, Sheet, and Strip From India: Final Results of the...

    Science.gov (United States)

    2013-08-05

    ... (PET) Film, Sheet, and Strip From India: Final Results of the Expedited Second Sunset Review of the... terephthalate (PET) film, sheet, and strip (``PET film'') from India. The Department finds that revocation of... INFORMATION CONTACT: Sean Carey or Dana Mermelstein, AD/CVD Operations, Office 6, Import Administration...

  15. 76 FR 71512 - Polyethylene Terephthalate Film, Sheet, and Strip From Korea: Final Results of Antidumping Duty...

    Science.gov (United States)

    2011-11-18

    ... terephthalate film, sheet, and strip (PET film) from Korea, covering the June 1, 2009, to May 31, 2010, period... the preliminary results. In addition, the Department is revoking the antidumping order on PET film... CONTACT: Tyler Weinhold or Robert James, AD/CVD Operations, Office 7, Import Administration, International...

  16. 75 FR 49893 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China...

    Science.gov (United States)

    2010-08-16

    ..., Stretch Wrap Film, Plastic Bag, Paper Plate, PE Foam using November 2008 through October 2009 weighted... Teijin Films, Mitsubishi Polyester Film, Inc., SKC, Inc., and Toray Plastics (America), Inc.... U.S. Price In accordance with section 772(a) of the Act, the Department used EP as the basis for U.S...

  17. Understanding of electrochemical and structural changes of polypyrrole/polyethylene glycol composite films in aqueous solution

    International Nuclear Information System (INIS)

    Pirvu, Cristian; Manole, Claudiu Constantin; Stoian, Andrei Bogdan; Demetrescu, Ioana

    2011-01-01

    Highlights: → Electrochemical monitoring of PPy and PPy-PEG films over immersion time. → Electrochemical and surface analysis showed that PEG improves the stability of PPy films. → Mott-Schottky analysis reveals p-type conductance for both films. → In situ AFM analysis sustains electrochemical behaviour. → A model of PPy and PPy-PEG films behaviour during immersion was elaborated. - Abstract: Electrochemical monitoring of electrical and structural changes of both PPy and PPy-PEG films electrochemical deposited, in order to highlight if the structural stability offered by PEG has an influence on electrical properties and stability in aqueous solution over immersion time was investigated. Electrochemical analysis suggests that PPy-PEG film inserts cations easier than PPy film for a short immersion time probably due to ability of PEG to form complexes with metal cations. The FTIR spectra showed that the PEG incorporation decreases the rate of PPy overoxidation probably by restraining the electron release and by rendering O 2 inaccessible to PPy. Mott-Schottky analysis based on capacitance measurement reveal p-type conductance for both films. The in situ AFM analysis sustains electrochemical behaviour and has permitted elaboration of a model of PPy and PPy-PEG films behaviour during immersion in testing solution.

  18. Understanding of electrochemical and structural changes of polypyrrole/polyethylene glycol composite films in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Pirvu, Cristian, E-mail: c_pirvu@chim.pub.ro [University Polytechnic of Bucharest, Faculty of Applied Chemistry and Materials Science, 1-7 Polizu, 011061 Bucharest (Romania); Manole, Claudiu Constantin; Stoian, Andrei Bogdan; Demetrescu, Ioana [University Polytechnic of Bucharest, Faculty of Applied Chemistry and Materials Science, 1-7 Polizu, 011061 Bucharest (Romania)

    2011-11-30

    Highlights: > Electrochemical monitoring of PPy and PPy-PEG films over immersion time. > Electrochemical and surface analysis showed that PEG improves the stability of PPy films. > Mott-Schottky analysis reveals p-type conductance for both films. > In situ AFM analysis sustains electrochemical behaviour. > A model of PPy and PPy-PEG films behaviour during immersion was elaborated. - Abstract: Electrochemical monitoring of electrical and structural changes of both PPy and PPy-PEG films electrochemical deposited, in order to highlight if the structural stability offered by PEG has an influence on electrical properties and stability in aqueous solution over immersion time was investigated. Electrochemical analysis suggests that PPy-PEG film inserts cations easier than PPy film for a short immersion time probably due to ability of PEG to form complexes with metal cations. The FTIR spectra showed that the PEG incorporation decreases the rate of PPy overoxidation probably by restraining the electron release and by rendering O{sub 2} inaccessible to PPy. Mott-Schottky analysis based on capacitance measurement reveal p-type conductance for both films. The in situ AFM analysis sustains electrochemical behaviour and has permitted elaboration of a model of PPy and PPy-PEG films behaviour during immersion in testing solution.

  19. Grafting of copolymer styrene maleic anhydride on poly(ethylene terephthalate) film by chemical reaction and by plasma method

    Energy Technology Data Exchange (ETDEWEB)

    Bigan, Muriel; Bigot, Julien [Laboratoire de Chimie Organique et Macromoleculaire (UMR 8009), Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France); Mutel, Brigitte [Laboratoire de Genie des Procedes d' Interactions Fluides reactifs-Materiaux (UPRES-EA 3751), Batiment C5, Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: Brigitte.mutel@univ-lille1.fr; Coqueret, Xavier [Laboratoire Reactions Selectives et Applications (UMR-CNRS 6519) Universite de Reims Champagne-Ardennes, B.P. 1039, 51687 Reims Cedex 2 (France)

    2008-02-15

    This work deals with the chemical grafting of a styrene maleic anhydride copolymer on the surface of a previously hydrolyzed polyethylene terephthalate (PET) film 12 {mu}m thick via covalent bond. Two different ways are studied. The first one involves an activation of the hydrolyzed PET by the triethylamine before the grafting step. In the second one, the copolymer reacts with the 4-dimethylaminopyridine in order to form maleinyl pyridinium salt which reacts with alcohol function of the hydrolyzed PET. Characterization and quantification of the grafting are performed by Fourier transform infrared spectroscopy. Factorial experiment designs are used to optimize the process and to estimate experimental parameters effects. The opportunity to associate the chemical process to a cold remote nitrogen plasma one is also examined.

  20. 75 FR 10758 - Polyethylene Terephthalate Film, Sheet and Strip from India: Initiation of Antidumping Duty and...

    Science.gov (United States)

    2010-03-09

    ..., Sheet and Strip (PET Film) from India. The Department determines that these requests are sufficient to... CONTACT: Elfi Blum or Mark Hoadley, AD/CVD Operations, Office 6, Import Administration, International...: Background The notice announcing the antidumping duty order on PET Film from India was published on July 1...

  1. 76 FR 42113 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Extension...

    Science.gov (United States)

    2011-07-18

    ..., and strip (``PET film'') from the People's Republic of China (``PRC''). This review covers the period... CONTACT: Thomas Martin or Jonathan Hill, AD/CVD Operations, Office 4, Import Administration, International... review of the antidumping duty order on PET film from the PRC. See Initiation of Antidumping and...

  2. 78 FR 45512 - Polyethylene Terephthalate Film from India and Taiwan: Extension of Time Limits for Preliminary...

    Science.gov (United States)

    2013-07-29

    ... or Jacky Arrowsmith at 202-482-1396 or 202-482-5255, respectively, AD/CVD Operations, Office 6... terephthalate film (PET Film) from India and Taiwan, pursuant to section 751(c) of the Tariff Act of 1930, as..., Office of Investigations, International Trade Commission, regarding ``Sunset Reviews Initiated on April 2...

  3. 76 FR 61085 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Extension...

    Science.gov (United States)

    2011-10-03

    ..., and strip (``PET film'') from the People's Republic of China (``PRC''). This review covers the period... CONTACT: Thomas Martin or Jonathan Hill, AD/CVD Operations, Office 4, Import Administration, International... review of the antidumping duty order on PET film from the PRC. See Initiation of Antidumping and...

  4. 76 FR 68140 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China...

    Science.gov (United States)

    2011-11-03

    ... latex. Tracing and drafting film is also excluded. PET film is classifiable under subheading 3920.62.00... from data on the following Web site: http://www.infobanc.com/logistics/logtruck.htm .\\64\\ The logistics section of this Web site contains inland freight truck rates between many large Indian cities. We did not...

  5. 76 FR 9753 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China: Final...

    Science.gov (United States)

    2011-02-22

    ... Records Unit (``CRU''), Main Commerce Building, Room 7046, and is accessible on the Department's Web site... SBR latex. Tracing and drafting film is also excluded. PET film is classifiable under subheading 3920... recertify their separate rates using the separate rate certification provided at the Department's Web site...

  6. POLYETHYLENE ENCAPSULATION

    International Nuclear Information System (INIS)

    Kalb, P.

    2001-01-01

    (NRC, 1991; 1983) Because polyethylene is a relatively new material, it is difficult to predict its long-term durability. However, prior to scale-up of the microencapsulation process, a study was conducted to evaluate potential degradation mechanisms. The study examined potential effects on mechanical integrity from exposure to chemicals and solvents, thermal cycling, saturated environments, microbial attack, and high gamma-radiation fields (Kalb et al., 1991). At ambient temperatures, polyethylene is relatively inert to most chemicals, including organic solvents, acids, and alkaline solutions. Exposure to changes in temperature or saturated soil conditions have been shown to degrade the mechanical integrity of some waste forms, but had little or no measurable impact on polyethylene waste forms. Low-density polyethylene is not susceptible to growth of microbial organisms, a fact that is evidenced by the lack of plastics decomposition in municipal waste landfills. When exposed to gamma-radiation at total doses of up to lo8 rad, additional cross-linking of the polymer occurs, resulting in increased strength and lower leachability

  7. Polyethylene oxide film coating enhances lithium cycling efficiency of an anode-free lithium-metal battery.

    Science.gov (United States)

    Assegie, Addisu Alemayehu; Cheng, Ju-Hsiang; Kuo, Li-Ming; Su, Wei-Nien; Hwang, Bing-Joe

    2018-03-29

    The practical implementation of an anode-free lithium-metal battery with promising high capacity is hampered by dendrite formation and low coulombic efficiency. Most notably, these challenges stem from non-uniform lithium plating and unstable SEI layer formation on the bare copper electrode. Herein, we revealed the homogeneous deposition of lithium and effective suppression of dendrite formation using a copper electrode coated with a polyethylene oxide (PEO) film in an electrolyte comprising 1 M LiTFSI, DME/DOL (1/1, v/v) and 2 wt% LiNO3. More importantly, the PEO film coating promoted the formation of a thin and robust SEI layer film by hosting lithium and regulating the inevitable reaction of lithium with the electrolyte. The modified electrode exhibited stable cycling of lithium with an average coulombic efficiency of ∼100% over 200 cycles and low voltage hysteresis (∼30 mV) at a current density of 0.5 mA cm-2. Moreover, we tested the anode-free battery experimentally by integrating it with an LiFePO4 cathode into a full-cell configuration (Cu@PEO/LiFePO4). The new cell demonstrated stable cycling with an average coulombic efficiency of 98.6% and capacity retention of 30% in the 200th cycle at a rate of 0.2C. These impressive enhancements in cycle life and capacity retention result from the synergy of the PEO film coating, high electrode-electrolyte interface compatibility, stable polar oligomer formation from the reduction of 1,3-dioxolane and the generation of SEI-stabilizing nitrite and nitride upon lithium nitrate reduction. Our result opens up a new route to realize anode-free batteries by modifying the copper anode with PEO to achieve ever more demanding yet safe interfacial chemistry and control of dendrite formation.

  8. Tuning thin-film electrolyte for lithium battery by grafting cyclic carbonate and combed poly(ethylene oxide) on polysiloxane.

    Science.gov (United States)

    Li, Jie; Lin, Yue; Yao, Hehua; Yuan, Changfu; Liu, Jin

    2014-07-01

    A tunable polysiloxane thin-film electrolyte for all-solid-state lithium-ion batteries was developed. The polysiloxane was synthesized by hydrosilylation of polymethylhydrosiloxane with cyclic [(allyloxy)methyl]ethylene ester carbonic acid and vinyl tris(2-methoxyethoxy)silane. (1) H NMR spectroscopy and gel-permeation chromatography demonstrated that the bifunctional groups of the cyclic propylene carbonate (PC) and combed poly(ethylene oxide) (PEO) were well grafted on the polysiloxane. At PC/PEO=6:4, the polysiloxane-based electrolyte had an ionic conductivity of 1.55 × 10(-4) and 1.50 × 10(-3)  S cm(-1) at 25 and 100 °C, respectively. The LiFePO4 /Li batteries fabricated with the thin-film electrolyte presented excellent cycling performance in the temperature range from 25 to 100 °C with an initial discharge capacity at a rate of 1 C of 88.2 and 140 mA h g(-1) at 25 and 100 °C, respectively. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Biodegradation evaluation of recycled polyethylene doped with Moringa oleifera oil

    International Nuclear Information System (INIS)

    Bicalho, Luciana A.; Novack, Katia M.; Melo, Tania M.S.

    2011-01-01

    Chemical modifications and use of additives are some of the mainly ways to obtain polymer materials with especial properties. Vegetable oils incorporated to polymers preserve their structure while make possible a reduction of degradation rate. This work proposed the use of polyethylene, one of the most common polymer commodities, because of its low cost and wide application. In this project it was verified the possibility of making polymer materials with properties of a natural product through the incorporation of Moringa oleifera oil to recycled low density polyethylene (LDPEr) in different proportions. The films were buried for different times and their degradation was evaluated.) Samples were characterized by DSC, TGA and XRD. It was observed that samples doped with Moringa oil showed lower degradation time. (author)

  10. From coffee ring to spherulites ring of poly(ethylene oxide) film from drying droplet

    Science.gov (United States)

    Hu, Yinchun; Zhang, Xuerong; Qiu, Maibo; Wei, Yan; Zhou, Qiong; Huang, Di

    2018-03-01

    We discuss how the "spherulites ring" morphology and "coffee ring" profile of PEO film formed by the drying droplet at glass substrate with different heating rate. Upon increasing the heating rate of substrate, it is found that deposited PEO film from drying droplet shows the unusually observed "coffee ring" profile and "spherulites ring" morphology. The main mechanism for this phenomenon is proposed to be an enhanced Marangoni convection which is induced by the increased solute concentration gradient and reduced viscous force above 70 °C. A simple formation mechanism of the unusually observed "coffee ring" profile and "spherulites ring" morphology is proposed. These findings can be exploited to trace the center of Marangoni convection, with potential applications in designing the spherulite patterns of crystalline polymer films in ink-jet printing and self-assembly fields.

  11. Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

    Science.gov (United States)

    Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

    2015-05-01

    Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers' perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

  12. Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

    Energy Technology Data Exchange (ETDEWEB)

    Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H. [Department of Chemical Engineering, École Polytechnique de Montréal, Montréal, Québec, H3C3A7 (Canada)

    2015-05-22

    Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers’ perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

  13. Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

    International Nuclear Information System (INIS)

    Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

    2015-01-01

    Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers’ perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied

  14. Biodegradability Study of the Blend Film of High Density Polyethylene and Poly(lactic acid Disposable Packages Flake

    Directory of Open Access Journals (Sweden)

    Elahe Baghi Neirizi

    2016-03-01

    Full Text Available One of the major concerns of using a non-biodegradable polymer product is its disposal at the end of its life cycle. Development of biodegradable plastics promises an alternative solution to combat this problem. Blending of poly(lactic acid with non-biodegradable polymers is a practical and economical method for modifying the biodegradability properties of non-biodegradable polymers. In this study, soil biodegradability of the blends of high density polyethylene (HDPE and variable amounts of recycled poly(lactic acid (r-PLA plastic flakes at 0, 5, 10, 20, 30, 40 and 50 wt% was studied. The behavior of the force-elongation profile of the blends having r-PLA content of lower than 30 wt% was approximately the same as that of pure HDPE while, it was completely different for the other blends. Tearing force and elongation-at-yield-point of the blends films with the 20 to 50 wt% r-PLA were decreased significantly after 60 days of soil biodegradability test. Morphological study showed that biodegradability of the blend films at surface of the samples (deep pores and grooves was increased with extended biodegradability time and higher r-PLA content, while, this variation was significant for the blend films of more than 20 wt% r-PLA content. Thermal properties evaluation by differential scanning calorimetry (DSC curves indicated that the glass transition temperature and enthalpy peaks during the heating stage were eliminated with increasing the biodegradability testing time. Also, reduction in the crystallinity degree of the r-PLA component with increasing the biodegradability testing time coincided with the earlier results.

  15. Magnetic properties of thin films obtained by ion implantation of 3d metals in polyethylene-terephthalate

    International Nuclear Information System (INIS)

    Petukhov, V.Yu.; Ibragimova, M.I.; Khabibullina, N.R; Zheglov, E.P.; Muller, R.

    2002-01-01

    Polymer films containing small metal particles have been attracting particular interest because of their unique properties. Implantation of metal ions in polymers is one of the methods to synthesize metal-polymer nano-composite materials. Ion implantation makes possible the magnetic nano-structures with controlled parameters. Previously, we showed that 3d-metal implantation into numerous polymers (polymethylmethacrylate, phosphorus containing polymethylmethacrylate) resulted in the formation of a composite film consisting of metal nanoparticles buried in an implanted layer. The particles are usually found to be distributed randomly in the surface layer. It has been established that structural peculiarities, phase composition, and magnetic properties of synthesized metal-polymer systems depend on the type of the initial polymer matrix, ion types, as well as conditions of ion implantation. In the present study we have been prepared thin metal-polymer composite films by ion-beam implantation of Fe + and Co + ions in polyethylene terephthalate. The implantation of 40 keV ions at room temperature with doses from 2·10 1 6 to 3·10 17 cm -2 have been performed, with the ion current density not exceeding 10 μA/cm 2 . The magnetic properties have been investigated both by ferromagnetic resonance (FMR) and vibrating sample magnetometry (VSM). FMR spectra were recorded using magnetic radio spectrometer Varian E-12 with frequency of 9.5 GHz at room temperature. The dependencies of FMR spectra on orientation have been measured for all samples. Measurements were carried out for two orientations of the sample, normal direction of the films being either parallel or perpendicular to dc magnetic field. The values of the effective magnetization were calculated from orientation dependencies. Thin ferromagnetic films (TFF) have been shown to form for samples with both implanted ions. For samples implanted with Co + ions, the appearance of FMR lines occurs at doses markedly greater

  16. 77 FR 73428 - Polyethylene Terephthalate Film, Sheet, and Strip From the People's Republic of China...

    Science.gov (United States)

    2012-12-10

    .... Because the PRC is a nonmarket economy within the meaning of section 771(18) of the Act, NV has been... China Limited 2.95 Shaoxing Xiangyu Green Packing Co., Ltd 0.00 Fuwei Films (Shandong) Co., Ltd 2.95... the PRC-wide rate.\\9\\ \\9\\ For a full discussion of this practice, see Non-Market Economy Antidumping...

  17. 77 FR 31833 - Polyethylene Terephthalate Film, Sheet, and Strip From Brazil: Notice of Rescission of...

    Science.gov (United States)

    2012-05-30

    ... strip (PET Film) from Brazil for the period November 1, 2010, through October 31, 2011. Based on..., Office 7, Import Administration, International Trade Administration, U.S. Department of Commerce, 14th... Federal Register a notice of initiation of an administrative review of the antidumping duty order on PET...

  18. 77 FR 73010 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates; Preliminary...

    Science.gov (United States)

    2012-12-07

    ... Film, Sheet, and Strip From the United Arab Emirates; Preliminary Results of Antidumping Duty... United Arab Emirates (UAE). The period of review (POR) is November 1, 2010, through October 31, 2011. The... Strip from Brazil, the People's Republic of China and the United Arab Emirates: Antidumping Duty Orders...

  19. 78 FR 48147 - Polyethylene Terephthalate Film, Sheet, and Strip From India: Preliminary Results of...

    Science.gov (United States)

    2013-08-07

    ... resinous or inorganic layer of more than 0.00001 inches thick. Imports of PET film are classifiable in the... limit for filing case briefs.\\3\\ Pursuant to 19 CFR 351.309(d)(2), rebuttal briefs must be limited to...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-01

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

  1. Poly(ethylene glycol) dicarboxylate/poly(ethylene oxide) hydrogel film co-crosslinked by electron beam irradiation as an anti-adhesion barrier

    International Nuclear Information System (INIS)

    Haryanto,; Singh, Deepti; Han, Sung Soo; Son, Jun Hyuk; Kim, Seong Cheol

    2015-01-01

    The cross-linked poly(ethylene glycol) dicarboxylate (PEGDC)/poly(ethylene oxide) (PEO) and poly(ethylene glycol) dimethacrylate (PEGDMA)/(PEO) hydrogels were developed for possible biomedical applications such as an anti-adhesion barrier. Various contents of PEGDC/PEO film were irradiated using an electron beam with various beam intensities in order to obtain various degrees of crosslinked hydrogels. The optimum dose (300 kGy) and total crosslinker content of 10% were used to prepare crosslinked hydrogel films with three different compositions (10% PEGDC, 10% PEGDMA, 5% PEGDC–5% PEGDMA). Among them, 10% PEGDC hydrogel film exhibited the highest elongation at break (69.33 ± 6.87%) with high mechanical strength. 10% PEGDC hydrogel film showed the lowest hemolysis activity (6.03 ± 0.01%) and the highest tissue adherence (75.67 ± 1.15 cN). The result also indicated that the carboxyl groups in PEGDC affect the tissue adherence of hydrogel films via H-bonding interactions. In animal studies, 10% PEGDC anti-adhesion hydrogel film degraded within 3 weeks and demonstrated better anti-adhesive effect compared to Guardix-SG®. - Highlights: • The crosslinked PEGDC/PEO hydrogel was developed by e-beam irradiation. • 10% PEGDC hydrogel film showed the highest elongation at break and tissue adhesion. • The COOH group enhanced the tissue adherence of hydrogel films on the intestine. • 10% PEGDC hydrogel film demonstrated a good anti-adhesive effect in animal study. • All of the hydrogel films with 10% PEGDC degraded in vivo within three weeks

  2. Effects of pre-strain applied at a polyethylene terephthalate substrate before the coating of TiO2 film on the coating film quality and optical performance

    International Nuclear Information System (INIS)

    Li, Tse-Chang; Wu, Bo-Hsiung; Lin, Jen-Fin

    2011-01-01

    A mold was designed to create various strains in polyethylene terephthalate (PET) substrates before the deposition of TiO 2 film to simulate deposition process on a cylindrical drum. The residual stress of the PET substrate with TiO 2 film significantly increased with increasing strain, decreasing the radius of curvature. Compared to the as-received PET substrate, there was a noticeable increase in the surface roughness in the PET/TiO 2 specimens when a large strain was applied. The formation of voids or cavities in the TiO 2 layer significantly increased the roughness of the specimen. The mean cavity size and depth increased with increasing strain. For strains ≤ 4%, the specimen's hardness and Young's modulus factored by the voids/cavities increased with increasing surface roughness. The optical absorption increased with increasing surface roughness before becoming asymptotic to a constant value. The strain applied to the PET substrate before TiO 2 deposition greatly affects the optical reflection, transmittance, and absorption.

  3. The study on grafting comonomer of n-butyl acrylate and styrene onto poly(ethylene terephthalate) film by gamma-ray induced graft copolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Ping Xiang; Wang Mozhen [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ge Xuewu, E-mail: xwge@ustc.edu.c [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2010-09-15

    Poly(ethylene terephthalate) (PET) film was successfully grafted with n-butyl acrylate and styrene comonomer through gamma-ray induced graft copolymerization. The degree of grafting (DG) and the composition of grafted side chain were characterized by {sup 1}H NMR. It was found that St can inhibit the homopolymerization of BA effectively and increase the DG when the concentration of comonomer mixture is kept constant. The proportion of St to BA in grafted side chain has a positive dependence on the feed ratio of St, which ultimately approaches the feed ratio. The thermal properties of poly(ethylene terephthalate)-graft-poly(n-butyl acrylate-co-styrene) (PET-g-P(BA-co-St)) films were investigated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). The T{sub g} of PET decreases with the DG, indicating that the grafted P(BA-co-St) copolymer has good compatibility with PET backbone.

  4. Direct Silver Micro Circuit Patterning on Transparent Polyethylene Terephthalate Film Using Laser-Induced Photothermochemical Synthesis

    Directory of Open Access Journals (Sweden)

    Chen-Jui Lan

    2017-02-01

    Full Text Available This study presents a new and improved approach to the rapid and green fabrication of highly conductive microscale silver structures on low-cost transparent polyethylene terephthalate (PET flexible substrate. In this new laser direct synthesis and pattering (LDSP process, silver microstructures are simultaneously synthesized and laid down in a predetermined pattern using a low power continuous wave (CW laser. The silver ion processing solution, which is transparent and reactive, contains a red azo dye as the absorbing material. The silver pattern is formed by photothermochemical reduction of the silver ions induced by the focused CW laser beam. In this improved LDSP process, the non-toxic additive in the transparent ionic solution absorbs energy from a low cost CW visible laser without the need for the introduction of any hazardous chemical process. Tests were carried out to determine the durability of the conductive patterns, and numerical analyses of the thermal and fluid transport were performed to investigate the morphology of the deposited patterns. This technology is an advanced method for preparing micro-scale circuitry on an inexpensive, flexible, and transparent polymer substrate that is fast, environmentally benign, and shows potential for Roll-to-Roll manufacture.

  5. Influence of temperature on radiation-induced graft polymerization of styrene onto poly(ethylene terephthalate) nuclear membranes and films

    International Nuclear Information System (INIS)

    Zhitaryuk, N.I.; Shtan'ko, N.I.

    1989-01-01

    Temperature effect on kinetics of radiation-induced graft polymerization of styrene onto poly(ethylene terephthalate) (PETP) nuclear membranes with various parameters (pore diameter, the average distance between the pores) as well as onto PETP films with different thickness has been studied. Graft polymerization has been carried out by the methods of preirradiation in air and in vacuum. The overall activation energy of grafting as well as the activation energy of swelling of PETP in toluene has been obtained. It was found that in the method of preirradiation in vacuum the initial grafting rate in Arrhenius plot has two linear ranges. Activation energy in low temperature range correlates with activation energy of PETP swelling. Activation energy in high temperature range is determined by kinetics of graft polymerization in the method of preirradiation in air. Arrhenius plot of the initial grafting rate gives the activation energy that approximately corresponds to the initiation of grafting with oxyradicals. Dependence of PETP matrix critical thickness on temperature has also been obtained. The form of this dependence is identical to the one of the rate of graft polymerization. 33 refs.; 6 figs.; 2 tabs

  6. Helical instability in film blowing process: Analogy to buckling instability

    Science.gov (United States)

    Lee, Joo Sung; Kwon, Ilyoung; Jung, Hyun Wook; Hyun, Jae Chun

    2017-12-01

    The film blowing process is one of the most important polymer processing operations, widely used for producing bi-axially oriented film products in a single-step process. Among the instabilities observed in this film blowing process, i.e., draw resonance and helical motion occurring on the inflated film bubble, the helical instability is a unique phenomenon portraying the snake-like undulation motion of the bubble, having the period on the order of few seconds. This helical instability in the film blowing process is commonly found at the process conditions of a high blow-up ratio with too low a freezeline position and/or too high extrusion temperature. In this study, employing an analogy to the buckling instability for falling viscous threads, the compressive force caused by the pressure difference between inside and outside of the film bubble is introduced into the simulation model along with the scaling law derived from the force balance between viscous force and centripetal force of the film bubble. The simulation using this model reveals a close agreement with the experimental results of the film blowing process of polyethylene polymers such as low density polyethylene and linear low density polyethylene.

  7. Electrical properties and surface morphology of electron beam evaporated p-type silicon thin films on polyethylene terephthalate for solar cells applications

    Science.gov (United States)

    Ang, P. C.; Ibrahim, K.; Pakhuruddin, M. Z.

    2015-04-01

    One way to realize low-cost thin film silicon (Si) solar cells fabrication is by depositing the films with high-deposition rate and manufacturing-compatible electron beam (e-beam) evaporation onto inexpensive foreign substrates such as glass or plastic. Most of the ongoing research is reported on e-beam evaporation of Si films on glass substrates to make polycrystalline solar cells but works combining both e-beam evaporation and plastic substrates are still scarce in the literature. This paper studies electrical properties and surface morphology of 1 µm electron beam evaporated Al-doped p-type silicon thin films on textured polyethylene terephthalate (PET) substrate for application as an absorber layer in solar cells. In this work, Si thin films with different doping concentrations (including an undoped reference) are prepared by e-beam evaporation. Energy dispersion X-ray (EDX) showed that the Si films are uniformly doped by Al dopant atoms. With increased Al/Si ratio, doping concentration increased while both resistivity and carrier mobility of the films showed opposite relationships. Root mean square (RMS) surface roughness increased. Overall, the Al-doped Si film with Al/Si ratio of 2% (doping concentration = 1.57×1016 atoms/cm3) has been found to provide the optimum properties of a p-type absorber layer for fabrication of thin film Si solar cells on PET substrate.

  8. Electrical properties and surface morphology of electron beam evaporated p-type silicon thin films on polyethylene terephthalate for solar cells applications

    Energy Technology Data Exchange (ETDEWEB)

    Ang, P. C.; Ibrahim, K.; Pakhuruddin, M. Z. [Nano-Optoelectronics Research and Technology Laboratory, School of Physics, Universiti Sains Malaysia, Minden 11800 Penang (Malaysia)

    2015-04-24

    One way to realize low-cost thin film silicon (Si) solar cells fabrication is by depositing the films with high-deposition rate and manufacturing-compatible electron beam (e-beam) evaporation onto inexpensive foreign substrates such as glass or plastic. Most of the ongoing research is reported on e-beam evaporation of Si films on glass substrates to make polycrystalline solar cells but works combining both e-beam evaporation and plastic substrates are still scarce in the literature. This paper studies electrical properties and surface morphology of 1 µm electron beam evaporated Al-doped p-type silicon thin films on textured polyethylene terephthalate (PET) substrate for application as an absorber layer in solar cells. In this work, Si thin films with different doping concentrations (including an undoped reference) are prepared by e-beam evaporation. Energy dispersion X-ray (EDX) showed that the Si films are uniformly doped by Al dopant atoms. With increased Al/Si ratio, doping concentration increased while both resistivity and carrier mobility of the films showed opposite relationships. Root mean square (RMS) surface roughness increased. Overall, the Al-doped Si film with Al/Si ratio of 2% (doping concentration = 1.57×10{sup 16} atoms/cm{sup 3}) has been found to provide the optimum properties of a p-type absorber layer for fabrication of thin film Si solar cells on PET substrate.

  9. A rapid process of Yba2Cu3O7-δ thin film fabrication using trifluoroacetate metal-organic deposition with polyethylene glycol additive

    DEFF Research Database (Denmark)

    Wu, Wei; Feng, Feng; Shi, Kai

    2013-01-01

    Trifluoroacetate metal-organic deposition (TFA-MOD) is a promising technique to fabricate YBa2Cu3O7-δ (YBCO) superconducting films. However, its slow pyrolysis process, which usually takes more than 10 h, constitutes a barrier for industrial production. In this study, polyethylene glycol (PEG......) was utilized to reduce the stress generation inside the coated films when the strong pyrolysis reactions happen. With the addition of 30 wt% PEG2000 to the precursor solution, a smooth film surface could be obtained through a rapid pyrolysis process of 15 min. After the optimizations of the crystallization...... and oxygenation processes, mass percentage and molecular weight of PEG additive, YBCO thin films with Jc of about 4.5 MA cm-2 (77 K, self-field) could be routinely fabricated using (20-30) wt% PEG(1000-2000) additive with a total treatment time of about 2 h including the 15 min pyrolysis process time. The effects...

  10. Coherence resonance in low-density jets

    Science.gov (United States)

    Zhu, Yuanhang; Gupta, Vikrant; Li, Larry K. B.

    2017-11-01

    Coherence resonance is a phenomenon in which the response of a stable nonlinear system to noise exhibits a peak in coherence at an intermediate noise amplitude. We report the first experimental evidence of coherence resonance in a purely hydrodynamic system, a low-density jet whose variants can be found in many natural and engineering systems. This evidence comprises four parts: (i) the jet's response amplitude increases as the Reynolds number approaches the instability boundary under a constant noise amplitude; (ii) as the noise amplitude increases, the amplitude distribution of the jet response first becomes unimodal, then bimodal, and finally unimodal again; (iii) a distinct peak emerges in the coherence factor at an intermediate noise amplitude; and (iv) for a subcritical Hopf bifurcation, the decay rate of the autocorrelation function exhibits a maximum at an intermediate noise amplitude, but for a supercritical Hopf bifurcation, the decay rate decreases monotonically with increasing noise amplitude. It is clear that coherence resonance can provide valuable information about a system's nonlinearity even in the unconditionally stable regime, opening up new possibilities for its use in system identification and flow control. This work was supported by the Research Grants Council of Hong Kong (Project No. 16235716 and 26202815).

  11. Low-Density Lipoproteins Oxidation and Endometriosis

    Directory of Open Access Journals (Sweden)

    Grzegorz Polak

    2013-01-01

    Full Text Available The etiopathogenesis of endometriosis still remains unknown. Recent data provide new valuable information concerning the role of oxidative stress in the pathophysiology of the disease. It has been proved that levels of different lipid peroxidation end products are increased in both peritoneal fluid (PF and serum of endometriotic patients. We assessed the concentration of oxidized low-density lipoproteins (oxLDL in PF of 110 women with different stages of endometriosis and 119 women with serous ( or dermoid ( ovarian cysts, as the reference groups. PF oxLDL levels were evaluated by ELISA. We found that concentrations of oxLDL in PF of endometriotic women were significantly higher compared to women with serous but not dermoid ovarian cysts. Interestingly, by analyzing concentrations of oxLDL in women with different stages of the disease, it was noted that they are significantly higher only in the subgroup of patients with stage IV endometriosis as compared to women with ovarian serous cysts. In case of minimal, mild, and moderate disease, PF oxLDL levels were similar to those noted in reference groups. Our results indicate that disrupted oxidative status in the peritoneal cavity of women with endometriosis may play a role in the pathogenesis of advanced stages of the disease.

  12. Improvement of the characteristics of chemical bath deposition-cadmium sulfide films deposited on an O{sub 2} plasma-treated polyethylene terephthalate substrate

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Donggun [Department of Electronic Engineering, Korea National University of Transportation, Chungju-si, Chungcheongbuk-do 380-702 (Korea, Republic of); Lee, Jaehyeong [School of Electronic and Electrical Engineering, Sungkyunkwan University 300, Cheoncheon-dong, Jangan-gu, Sunwon, Kyeonggi-do, 440-746 (Korea, Republic of); Song, Woochang, E-mail: wcsong@kangwon.ac.kr [Department of Electrical Engineering, Kangwon National University, Samcheok-si, Gangwon-do 245-711 (Korea, Republic of)

    2013-11-01

    We prepared cadmium sulfide (CdS) films on a polyethylene terephthalate (PET) substrate by a chemical bath deposition (CBD) technique. To improve the adhesion between the CdS film and the PET substrate, the substrate was pre-treated with an O{sub 2} plasma by an inductively coupled plasma. The surface characterizations of the pre-treated PET substrate were analyzed by a contact angle measurement and atomic force microscopy. The results showed that that O{sub 2} plasma-treated PET films had more hydrophilic surface. The hydrophilic property of the substrate is one of the important factors when a film is prepared by CBD. The structural and the optical properties of the CdS films, deposited on PET substrates, were analyzed by using a scanning electron microscope, X-ray diffraction and a UV–visible spectrophotometer. The CdS films were formed on a compact and granular structure. The optical transmittance was also improved. Therefore, the O{sub 2} plasma treatment of a PET surface is an effective method of preparing CdS films deposited on substrates by CBD. - Highlights: • Chemical bath deposition of CdS film for flexible solar cells • O{sub 2} plasma treatment improved adhesion between the CdS and polymer substrate • Identification of best fabrication condition of CdS window layers for flexible solar cells.

  13. Effects of a vanadium post-metallocene catalyst-induced polymer backbone inhomogeneity on UV oxidative degradation of the resulting polyethylene film

    KAUST Repository

    Atiqullah, M.

    2012-07-01

    A Group 5 post-metallocene precatalyst, (ONO)VCl(THF) 2 (ONO = a bis(phenolate)pyridine LX 2 pincer ligand), activated with modified methylaluminoxane (MMAO-3A) produced a linear ethylene homopolymer (nm-HomoPE)and an unusual inhomogeneous copolymer (nm-CopolyPE) with 1-hexene having very low backbone unsaturation. The nm-CopolyPE inhomogeneity was reflected in the distributions of short chain branches, 1-hexene composition, and methylene sequence length. The 1-hexene incorporation into the polyethylene backbone strongly depended on the molecular weight of the growing polymer chain. (ONO)VCl(THF) 2, because of site diversity and easier removal of a tertiary (vs. a secondary) hydrogen, produced a skewed short chain branching (SCB) profile, incorporating 1-hexene more efficiently in the low molecular weight region than in the high molecular weight region. The significant decrease in molecular weight by 1-hexene showed that the (ONO)VCl(THF) 2 catalytic sites were also highly responsive to chain-transfer directly to 1-hexene itself, producing vinyl and trans-vinylene termini. Subsequently, the effect of backbone inhomogeneity on the UV oxidative degradation of films made from both polyethylenes was investigated. The major functional group accumulated in the branched nm-CopolyPE film was carbonyl followed by carboxyl, then vinyl/ester, whereas that in the linear nm-HomoPE film was carboxyl. However, (carbonyl, carboxyl, vinyl, and ester) nm-CopolyPE film >> (carboxyl) nm-HomoPE film). The distributions of the tertiary C-H sites and methylene sequence length in the branched nm-CopolyPE film enhanced abstraction of H, decomposition of hydroperoxide group ROOH, and generation of carbonyl compounds as compared with those in the linear nm-HomoPE film. This clearly establishes the role played by the backbone inhomogeneity. The effect of short chain branches and sequence length distributions on peak melting temperature T pm, and most probably lamellar thickness L o, was

  14. Low density in liver of idiopathic portal hypertension

    International Nuclear Information System (INIS)

    Ishito, Hiroyuki

    1988-01-01

    In order to evaluate the diagnostic value of low density in liver on computed tomography (CT), CT scans of 11 patients with idiopathic portal hypertension (IPH) were compared with those from 22 cirrhotic patients, two patients with scarred liver and 16 normal subjects. Low densities on plain CT scans in patients with IPH were distinctly different from those observed in normal liver. Some of the low densities had irregular shape with unclear margin and were scattered near the liver surface, and others had vessel-like structures with unclear margin and extended as far as near the liver surface. Ten of the 11 patients with IPH had low densities mentioned above, while none of the 22 cirrhotic patients had such low densities. The present results suggest that the presence of low densities in liver on plain CT scan is clinically beneficial in diagnosis of IPH. (author)

  15. Thermomechanical behaviour of stabilized polyethylene irradiated with gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Novakovic, Lj; Markovic, V; Gal, O; Stannett, V T

    1986-01-01

    The moduli of elasticity at 150/sup 0/C for irradiated linear low density and low density polyethylenes, pure and with 0.5% antioxidants were determined using the penetration technique. Simultaneously, on similar samples, the gel content was measured. Analysing the radiation parameters and comparing data derived from the two methods the efficiency of radiation crosslinking of different polyethylenes and the effect of antioxidants is discussed.

  16. Thermomechanical behaviour of stabilized polyethylene irradiated with gamma rays

    International Nuclear Information System (INIS)

    Novakovic, Lj.; Markovic, V.; Gal, O.; Stannett, V.T.

    1986-01-01

    The moduli of elasticity at 150 C for irradiated linear low density and low density polyethylenes, pure and with 0.5% antioxidants were determined using the penetration technique. Simultaneously, on similar samples, the gel content was measured. Analysing the radiation parameters and comparing data derived from the two methods the efficiency of radiation crosslinking of different polyethylenes and the effect of antioxidants is discussed. (author)

  17. Refractory Coated/Lined Low Density Structures, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This project addresses the development of refractory coated or lined low density structures applicable for advanced future propulsion system technologies. The...

  18. Fabrication of honeycomb-structured poly(ethylene glycol)-block-poly(lactic acid) porous films and biomedical applications for cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Bingjian [Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250199 (China); College of chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Jinan 250014 (China); Zhu, Qingzeng, E-mail: qzzhu@sdu.edu.cn [Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250199 (China); Yao, Linli [Key Laboratory of the Ministry of Education for Experimental Teratology, Department of Histology and Embryology, Shandong University School of Medicine, 250012 Jinan (China); Hao, Jingcheng [Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250199 (China)

    2015-03-30

    Graphical abstract: - Highlights: • Honeycomb-structured PEG-PLA porous films were fabricated. • The organization of pores depends on molecular weight ratio of PEG-to-PLA block. • The pores in the film were internally decorated with a layer of PEG. • The honeycomb-structured PEG-PLA film was suitable as a substrate for cell growth. - Abstract: A series of poly(ethylene glycol)-block-poly(lactic acid) (PEG-PLA) copolymers with a hydrophobic PLA block of different molecular weights and a fixed length hydrophilic PEG were synthesized successfully and characterized. These amphiphilic block copolymers were used to fabricate honeycomb-structured porous films using the breath figure (BF) templating technique. The surface topology and composition of the highly ordered pattern film were further characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and fluorescence microscopy. The results indicated that the PEG-to-PLA block molecular weight ratio influenced the BF film surface topology. The film with the best ordered pores was obtained with a PEG-to-PLA ratio of 2.0 × 10{sup 3}:3.0 × 10{sup 4}. The self-organization of the hydrophilic PEG chains within the pores was confirmed by XPS and fluorescence labeled PEG. A model is proposed to elucidate the stabilization process of the amphiphilic PEG-PLA aggregated architecture on the water droplet-based templates. In addition, GFP-U87 cell viability has been investigated by MTS test and the cell morphology on the honeycomb-structured PEG-PLA porous film has been evaluated using phase-contrast microscope. This porous film is shown to be suitable as a matrix for cell growth.

  19. Fabrication of honeycomb-structured poly(ethylene glycol)-block-poly(lactic acid) porous films and biomedical applications for cell growth

    International Nuclear Information System (INIS)

    Yao, Bingjian; Zhu, Qingzeng; Yao, Linli; Hao, Jingcheng

    2015-01-01

    Graphical abstract: - Highlights: • Honeycomb-structured PEG-PLA porous films were fabricated. • The organization of pores depends on molecular weight ratio of PEG-to-PLA block. • The pores in the film were internally decorated with a layer of PEG. • The honeycomb-structured PEG-PLA film was suitable as a substrate for cell growth. - Abstract: A series of poly(ethylene glycol)-block-poly(lactic acid) (PEG-PLA) copolymers with a hydrophobic PLA block of different molecular weights and a fixed length hydrophilic PEG were synthesized successfully and characterized. These amphiphilic block copolymers were used to fabricate honeycomb-structured porous films using the breath figure (BF) templating technique. The surface topology and composition of the highly ordered pattern film were further characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and fluorescence microscopy. The results indicated that the PEG-to-PLA block molecular weight ratio influenced the BF film surface topology. The film with the best ordered pores was obtained with a PEG-to-PLA ratio of 2.0 × 10 3 :3.0 × 10 4 . The self-organization of the hydrophilic PEG chains within the pores was confirmed by XPS and fluorescence labeled PEG. A model is proposed to elucidate the stabilization process of the amphiphilic PEG-PLA aggregated architecture on the water droplet-based templates. In addition, GFP-U87 cell viability has been investigated by MTS test and the cell morphology on the honeycomb-structured PEG-PLA porous film has been evaluated using phase-contrast microscope. This porous film is shown to be suitable as a matrix for cell growth

  20. Microwave characteristics of low density flaky magnetic particles

    International Nuclear Information System (INIS)

    Wenqiang, Zhang; Deyuan, Zhang; Jun, Cai

    2013-01-01

    Diatomite coated with thin Fe films were obtained by the Chemical Vapor Deposition process. The resultant Fe-coated flaky diatomite particles had low densities (2.7–4.0 g/cm 3 ) and high saturation magnetization (93–157 emu/g). Annealing treatment led to grain growth and an increased saturation magnetization. The high frequency properties of the composites consisting of Fe-coated flaky diatomite particles and wax were investigated. The permittivity and permeability increased with increasing flaky magnetic particles content in the composite and increasing the Fe weight percentage of the particles. The reflection loss of the composite was found dependent on the absorber material thickness, wax:flaky magnetic particles ratios, the Fe content, as well as the annealing treatment. At a thickness of 1 mm, the composite records a minimum reflection loss of −18 dB at 6 GHz. - Highlights: ► We synthesize the flaky magnetic particles with the diatomite as template. ► The flaky magnetic particles coating layers are constituted by α-Fe. ► The flaky magnetic particles have good static magnetic properties. ► The flaky magnetic particles are a kind light weight high performance microwave absorber

  1. Microwave characteristics of low density flaky magnetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Wenqiang, Zhang, E-mail: zwqzwqzwqzwq@126.com [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, Beihang University, Beijing 100191 (China); College of Engineering, China Agricultural University, Beijing 100083 (China); Deyuan, Zhang [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, Beihang University, Beijing 100191 (China); Jun, Cai, E-mail: jun_cai@buaa.edu.cn [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, Beihang University, Beijing 100191 (China)

    2013-04-15

    Diatomite coated with thin Fe films were obtained by the Chemical Vapor Deposition process. The resultant Fe-coated flaky diatomite particles had low densities (2.7–4.0 g/cm{sup 3}) and high saturation magnetization (93–157 emu/g). Annealing treatment led to grain growth and an increased saturation magnetization. The high frequency properties of the composites consisting of Fe-coated flaky diatomite particles and wax were investigated. The permittivity and permeability increased with increasing flaky magnetic particles content in the composite and increasing the Fe weight percentage of the particles. The reflection loss of the composite was found dependent on the absorber material thickness, wax:flaky magnetic particles ratios, the Fe content, as well as the annealing treatment. At a thickness of 1 mm, the composite records a minimum reflection loss of −18 dB at 6 GHz. - Highlights: ► We synthesize the flaky magnetic particles with the diatomite as template. ► The flaky magnetic particles coating layers are constituted by α-Fe. ► The flaky magnetic particles have good static magnetic properties. ► The flaky magnetic particles are a kind light weight high performance microwave absorber.

  2. Evaluation of polyethylene glycol/polylactic acid films in the prevention of adhesions in the rabbit adhesion formation and reformation sidewall models.

    Science.gov (United States)

    Rodgers, K; Cohn, D; Hotovely, A; Pines, E; Diamond, M P; diZerega, G

    1998-03-01

    To assess the efficacy of bioresorbable films consisting of various polyethylene glycol 6000 and polylactic acid block copolymers on the formation and reformation of adhesions in rabbit models of adhesion development between the sidewall to the adjacent cecum and bowel. The composition of the different polymers was expressed by the number of monomeric units in the block, namely, ethylene oxide (EO) and lactic acid (LA), respectively. Studies of the efficacy of EO/LA films were conducted in rabbit sidewall adhesion formation studies in the presence and absence of blood and in rabbit adhesion reformation studies. REPEL (Life Medical Sciences, Edison, NJ), a film of EO/LA ratio 3.0 manufactured under commercial conditions, was also tested in these animal models. University-based laboratory. New Zealand white rabbits. Placement of films of various EO/LA ratios at the site of injury to the parietal peritoneum. Adhesion formation and reformation. Films of various EO/LA ratios, Seprafilm (Genzyme, Cambridge, MA) and Interceed (Johnson and Johnson Medical, Arlington, TX) placed over an area of excised sidewall at the time of initial injury were highly efficacious in the prevention of adhesion formation. A film of EO/LA ratio 3.7, in contrast with Interceed, was also shown to maintain maximal efficacy in the reduction of adhesion formation in the presence of blood. Further, a film of EO/LA ratio 3.0 produced under commercial conditions, REPEL, was highly efficacious in reducing adhesion development in the rabbit models of adhesion and reformation. These studies suggest that bioresorbable EO/LA films reduced adhesion development in rabbit models of adhesion formation and reformation.

  3. Effects of Interphase Modification and Biaxial Orientation on Dielectric Properties of Poly(ethylene terephthalate)/Poly(vinylidene fluoride-co-hexafluoropropylene) Multilayer Films.

    Science.gov (United States)

    Yin, Kezhen; Zhou, Zheng; Schuele, Donald E; Wolak, Mason; Zhu, Lei; Baer, Eric

    2016-06-01

    Recently, poly(vinylidene fluoride) (PVDF)-based multilayer films have demonstrated enhanced dielectric properties, combining high energy density and high dielectric breakdown strength from the component polymers. In this work, further enhanced dielectric properties were achieved through interface/interphase modulation and biaxial orientation for the poly(ethylene terephthalate)/poly(methyl methacrylate)/poly(vinylidene fluoride-co-hexafluoropropylene) [PET/PMMA/P(VDF-HFP)] three-component multilayer films. Because PMMA is miscible with P(VDF-HFP) and compatible with PET, the interfacial adhesion between PET and P(VDF-HFP) layers should be improved. Biaxial stretching of the as-extruded multilayer films induced formation of highly oriented fibrillar crystals in both P(VDF-HFP) and PET, resulting in improved dielectric properties with respect to the unstretched films. First, the parallel orientation of PVDF crystals reduced the dielectric loss from the αc relaxation in α crystals. Second, biaxial stretching constrained the amorphous phase in P(VDF-HFP) and thus the migrational loss from impurity ions was reduced. Third, biaxial stretching induced a significant amount of rigid amorphous phase in PET, further enhancing the breakdown strength of multilayer films. Due to the synergistic effects of improved interfacial adhesion and biaxial orientation, the PET/PMMA/P(VDF-HFP) 65-layer films with 8 vol % PMMA exhibited optimal dielectric properties with an energy density of 17.4 J/cm(3) at breakdown and the lowest dielectric loss. These three-component multilayer films are promising for future high-energy-density film capacitor applications.

  4. Development of Anti-Insect Microencapsulated Polypropylene Films Using a Large Scale Film Coating System.

    Science.gov (United States)

    Song, Ah Young; Choi, Ha Young; Lee, Eun Song; Han, Jaejoon; Min, Sea C

    2018-04-01

    Films containing microencapsulated cinnamon oil (CO) were developed using a large-scale production system to protect against the Indian meal moth (Plodia interpunctella). CO at concentrations of 0%, 0.8%, or 1.7% (w/w ink mixture) was microencapsulated with polyvinyl alcohol. The microencapsulated CO emulsion was mixed with ink (47% or 59%, w/w) and thinner (20% or 25%, w/w) and coated on polypropylene (PP) films. The PP film was then laminated with a low-density polyethylene (LDPE) film on the coated side. The film with microencapsulated CO at 1.7% repelled P. interpunctella most effectively. Microencapsulation did not negatively affect insect repelling activity. The release rate of cinnamaldehyde, an active repellent, was lower when CO was microencapsulated than that in the absence of microencapsulation. Thermogravimetric analysis exhibited that microencapsulation prevented the volatilization of CO. The tensile strength, percentage elongation at break, elastic modulus, and water vapor permeability of the films indicated that microencapsulation did not affect the tensile and moisture barrier properties (P > 0.05). The results of this study suggest that effective films for the prevention of Indian meal moth invasion can be produced by the microencapsulation of CO using a large-scale film production system. Low-density polyethylene-laminated polypropylene films printed with ink incorporating microencapsulated cinnamon oil using a large-scale film production system effectively repelled Indian meal moth larvae. Without altering the tensile and moisture barrier properties of the film, microencapsulation resulted in the release of an active repellent for extended periods with a high thermal stability of cinnamon oil, enabling commercial film production at high temperatures. This anti-insect film system may have applications to other food-packaging films that use the same ink-printing platform. © 2018 Institute of Food Technologists®.

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    Science.gov (United States)

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

    2008-10-01

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

  7. Textured surface boron-doped ZnO transparent conductive oxides on polyethylene terephthalate substrates for Si-based thin film solar cells

    International Nuclear Information System (INIS)

    Chen Xinliang; Lin Quan; Ni Jian; Zhang Dekun; Sun Jian; Zhao Ying; Geng Xinhua

    2011-01-01

    Textured surface boron-doped zinc oxide (ZnO:B) thin films were directly grown via low pressure metal organic chemical vapor deposition (LP-MOCVD) on polyethylene terephthalate (PET) flexible substrates at low temperatures and high-efficiency flexible polymer silicon (Si) based thin film solar cells were obtained. High purity diethylzinc and water vapors were used as source materials, and diborane was used as an n-type dopant gas. P-i-n silicon layers were fabricated at ∼ 398 K by plasma enhanced chemical vapor deposition. These textured surface ZnO:B thin films on PET substrates (PET/ZnO:B) exhibit rough pyramid-like morphology with high transparencies (T ∼ 80%) and excellent electrical properties (Rs ∼ 10 Ω at d ∼ 1500 nm). Finally, the PET/ZnO:B thin films were applied in flexible p-i-n type silicon thin film solar cells (device structure: PET/ZnO:B/p-i-n a-Si:H/Al) with a high conversion efficiency of 6.32% (short-circuit current density J SC = 10.62 mA/cm 2 , open-circuit voltage V OC = 0.93 V and fill factor = 64%).

  8. Surface modification of polyethylene by plasma

    International Nuclear Information System (INIS)

    Colin O, E.

    2003-01-01

    The products made of polyethylene (PE) go from construction materials, electric insulating until packing material. The films for bags and pack occupy 83.6% of the distribution of the market of PE approximately. The enormous quantity of PE that is generated by its indiscriminate use brings as consequence a deterioration to the atmosphere, due to the long life that they present as waste. This work is a study on the modification of low density polyethylene films. In this type of thin materials, the changes in the surface meet with largely on the conformation of the rest of the material. To induce changes that modify the surface of PE, plasmas were used with reactive atmospheres of air, oxygen and nitrogen. The experimentation that was carries out went to introduce the PE to a cylindrical reactor where it was generated the plasma of air, oxygen and nitrogen to different times of exposure. After having carried out the exposure to the plasma, it was found that in the polyethylene it modifies their morphology, crystallinity, hydrophobicity, composition and electric conductivity. The analytical techniques that were used to characterize later to the polyethylene of being in contact with the plasma were: X-ray diffraction, Scanning Electron Microscopy, Infrared spectroscopy, Electric conductivity, Angle of contact and finally Thermal Gravimetric Analysis. The content of this work it is presented in five chapters: In the chapter 1 there are presented some general concepts of plasma and of the one polymer in study PE. In the chapter 2 it is made a general revision on modification of surfaces, as well as the properties that were modified in polymeric materials that were exposed to plasma in previous works. In the chapter 3 the experimental part and the conditions used are described in the modification of the PE. Also in this chapter a brief description it is made of the used characterization techniques. The results and discussion are presented in the chapter 4. These results

  9. Amine modified polyethylenes, prepared in near critical propane, as adhesion promoting agents in multilayered HDPE/PET films

    NARCIS (Netherlands)

    Gooijer, de J.M.; Scheltus, M.; Koning, C.E.

    2001-01-01

    High d. polyethylene (HDPE) grafted with 0.13, 0.40 and 1.04 wt% maleic anhydride (abbreviation PEMA) was modified with an excess of a variety of diamines in near crit. propane. The resulting amic acid groups were quant. imidized to the corresponding imide (PEMI) in the melt. Increasing the

  10. Multivariate analysis of DSC-XRD simultaneous measurement data: a study of multistage crystalline structure changes in a linear poly(ethylene imine) thin film.

    Science.gov (United States)

    Kakuda, Hiroyuki; Okada, Tetsuo; Otsuka, Makoto; Katsumoto, Yukiteru; Hasegawa, Takeshi

    2009-01-01

    A multivariate analytical technique has been applied to the analysis of simultaneous measurement data from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) in order to study thermal changes in crystalline structure of a linear poly(ethylene imine) (LPEI) film. A large number of XRD patterns generated from the simultaneous measurements were subjected to an augmented alternative least-squares (ALS) regression analysis, and the XRD patterns were readily decomposed into chemically independent XRD patterns and their thermal profiles were also obtained at the same time. The decomposed XRD patterns and the profiles were useful in discussing the minute peaks in the DSC. The analytical results revealed the following changes of polymorphisms in detail: An LPEI film prepared by casting an aqueous solution was composed of sesquihydrate and hemihydrate crystals. The sesquihydrate one was lost at an early stage of heating, and the film changed into an amorphous state. Once the sesquihydrate was lost by heating, it was not recovered even when it was cooled back to room temperature. When the sample was heated again, structural changes were found between the hemihydrate and the amorphous components. In this manner, the simultaneous DSC-XRD measurements combined with ALS analysis proved to be powerful for obtaining a better understanding of the thermally induced changes of the crystalline structure in a polymer film.

  11. Surface grafting of poly(ethylene glycol) onto poly(acrylamide-co-vinyl amine) cross-linked films under mild conditions.

    Science.gov (United States)

    Yamamoto, Y; Sefton, M V

    1998-01-01

    Poly(ethylene glycol) (PEG) was grafted onto poly(acrylamide-co-vinyl amine) (poly(AM-co-VA)) film using tresylated PEG (TPEG) at 37 degrees C in aqueous buffers (pH 7.4) with a view to surface-modifying microencapsulated mammalian cells. Poly(AM-co-VA) film was synthesized by Hofmann degradation of a cross-linked poly(acrylamide) film. Conversion to vinyl amine on the surface of the film was approximately 50%, but bulk conversion was not observed; surface specificity was thought to be the result of cleavage of aminated polymer chains at the surface due to chain scission. Reaction between primary amine and TPEG gave a graft yield of 2 mol% (based on XPS) with respect to available surface amine groups, equivalent to 54 mol% ethylene oxide based on monomer units. Physical adsorption of non-activated polymer was done under identical conditions as a control and the difference in oxygen content was significant compared to TPEG. The type of buffer agent and buffer concentration did not influence graft yields. This graft reaction, which was completed in as little as 2 h was considered to be mild enough to be used for a surface modification of microcapsules containing cells without affecting their viability. Such a surface modification technique may prove to be a useful means of enhancing the biocompatibility of microcapsules (or any tissue engineering construct) even after cell encapsulation or seeding.

  12. Structural and optical properties of Ag-doped copper oxide thin films on polyethylene napthalate substrate prepared by low temperature microwave annealing

    Energy Technology Data Exchange (ETDEWEB)

    Das, Sayantan; Alford, T. L. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA and School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States)

    2013-06-28

    Silver doped cupric oxide thin films are prepared on polyethylene naphthalate (flexible polymer) substrates. Thin films Ag-doped CuO are deposited on the substrate by co-sputtering followed by microwave assisted oxidation of the metal films. The low temperature tolerance of the polymer substrates led to the search for innovative low temperature processing techniques. Cupric oxide is a p-type semiconductor with an indirect band gap and is used as selective absorption layer solar cells. X-ray diffraction identifies the CuO phases. Rutherford backscattering spectrometry measurements confirm the stoichiometry of each copper oxide formed. The surface morphology is determined by atomic force microscopy. The microstructural properties such as crystallite size and the microstrain for (-111) and (111) planes are calculated and discussed. Incorporation of Ag led to the lowering of band gap in CuO. Consequently, it is determined that Ag addition has a strong effect on the structural, morphological, surface, and optical properties of CuO grown on flexible substrates by microwave annealing. Tauc's plot is used to determine the optical band gap of CuO and Ag doped CuO films. The values of the indirect and direct band gap for CuO are found to be 2.02 eV and 3.19 eV, respectively.

  13. 77 FR 20357 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates: Final Results of...

    Science.gov (United States)

    2012-04-04

    ... latex. Tracing and drafting film is also excluded. PET Film is classifiable under subheading 3920.62.00... on the Web at http://ia.ita.doc.gov/frn . The signed Decision Memorandum and the electronic versions...

  14. 78 FR 14266 - Polyethylene Terephthalate Film, Sheet, and Strip From Taiwan: Notice of Correction to the Final...

    Science.gov (United States)

    2013-03-05

    ... Milton Koch, AD/CVD Operations, Office 6, Import Administration, International Trade Administration, U.S... film, sheet, and strip (PET Film) from Taiwan.\\1\\ The period of review covered July 1, 2010, through... an incorrect case number associated with PET Film from Taiwan (i.e., incorrect case number A-533-824...

  15. 78 FR 29700 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates: Final Results of...

    Science.gov (United States)

    2013-05-21

    ... Film, Sheet, and Strip From the United Arab Emirates: Final Results of Antidumping Duty Administrative... (PET Film) from the United Arab Emirates.\\1\\ This review covers two producers/exporters of subject... Terephthalate Film, Sheet, and Strip from the United Arab Emirates: Preliminary Results of Antidumping Duty...

  16. Mechanical properties of polyamide 6,6/low density polyethylene blend by ionizing radiation

    International Nuclear Information System (INIS)

    Pino, Eddy S.; Feitosa, Marcos A.F.

    2007-01-01

    Polymer blending is a growing scientific and commercial development activity. In most of the cases, polymeric blends are formed by thermodynamically immiscible components. Such blends require the use of compatibilizers that, often, are copolymers, graft copolymers or any mean that improves the dispersion and adhesion of the blend phases. Compatibility of a polymer blend plays an important role in determining the blend properties for its end use. In this work, the improvement of mechanical properties of PA 6,6/LDPE 75/25% wt/wt composition blend, using electron radiation, was studied. Samples for mechanical test were melt-mixed in an extruder and then injection-molded. These samples were electron irradiated to overall doses of 50, 100, 150, 200 and 250 kGy. Tensile measurements have shown that the strength at break increases with an increase of radiation dose. Hardness Shore D measurements show that this property also increases as a function of radiation dose. On the other hand, Impact Izod tests show that the resistance to impact decreases with the increase of radiation dose. The behavior of these bulk and surface properties implies that ionizing radiation produces changes in the mechanical performance of the irradiated blend due to a combined radiation inducing effects, cross-linking and the compatibility of blend components. (author)

  17. Partitioning of hydrophobic organic contaminants between polymer and lipids for two silicones and low density polyethylene

    DEFF Research Database (Denmark)

    Smedes, Foppe; Rusina, Tatsiana P.; Beeltje, Henry

    2017-01-01

    Polymers are increasingly used for passive sampling of neutral hydrophobic organic substances (HOC) in environmental media including water, air, soil, sediment and even biological tissue. The equilibrium concentration of HOC in the polymer can be measured and then converted into equilibrium conce...... for a thermodynamically sound risk assessment of HOC contained in microplastics....

  18. The energy distribution function of excess electrons trapped in the pulse irradiated low density polyethylene (LDPE)

    International Nuclear Information System (INIS)

    Wysocki, S.; Mazurek, L.; Karolczak, S.; Kroh, J.

    1995-01-01

    Distribution function D (E) of electrons trapped in irradiated LDPE was calculated on the basis of time resolved absorption spectra recorded at temperatures of 20-250 K. Variation of absorption spectra with time and temperature were observed and discussed in terms of simultaneous decay and relocation of electrons from shallow to deeper traps. Results obtained imply domination of trap limited transport for shallowly trapped electrons. For deeper traps, hopping mechanism is prevailing. (author)

  19. Space charge profiles in low density polyethylene samples containing a permittivity/conductivity gradient

    DEFF Research Database (Denmark)

    Bambery, K.R.; Fleming, R.J.; Holbøll, Joachim

    2001-01-01

    .5×107 V m-1. Current density was also measured as a function of temperature and field. Space charge due exclusively to the temperature gradient was detected, with density of order 0.01 C m-3. The activation energy associated with the transport of electrons through the bulk was calculated as 0.09 e...

  20. Partitioning of hydrophobic organic contaminants between polymer and lipids for two silicones and low density polyethylene

    NARCIS (Netherlands)

    Smedes, F.; Rusina, T.P.; Beeltje, H.; Mayer, P.

    2017-01-01

    Polymers are increasingly used for passive sampling of neutral hydrophobic organic substances (HOC) in environmental media including water, air, soil, sediment and even biological tissue. The equilibrium concentration of HOC in the polymer can be measured and then converted into equilibrium

  1. Properties of Extruded Blends Based on Low Density Polyethylene and Polyaniline

    OpenAIRE

    Cupul, Carlos V; Cruz, Ricardo H; Caballero, Alejandra; Rangel, Luis M

    2008-01-01

    Se estudia el efecto de la adición de un complejo electro-conductor de polianilina (PANIPOL) sobre la conductividad eléctrica, la resistencia mecánica y la microestructura de materiales compuestos poliméricos. El análisis se realizó en extrudidos de polietileno de baja densidad-PANIPOL, con diferentes contenidos del relleno conductor, los cuales fueron obtenidos en forma de filamento mediante extrusión capilar. La conductividad volumétrica se calculó a partir de la resistencia eléctrica usand...

  2. Viscosity overshoot in the start-up of uniaxial elongation of low density polyethylene melts

    DEFF Research Database (Denmark)

    Rasmussen, Henrik K.; Nielsen, Jens Kromann; Bach, Anders

    2005-01-01

    The transient uniaxial elongational viscosity of BASF Lupolen 1840D and 3020D melts has been measured on a filament stretch rheometer up to Hencky strains of 6-7. The elongational viscosity of both melts was measured at 130 degrees C within a broad range of elongational rates. At high elongation ...

  3. Influence of Pro-Oxidant on Photodegradation of a Low-Density Polyethylene-Nanosilica Composite

    Science.gov (United States)

    Use of polymer nanocomposites is burgeoning and they represent one of the fastest growing components of the manufactured nanomaterials market. Incorporation of nanoscale fillers in these plastics significantly improves their stiffness and other key mechanical properties. Although...

  4. Sago Starch-Mixed Low-Density Polyethylene Biodegradable Polymer: Synthesis and Characterization

    Directory of Open Access Journals (Sweden)

    Md Enamul Hoque

    2013-01-01

    Full Text Available This research focuses on synthesis and characterization of sago starch-mixed LDPE biodegradable polymer. Firstly, the effect of variation of starch content on mechanical property (elongation at break and Young’s modulus and biodegradability of the polymer was studied. The LDPE was combined with 10%, 30%, 50%, and 70% of sago for this study. Then how the cross-linking with trimethylolpropane triacrylate (TMPTA and electron beam (EB irradiation influence the mechanical and thermal properties of the polymer was investigated. In the 2nd study, to avoid overwhelming of data LDPE polymer was incorporated with only 50% of starch. The starch content had direct influence on mechanical property and biodegradability of the polymer. The elongation at break decreased with increase of starch content, while Young’s modulus and mass loss (i.e., degradation were found to increase with increase of starch content. Increase of cross-linker (TMPTA and EB doses also resulted in increased Young’s modulus of the polymer. However, both cross-linking and EB irradiation processes rendered lowering of polymer’s melting temperature. In conclusion, starch content and modification processes play significant roles in controlling mechanical, thermal, and degradation properties of the starch-mixed LDPE synthetic polymer, thus providing the opportunity to modulate the polymer properties for tailored applications.

  5. Low density polyethylene (LDPE) / poli (3-hydroxy-butyrate) (PHB) blends filled with castor oil cake

    International Nuclear Information System (INIS)

    Rocha, M.C.G.; Oliveira, C.I.R. de; Sanches, M.C.; Coelho, N.N.

    2014-01-01

    Blends of PHB and LDPE were prepared by melt mixing in a Haake internal mixer. Castor oil pressed cake was used as filler for the blends. In order to improve the interfacial adhesion between the filler and the polymers, a mercerization process with 5% NaOH solution was employed. This process was evaluated by several techniques such as: X-Ray diffraction, infrared spectroscopy and scanning electron microscopy (SEM). The mechanical properties were evaluated by traditional tensile stress-strain tests (ASTM D- 638). The obtained results showed that the mercerization process leads to better adhesion properties. The Young Modulus of the blends presented a tendency to increase with the addition of the castor oil cake.(author)

  6. Clustering and Symmetry Energy in a Low Density Nuclear Gas

    International Nuclear Information System (INIS)

    Kowalski, S.; Natowitz, J.B.; Shlomo, S.; Wada, R.; Hagel, K.; Wang, J.; Materna, T.; Chen, Z.; Ma, Y.G.; Qin, L.; Botvina, A.S.; Fabris, D.; Lunardon, M.; Moretto, S.; Nebbia, G.; Pesente, S.; Rizzi, V.; Viesti, G.; Cinausero, M.; Prete, G.; Keutgen, T.; El Masri, Y.; Majka, Z.; Ono, A.

    2007-01-01

    Temperature and density dependent symmetry energy coefficients have been derived from isoscaling analyses of the yields of nuclei with A= 64 Zn projectiles with 92 Mo and 197 Au target nuclei. The symmetry energies at low density are larger than those obtained in mean field calculations, reflecting the clustering of low density nuclear matter. They are in quite good agreement with results of a recently proposed Virial Equation of State calculation

  7. Laser reflection method for determination of shear stress in low density transitional flows

    Science.gov (United States)

    Sathian, Sarith P.; Kurian, Job

    2006-03-01

    The details of laser reflection method (LRM) for the determination of shear stress in low density transitional flows are presented. The method is employed to determine the shear stress due to impingement of a low density supersonic free jet issuing out from a convergent divergent nozzle on a flat plate. The plate is smeared with a thin oil film and kept parallel to the nozzle axis. For a thin oil film moving under the action of aerodynamic boundary layer, the shear stress at the air-oil interface is equal to the shear stress between the surface and air. A direct and dynamic measurement of the oil film slope generated by the shear force is done using a position sensing detector (PSD). The thinning rate of the oil film is directly measured which is the major advantage of the LRM. From the oil film slope history, calculation of the shear stress is done using a three-point formula. The range of Knudsen numbers investigated is from 0.028 to 0.516. Pressure ratio across the nozzle varied from 3,500 to 8,500 giving highly under expanded free jets. The measured values of shear, in the overlapping region of experimental parameters, show fair agreement with those obtained by force balance method and laser interferometric method.

  8. Hemodynamics alter arterial low-density lipoprotein metabolism

    International Nuclear Information System (INIS)

    Warty, V.S.; Calvo, W.J.; Berceli, S.A.; Pham, S.M.; Durham, S.J.; Tanksale, S.K.; Klein, E.C.; Herman, I.M.; Borovetz, H.S.

    1989-01-01

    We have investigated the role of hemodynamic factors on low-density lipoprotein transport and metabolism in the intact arterial wall. Freshly excised canine carotid blood vessels were exposed to well-defined pulsatile flow in vitro for continuous periods up to 20 hours. We chose to impose the following hemodynamic conditions on our test carotid arteries: normotension, hypertension (at physiologic flow conditions), and hypertension coupled with elevated flow of canine serum perfusate. In several experiments the effect of endothelial denudation was examined in carotid arteries exposed to normotensive pulsatile flow. A trapped ligand method was used for quantitating low-density lipoprotein uptake and metabolism in the arterial wall. The distribution of both intact and degraded low-density lipoprotein fractions was determined from measurements of radiolabelled low-density lipoprotein activity within thin radial sections of perfused arteries. Our results suggest that both hypertensive hemodynamic simulations exacerbate the uptake of low-density lipoprotein within the arterial wall (by a factor of three to nine). The percentage of low-density lipoprotein that undergoes irreversible degradation falls from 41% under normotensive conditions to below 30% when hypertensive conditions are imposed, indicating that degradative processes are not proportionally elevated with the accelerated influx. A similar pattern is observed for deendothelialized vessels

  9. Metabolism of cholesteryl esters of rat very low density lipoproteins.

    Science.gov (United States)

    Faergeman, O; Havel, R J

    1975-06-01

    Rat very low density lipoproteins (d smaller than 1.006), biologically labeled in esterified and free cholesterol, were obtained form serum 6 h after intravenous injection of particulate (3-H) cholesterol. When injected into recipient animals, the esterified cholesterol was cleared form plasma with a half-life of 5 min. After 15 min, 71% of the injected esterified (3-H) cholesterol had been taken up by the liver, where it was rapidly hydrolyzed. After 60 min only 3.3% of the amount injected had been transferred, via lipoproteins of intermediate density, to the low density lipoproteins of plasma (d 1.019-1.063). Both uptake in the liver and transfer to low density lipoproteins occurred without change of distribution of 3-H in the various cholesteryl esters. 3-H appearing in esterified cholesterol of high density lipoproteins (d greater than 1.063) was derived from esterification, presumably by lecithin: cholesterol acyltransferase, of simultaneously injected free (3-H) cholesterol. Content of free (3-H) cholesterol in the very low density lipoproteins used for injection could be reduced substantially by incubation with erythrocytes. This procedure, however, increased the rate of clearance of the lipoproteins after injection into recipient rats. These studies show that hepatic removal is the major catabolic pathway for cholesteryl esters of rat very low density lipoproteins and that transfer to low density lipoproteins occurs to only a minor extent.

  10. Radiation induced graft copolymerization of n-butyl acrylate onto poly(ethylene terephthalate) (PET) films and thermal properties of the obtained graft copolymer

    Energy Technology Data Exchange (ETDEWEB)

    Ping Xiang [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Wang Mozhen, E-mail: pstwmz@ustc.edu.c [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ge Xuewu, E-mail: xwge@ustc.edu.c [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2011-05-15

    n-Butyl acrylate (BA) was successfully grafted onto poly(ethylene terephthalate) (PET) film using simultaneous radiation induced graft copolymerization with gamma rays. When BA concentration ranges from 20% to 30%, the Degree of Grafting (DG), measured by gravimetry and {sup 1}H NMR, increases with the monomer concentration and absorbed dose, but decreases with dose rate from 0.83 to 2.53 kGy/h. The maximum DG can reach up to 22.1%. The thermal transition temperatures such as glass-transition temperature (T{sub g}) and cold-crystallization temperature (T{sub cc}) of PET in grafted films were little different from those in original PET film, indicating that microphase separation occurred between PBA side chains and PET backbone. This work implied that if PET/elastomers (e.g., acrylate rubber) blends are radiated by high energy gamma rays under a certain condition, PET-g-polyacrylate copolymer may be produced in-situ, which will improve the compatibility between PET and the elastomers so as to improve the integral mechanical properties of PET based engineering plastic.

  11. Silk fibroin immobilization on poly(ethylene terephthalate) films: Comparison of two surface modification methods and their effect on mesenchymal stem cells culture

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Meini; Yao, Jinrong; Chen, Xin; Huang, Lei; Shao, Zhengzhong, E-mail: zzshao@fudan.edu.cn

    2013-04-01

    Silk fibroin (SF) has played a curial role for the surface modification of conventional materials to improve the biocompatibility, and SF modified poly(ethylene terephthalate) (PET) materials have potential applications on tissue engineering such as artificial ligament, artificial vessel, artificial heart valve sewing cuffs dacron and surgical mesh engineering. In this work, SF was immobilized onto PET film via two different methods: 1) plasma pretreatment followed by SF dip coating (PET-SF) and 2) plasma-induce acrylic acid graft polymerization and subsequent covalent immobilization of SF on PET film (PET-PAA-SF). It could be found that plasma treatment provided higher surface roughness which was suitable for further SF dip coating, while grafted poly(acrylic acid) (PAA) promised the covalent bonding between SF and PAA. ATR-FTIR adsorption band at 3284 cm{sup −1}, 1623 cm{sup −1} and 1520 cm{sup −1} suggested the successful introduction of SF onto PET surface, while the amount of immobilized SF of PET-SF was higher than PET-PAA-SF according to XPS investigation (0.29 vs 0.23 for N/C ratio). Surface modified PET film was used as substrate for mesenchymal stem cells (MSCs) culture, the cells on PET-SF surface exhibited optimum density compared to PET-PAA-SF according to CCK-8 assays, which indicated that plasma pretreatment followed by SF dip coating was a simple and effective way to prepare biocompatible PET surface. Highlights: ► Silk fibroins were immobilized onto PET films with or without the linker of PAA. ► Various techniques were performed to characterize the modified surfaces ► Plasma treatment followed by SF dip coating introduced more SF onto PET films. ► Compare to PET-PAA-SF, PET-SF has better biocompatibility base on MSCs culture.

  12. Structure and gas-barrier properties of amorphous hydrogenated carbon films deposited on inner walls of cylindrical polyethylene terephthalate by plasma-enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Li Jing; Gong Chunzhi; Tian Xiubo; Yang Shiqin; Fu, Ricky K.Y.; Chu, Paul K.

    2009-01-01

    The influence of radio-frequency (RF) power on the structure and gas permeation through amorphous hydrogenated carbon films deposited on cylindrical polyethylene terephthalate (PET) samples is investigated. The results show that a higher radio-frequency power leads to a smaller sp 3 /sp 2 value but produces fewer defects with smaller size. The permeability of PET samples decreases significantly after a-C:H deposition and the RF only exerts a small influence. However, the coating uniformity, color, and wettability of the surface are affected by the RF power. A higher RF power results in to better uniformity and it may be attributed to the combination of the high-density plasma and sample heating.

  13. Synthesis and Properties of High Strength Thin Film Composites of Poly(ethylene Oxide and PEO-PMMA Blend with Cetylpyridinium Chloride Modified Clay

    Directory of Open Access Journals (Sweden)

    Mohammad Saleem Khan

    2015-01-01

    Full Text Available Ion-conducting thin film composites of polymer electrolytes were prepared by mixing high MW poly(ethylene oxide (PEO, poly(methyl methacrylate (PMMA as a polymer matrix, cetylpyridinium chloride (CPC modified MMT as filler, and different content of LiClO4 by using solution cast method. The crystallinity, ionic conductivity (σ, and mechanical properties of the composite electrolytes and blend composites were evaluated by using XRD, AC impedance, and UTM studies, respectively. The modification of clay by CPC showed enhancement in the d-spacing. The loading of clay has effect on crystallinity of PEO systems. Blend composites showed better mechanical properties. Young’s modulus and elongation at break values showed increase with salt and clay incorporation in pure PEO. The optimum composition composite of PEO with 3.5 wt% of salt and 3.3 wt% of CPMMT exhibited better performance.

  14. Bilateral anterior thalamic low densities in descending transtentorial herniation

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, Chikao; Watanabe, Takao

    1985-02-01

    Round, well-demarcated, symmetrical low densities in a bilateral thalamus in a case of descending transtentorial herniation due secondarily to acute traumatic left subdural hematoma are reported. An 8-year-old boy, on whom emergency surgery was refused by his parents, showed a marked shift due to the hematoma on admission; this was followed by a low density in the left PCA territory and round, equivocal hypodensities in the anterior thalamus 44 hours post-trauma. The equivocal hypodensities became definite, well-demarcated, round low densities situated symmetrically in the anterior thalamus on the 39th day post-trauma. Akinetic mutism was noted at this time. The symmetrical low densities and the PCA-territory low density persisted as late as the 39th day post-trauma, suggesting infarcts. The downward stretch of the bilateral thalamoperforators, which was effected by a narrowing of the interpeduncular fossa with an approximation of the bilateral perforators, plus a downward shift of the PCA due to descending transtentorial herniation, was assumed to be the mechanism involved. (author).

  15. GREENHOUSE PLASTIC FILMS CAPABLE OF MODIFYING THE SPECTRAL DISTRIBUTION OF SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Evelia Schettini

    2010-03-01

    Full Text Available The aim of this paper was to investigate the radiometric properties of innovative covering films for protected cultivation capable of modifying the spectral distribution of the transmitted radiation and thus the vegetative activity. Two photoselective films, three photoluminescent films and one low-density polyethylene film were used as greenhouse coverings for cherry trees and peach trees, grown in pots. The photoselective films were characterised by a reduction of the R/FR ratio in comparison to the natural solar radiation. Tree growth parameters, such as the apical shoot of cherry trees and the shoot of peach trees, were monitored. Different responses to vegetative activities were observed under the films, depending on the species, with a higher shoots growth rate in the peach with respect to the cherry. The photoselective film characterised by the lowest R/FR ratio significantly enhanced the growth of cherry and peach trees in comparison to the trees cultivated under the other greenhouse films

  16. Clathrates and beyond: Low-density allotropy in crystalline silicon

    Energy Technology Data Exchange (ETDEWEB)

    Beekman, Matt [Department of Physics, California Polytechnic State University, San Luis Obispo, California 93407 (United States); Wei, Kaya; Nolas, George S., E-mail: gnolas@usf.edu [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States)

    2016-12-15

    In its common, thermodynamically stable state, silicon adopts the same crystal structure as diamond. Although only a few alternative allotropic structures have been discovered and studied over the past six decades, advanced methods for structure prediction have recently suggested a remarkably rich low-density phase space that has only begun to be explored. The electronic properties of these low-density allotropes of silicon, predicted by first-principles calculations, indicate that these materials could offer a pathway to improving performance and reducing cost in a variety of electronic and energy-related applications. In this focus review, we provide an introduction and overview of recent theoretical and experimental results related to low-density allotropes of silicon, highlighting the significant potential these materials may have for technological applications, provided substantial challenges to their experimental preparation can be overcome.

  17. Bilateral symmetrical low density areas in the basal ganglia

    International Nuclear Information System (INIS)

    Ugawa, Yoshikazu; Ihara, Yasuo

    1984-01-01

    We reported a case with dysarthria and gait disturbance, in which CT revealed symmetrical well-demarcated low density areas in the basal ganglia. The patient was a 43-year-old woman. Her family history and past history were not contributory. She had a little difficulty in speaking at the age of 17. Gait disturbance and micrographia appeared later. Although her expressionless face resembles to that seen in Parkinsonism, rigidity, akinesia and small-stepped gait were not present. The unclassified types of dysarthria and gait disturbance, which characterize the present case, were considered to be a kind of extrapyramidal symptoms, which were distinct from those of Parkinsonism. CT showed well demarcated low density areas predominantly in bilateral putamen. Metrizamide CT failed to show any communication between low density areas and subarachnoid spaces. To date, six cases, which presented similar clinical features and almost same CT findings as our case, were reported. (author)

  18. Parametric and mechanical characterization of linear low density ...

    Indian Academy of Sciences (India)

    characterization of the material is equally important in relation to quality and relia- ... be moulded as one single part (with no weld lines or joints), eliminating high .... mechanical analysis of three powders viz. polyethylene, polypropylene and ...

  19. Radiation modification and interaction mechanism of polypropylene and polyethylene by protons and electrons

    International Nuclear Information System (INIS)

    Wang Guanghou

    1988-10-01

    A systematic investigation of radiation effects on isotactic polypropylene (PP) and low-density polyethylene (PE) films by protons and electrons is reported. Electrons can make polyethylene cross-linked and polypropylene crached while protons can improve the PP mechanical properties and deteriorate polyethylene with increasing the irradiation dose. The structural analysis shows that conversion between α and β phases occurs and the crystallinity remains constant in the electron-irradiated polypropylene whereas the network structure is formed by allyl-type radicals in the e - -irradiated polyethylene. The infrared spectra indicate that conformational changes have taken place in the polypropylene under proton bombardment, such as the transition from an ordered to a disordered state in the crystalline region, the formation of double bonds as well as trans-conformations. This leads to the cross-linking between macromolecules of polypropylene at the proper irradiation doses, thus enhancing its mechanical properties. The cross-linking of polypropylene by proton bombardment observed and its properties may have some potential applications

  20. Developing and Evaluating Composites Based on Plantation Eucalyptus Rotary-cut Veneer and High-density Polyethylene Film as Novel Building Materials

    Directory of Open Access Journals (Sweden)

    Wei Song

    2016-02-01

    Full Text Available To achieve value-added utilizations of plantation timbers, eucalyptus veneer/high-density polyethylene film composites were prepared, with process-factors (PF (hot-pressing temperature, HT; hot-pressing duration, HD; hot-pressing pressure, HP; HDPE-film content, HC and composite-properties (CP (water-resistant bonding-strength, BS; modulus of rupture, MOR; modulus of elasticity, MOE investigated. According to thermal analyses, 140 to 180 °C was appropriate for HT. Based on statistical analyses, HD was easier to affect CP, while MOE was easier to be affected by PF. Quantitative relationships between PF and CP were determined by the neural-network (ANN modeling. In ANN simulation surveys, CP displayed Gaussian distributions (R2 > 0.9 when PF changed in current ranges, with positive correlations between BS and MOR (R2 ≈ 0.5. Combining ANN and the genetic-algorithm, optimal processes (HT, 160 °C; HD, 50 s/mm; HP, 1.3 MPa; HC, 6 layers were found, and optimal results (BS, 1.30 MPa; MOR, 86.94 MPa; MOE, 8.33 GPa were comparable to various reported poplar-plywoods. Microscopic images demonstrated that composite interfaces were formed by the mechanical interlocking. The optimal BS attained Chinese standards for water-resistant plywoods, so proposed composites can serve as water-resistant and formaldehyde-free building materials for furniture and interior design.

  1. Low-density lipoprotein cholesterol and risk of gallstone disease

    DEFF Research Database (Denmark)

    Stender, Stefan; Frikke-Schmidt, Ruth; Benn, Marianne

    2013-01-01

    Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone...

  2. Importing low-density ideas to high-density revitalisation

    DEFF Research Database (Denmark)

    Arnholtz, Jens; Ibsen, Christian Lyhne; Ibsen, Flemming

    2016-01-01

    Why did union officials from a high-union-density country like Denmark choose to import an organising strategy from low-density countries such as the US and the UK? Drawing on in-depth interviews with key union officials and internal documents, the authors of this article argue two key points. Fi...

  3. Increased oxidizability of low-density lipoproteins in hypothyroidism

    NARCIS (Netherlands)

    Diekman, T.; Demacker, P. N.; Kastelein, J. J.; Stalenhoef, A. F.; Wiersinga, W. M.

    1998-01-01

    Hypothyroidism leads to an increase of plasma low-density lipoprotein (LDL) cholesterol levels. Oxidation of LDL particles changes their intrinsic properties, thereby enhancing the development of atherosclerosis. T4 has three specific binding sites on apolipoprotein B; furthermore it inhibits LDL

  4. Role of oxidized low-density lipoprotein in renal disease

    NARCIS (Netherlands)

    Heeringa, P; Tervaert, JWC

    Accelerated atherosclerosis is often observed in patients with chronic renal failure. In the present review we summarize and discuss the recent literature on the pathogenic role of low-density lipoproteins modified by oxidative processes in atherosclerosis and the possible role in renal diseases.

  5. Three-dimensional structure of low-density nuclear matter

    International Nuclear Information System (INIS)

    Okamoto, Minoru; Maruyama, Toshiki; Yabana, Kazuhiro; Tatsumi, Toshitaka

    2012-01-01

    We numerically explore the pasta structures and properties of low-density nuclear matter without any assumption on the geometry. We observe conventional pasta structures, while a mixture of the pasta structures appears as a metastable state at some transient densities. We also discuss the lattice structure of droplets.

  6. Three-dimensional structure of low-density nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Minoru, E-mail: okamoto@nucl.ph.tsukuba.ac.jp [Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, Shirakata Shirane 2-4, Tokai, Ibaraki 319-1195 (Japan); Maruyama, Toshiki, E-mail: maruyama.toshiki@jaea.go.jp [Advanced Science Research Center, Japan Atomic Energy Agency, Shirakata Shirane 2-4, Tokai, Ibaraki 319-1195 (Japan); Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Yabana, Kazuhiro, E-mail: yabana@nucl.ph.tsukuba.ac.jp [Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Center of Computational Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Tatsumi, Toshitaka, E-mail: tatsumi@ruby.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2012-07-09

    We numerically explore the pasta structures and properties of low-density nuclear matter without any assumption on the geometry. We observe conventional pasta structures, while a mixture of the pasta structures appears as a metastable state at some transient densities. We also discuss the lattice structure of droplets.

  7. Plasma probe characteristics in low density hydrogen pulsed plasmas

    International Nuclear Information System (INIS)

    Astakhov, D I; Lee, C J; Bijkerk, F; Goedheer, W J; Ivanov, V V; Krivtsun, V M; Zotovich, A I; Zyryanov, S M; Lopaev, D V

    2015-01-01

    Probe theories are only applicable in the regime where the probe’s perturbation of the plasma can be neglected. However, it is not always possible to know, a priori, that a particular probe theory can be successfully applied, especially in low density plasmas. This is especially difficult in the case of transient, low density plasmas. Here, we applied probe diagnostics in combination with a 2D particle-in-cell model, to an experiment with a pulsed low density hydrogen plasma. The calculations took into account the full chamber geometry, including the plasma probe as an electrode in the chamber. It was found that the simulations reproduce the time evolution of the probe IV characteristics with good accuracy. The disagreement between the simulated and probe measured plasma density is attributed to the limited applicability of probe theory to measurements of low density pulsed plasmas on a similarly short time scale as investigated here. Indeed, in the case studied here, probe measurements would lead to, either a large overestimate, or underestimate of the plasma density, depending on the chosen probe theory. In contrast, the simulations of the plasma evolution and the probe characteristics do not suffer from such strict applicability limits. These studies show that probe theory cannot be justified through probe measurements. However, limiting cases of probe theories can be used to estimate upper and lower bounds on plasma densities. These theories include and neglect orbital motion, respectively, with different collisional terms leading to intermediate estimates. (paper)

  8. Human Low Density Lipoprotein as a Vehicle of Atherosclerosis ...

    African Journals Online (AJOL)

    Low-density lipoproteins have been sufficiently established as an important precursor of atherosclerosis. The actual mechanism is still unclear, and the current technique of using radioisotopes has clinical limitation. However, the current study techniques or methods excellently elucidate the functional aspects of ...

  9. 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)

    Hernandez, L.; Urena, F.; Lopez, R.

    1997-01-01

    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)

  10. Transparent Low Molecular Weight Poly(Ethylene Glycol Diacrylate-Based Hydrogels as Film Media for Photoswitchable Drugs

    Directory of Open Access Journals (Sweden)

    Théophile Pelras

    2017-11-01

    Full Text Available Hydrogels have shown a great potential as materials for drug delivery systems thanks to their usually excellent bio-compatibility and their ability to trap water-soluble organic molecules in a porous network. In this study, poly(ethylene glycol-based hydrogels containing a model dye were synthesized by ultraviolet (UV-A photopolymerization of low-molecular weight macro-monomers and the material properties (dye release ability, transparency, morphology, and polymerization kinetics were studied. Real-time infrared measurements revealed that the photopolymerization of the materials was strongly limited when the dye was added to the uncured formulation. Consequently, the procedure was adapted to allow for the formation of sufficiently cured gels that are able to capture and later on to release dye molecules in phosphate-buffered saline solution within a few hours. Due to the transparency of the materials in the 400–800 nm range, the hydrogels are suitable for the loading and excitation of photoactive molecules. These can be uptaken by and released from the polymer matrix. Therefore, such materials may find applications as cheap and tailored materials in photodynamic therapy (i.e., light-induced treatment of skin infections by bacteria, fungi, and viruses using photoactive drugs.

  11. 21 CFR 172.260 - Oxidized polyethylene.

    Science.gov (United States)

    2010-04-01

    ... to 19. (b) The additive is used or intended for use as a protective coating or component of protective coatings for fresh avocados, bananas, beets, coconuts, eggplant, garlic, grapefruit, lemons, limes... Coatings, Films and Related Substances § 172.260 Oxidized polyethylene. Oxidized polyethylene may be safely...

  12. Plasma parameters effects on the properties, aging and stability behaviors of allylamine plasma coated ultra-high molecular weight polyethylene (UHMWPE) films

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Gaelle, E-mail: gaelle.aziz@ugent.be; Thukkaram, Monica; De Geyter, Nathalie; Morent, Rino

    2017-07-01

    Highlights: • Medium to atmospheric pressure DBD is used to deposit amino rich films. • Process parameters affect the films’ surface chemical and physical properties. • High deposition rates can be reached by varying the power and/or monomer flow rate. • High amino selectivity (NH{sub 2}/N in %) is obtained at low powers and high monomer concentration. • Aging and stability behaviors of the deposited coatings can be controlled by carefully choosing the plasma parameters. - Abstract: In this work, a dielectric barrier discharge (DBD) operated at medium to atmospheric pressure has been used for the deposition of thin polyallylamine (PAA) films on ultra-high molecular weight polyethylene (UHMWPE) substrates. The effect of treatment time (1–5 min), discharge power (5.7–24.0 W), monomer concentration (1–2 g/h) and pressure (10–100 kPa) on the films properties, aging and stability behaviors have been investigated. The used characterization techniques are X-ray photoelectron spectroscopy, water contact angle and optical reflectance spectroscopy. In this paper, it is shown that plasma treatment time does not affect the coatings chemistry; whereas plasma power, monomer concentration and pressure control the coatings properties. It is also shown that the deposition rate of the deposited films changes with varying W/FM values. At low W/FM values, high deposition rates of up to 2 nm/s are observed. Plasma treatments were also characterized by their amino efficiency ([NH{sub 2}]/[C] in %) and amino selectivity ([NH{sub 2}]/[N] in %). Depending on the used parameters, these varied between 12.3% and 20% and between 71.2% and 91.1%, respectively. For the aging study, coatings that preserved most of their hydrophilicity were obtained at power ≤11.3 W, monomer concentration ≥1.5 g/h and pressure ≥50 kPa. For the stability study, coatings that showed the highest [N] (%) and lowest percentage of thickness decrease were obtained at ≤2 min, 24.0 W, 1 g/h and

  13. Electroless plating Cu-Co-P polyalloy on UV/ozonolysis irradiated polyethylene terephthalate film and its corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Lei; Bi, Siyi; Zhao, Hang; Xu, Yumeng; Mu, Yuhang; Lu, Yinxiang, E-mail: yxlu@fudan.edu.cn

    2017-05-01

    Highlights: • Electroless plating Cu-Co-P polyalloy was firstly fabricated onto polyethylene terephthalate (PET) substrate. • An etchant-free and amine-free UV/ozonolysis irradiation method UV/ozonolysis was effective for the transition from hydrophilic to hydrophobic of PET sheet. • A time-saving and cost-effective orthogonal experiment (L{sub 9}(3){sup 4}) was utilized to optimize the plating conditions. • The optimized copper polyalloy possessed high corrosion resistance in three aggressive mediums including NaCl, NaOH and HCl, respectively. • The Cu-Co-P coated PET composite showed excellent electromagnetic interference shielding effectiveness (EMI SE > 99.999% at frequency ranging from 30 MHz to 1000 MHz). - Abstract: High corrosion resistant Cu-Co-P coatings were firstly prepared on polyethylene terephthalate (PET) substrate by electroless plating in combination with UV/ozonolysis irradiation under optimized cobalt sulfate heptahydrate concentration, pH value, plating temperature and time. The copper polyalloy/PET composite can be obtained in three steps, namely: (i) the generation of oxygen-containing functionalities (carboxylic groups) onto PET surface through UV irradiation combined with ozone, (ii) Cu seeding catalysts were obtained after being immersed into cupric citrate and NaBH{sub 4} solutions subsequently, and (iii) Cu-Co-P polyalloy metallization using electroless plating bath. Attenuated total reflection fourier transformation infrared spectrometer (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), water contact angle measurement and energy dispersive X-ray analysis (EDAX) were utilized to track the surface changes during the whole process. The electroless plating conditions were optimized by an orthogonal experiment (L{sub 9}(3){sup 4}) for Cu-Co-P coating as follows: CoSO{sub 4}·7H{sub 2}O addition of 0.08 M, pH value, plating temperature and time were set on 10.0, 35 °C and 25 min, respectively. Under the optimal conditions, copper

  14. Temperature dependence of radiation effects in polyethylene

    International Nuclear Information System (INIS)

    Wu, G; Katsumura, Y.; Kudoh, H.; Morita, Y.; Seguchi, T.

    2000-01-01

    Temperature dependence of crosslinking and gas evolution under γ-irradiation was studied for high-density and low-density polyethylene samples in the 30-360degC range. It was found that crosslinking was the predominant process up to 300degC and the gel point decreased with increasing temperature. At above 300degC, however, the gel fraction at a given dose decreased rapidly with temperature and the action of radiation turned to enhance polyethylene degradation. Yields of H 2 and hydrocarbon gases increased with temperature and the compositions of hydrocarbons were dose dependent. (author)

  15. Diffuse Reflectance Spectroscopy of Hidden Objects, Part I: Interpretation of the Reflection-Absorption-Scattering Fractions in Near-Infrared (NIR) Spectra of Polyethylene Films.

    Science.gov (United States)

    Pomerantsev, Alexey L; Rodionova, Oxana Ye; Skvortsov, Alexej N

    2017-08-01

    Investigation of a sample covered by an interfering layer is required in many fields, e.g., for process control, biochemical analysis, and many other applications. This study is based on the analysis of spectra collected by near-infrared (NIR) diffuse reflectance spectroscopy. Each spectrum is a composition of a useful, target spectrum and a spectrum of an interfering layer. To recover the target spectrum, we suggest using a new phenomenological approach, which employs the multivariate curve resolution (MCR) method. In general terms, the problem is very complex. We start with a specific problem of analyzing a system, which consists of several layers of polyethylene (PE) film and underlayer samples with known spectral properties. To separate information originating from PE layers and the target, we modify the system versus both the number of the PE layers as well as the reflectance properties of the target sample. We consider that the interfering spectrum of the layer can be modeled using three components, which can be tentatively called transmission, absorption, and scattering contributions. The novelty of our approach is that we do not remove the reflectance and scattering effects from the spectra, but study them in detail aiming to use this information to recover the target spectrum.

  16. Formulation and in vitro characterization of novel sildenafil citrate-loaded polyvinyl alcohol-polyethylene glycol graft copolymer-based orally dissolving films.

    Science.gov (United States)

    Xu, Li-Li; Shi, Li-Li; Cao, Qing-Ri; Xu, Wei-Juan; Cao, Yue; Zhu, Xiao-Yin; Cui, Jing-Hao

    2014-10-01

    This work was aimed to develop novel sildenafil citrate (SC)-loaded polyvinyl alcohol (PVA)-polyethylene glycol (PEG) graft copolymer (Kollicoat(®) IR)-based orally dissolving films (ODFs) using a solvent casting method. Formulation factors such as plasticizers and disintegrants were optimized on the basis of characteristics of blank ODFs. The SC-loaded ODF with a loading capacity up to 6.25mg in an area of 6 cm(2) was prepared and evaluated in terms of mechanical properties, disintegration time and dissolution rate. The physicochemical properties of drug-loaded ODF were also investigated using the scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). The blank ODF composed of Kollicoat(®) IR, sodium alginate (ALG-Na) and glycerol (10:2:1.5, w/w) had a remarkably short disintegration time of about 20s. The SC-loaded ODF showed a delayed disintegration time (about 25s), but exhibited improved mechanical properties when compared to the blank ODF. SC was homogeneously dispersed throughout the ODF and the crystalline form of drug had been partly changed, existing strong hydrogen bonding between the drug and carriers. The Kollicoat(®) IR/ALG-Na based ODFs containing SC might be an alternative to conventional tablet for the treatment of male erectile dysfunction. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Simulation of synaptic short-term plasticity using Ba(CF3SO3)2-doped polyethylene oxide electrolyte film.

    Science.gov (United States)

    Chang, C T; Zeng, F; Li, X J; Dong, W S; Lu, S H; Gao, S; Pan, F

    2016-01-07

    The simulation of synaptic plasticity using new materials is critical in the study of brain-inspired computing. Devices composed of Ba(CF3SO3)2-doped polyethylene oxide (PEO) electrolyte film were fabricated and with pulse responses found to resemble the synaptic short-term plasticity (STP) of both short-term depression (STD) and short-term facilitation (STF) synapses. The values of the charge and discharge peaks of the pulse responses did not vary with input number when the pulse frequency was sufficiently low(~1 Hz). However, when the frequency was increased, the charge and discharge peaks decreased and increased, respectively, in gradual trends and approached stable values with respect to the input number. These stable values varied with the input frequency, which resulted in the depressed and potentiated weight modifications of the charge and discharge peaks, respectively. These electrical properties simulated the high and low band-pass filtering effects of STD and STF, respectively. The simulations were consistent with biological results and the corresponding biological parameters were successfully extracted. The study verified the feasibility of using organic electrolytes to mimic STP.

  18. Studies on Impingement Effects of Low Density Jets on Surfaces — Determination of Shear Stress and Normal Pressure

    Science.gov (United States)

    Sathian, Sarith. P.; Kurian, Job

    2005-05-01

    This paper presents the results of the Laser Reflection Method (LRM) for the determination of shear stress due to impingement of low-density free jets on flat plate. For thin oil film moving under the action of aerodynamic boundary layer the shear stress at the air-oil interface is equal to the shear stress between the surface and air. A direct and dynamic measurement of the oil film slope is measured using a position sensing detector (PSD). The thinning rate of oil film is directly measured which is the major advantage of the LRM over LISF method. From the oil film slope history, direct calculation of the shear stress is done using a three-point formula. For the full range of experiment conditions Knudsen numbers varied till the continuum limit of the transition regime. The shear stress values for low-density flows in the transition regime are thus obtained using LRM and the measured values of shear show fair agreement with those obtained by other methods. Results of the normal pressure measurements on a flat plate in low-density jets by using thermistors as pressure sensors are also presented in the paper. The normal pressure profiles obtained show the characteristic features of Newtonian impact theory for hypersonic flows.

  19. Development of Low Density, Flexible Carbon Phenolic Ablators

    Science.gov (United States)

    Stackpoole, Mairead; Thornton, Jeremy; Fan, Wendy; Covington, Alan; Doxtad, Evan; Beck, Robin; Gasch, Matt; Arnold, Jim

    2012-01-01

    Phenolic Impregnated Carbon Ablator (PICA) was the enabling TPS material for the Stardust mission where it was used as a single piece heatshield. PICA has the advantages of low density (approximately 0.27 grams per cubic centimeter) coupled with efficient ablative capability at high heat fluxes. Due to its brittle nature and low strain to failure recent efforts at NASA ARC have focused on alternative architectures to yield flexible and more conformal carbon phenolic materials with comparable densities to PICA. This presentation will discuss flexible alternatives to PICA and include preliminary mechanical and thermal properties as well as recent arc jet and LHMEL screening test results.

  20. Performance of Low-Density Parity-Check Coded Modulation

    Science.gov (United States)

    Hamkins, Jon

    2010-01-01

    This paper reports the simulated performance of each of the nine accumulate-repeat-4-jagged-accumulate (AR4JA) low-density parity-check (LDPC) codes [3] when used in conjunction with binary phase-shift-keying (BPSK), quadrature PSK (QPSK), 8-PSK, 16-ary amplitude PSK (16- APSK), and 32-APSK.We also report the performance under various mappings of bits to modulation symbols, 16-APSK and 32-APSK ring scalings, log-likelihood ratio (LLR) approximations, and decoder variations. One of the simple and well-performing LLR approximations can be expressed in a general equation that applies to all of the modulation types.

  1. Low density lipoprotein sensor based on surface plasmon resonance

    International Nuclear Information System (INIS)

    Matharu, Zimple; Sumana, G.; Pandey, M.K.; Gupta, Vinay; Malhotra, B.D.

    2009-01-01

    Biotinylated heparin has been immobilized onto self-assembled monolayer of 4-aminothiophenol using avidin-biotin specific binding. The modified electrodes have been characterized using surface plasmon resonance technique (SPR), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM) and contact angle (CA) measurements. The interaction of immobilized biotinylated heparin with low density lipoprotein (LDL) has been studied using surface plasmon resonance technique. The biotinylated heparin modified electrode can be used to detect LDL in the range of 20 to 100 mg/dl with the sensitivity of 513.3 m o /μM.

  2. Low density lipoprotein sensor based on surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Matharu, Zimple [Department of Science and Technology Centre on Biomolecular Electronics, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Department of Physics and Astrophysics, University of Delhi, New Delhi-110007 (India); Sumana, G.; Pandey, M.K. [Department of Science and Technology Centre on Biomolecular Electronics, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Gupta, Vinay [Department of Physics and Astrophysics, University of Delhi, New Delhi-110007 (India); Malhotra, B.D., E-mail: bansi.malhotra@gmail.co [Department of Science and Technology Centre on Biomolecular Electronics, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India)

    2009-11-30

    Biotinylated heparin has been immobilized onto self-assembled monolayer of 4-aminothiophenol using avidin-biotin specific binding. The modified electrodes have been characterized using surface plasmon resonance technique (SPR), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM) and contact angle (CA) measurements. The interaction of immobilized biotinylated heparin with low density lipoprotein (LDL) has been studied using surface plasmon resonance technique. The biotinylated heparin modified electrode can be used to detect LDL in the range of 20 to 100 mg/dl with the sensitivity of 513.3 m{sup o}/{mu}M.

  3. Flow visualization of a low density hypersonic flow field

    International Nuclear Information System (INIS)

    Masson, B.S.; Jumper, E.J.; Walters, E.; Segalman, T.Y.; Founds, N.D.

    1989-01-01

    Characteristics of laser induced iodine fluorescence (LIIF) in low density hypersonic flows are being investigated for use as a diagnostic technique. At low pressures, doppler broadening dominates the iodine absorption profile producing a fluorescence signal that is primarily temperature and velocity dependent. From this dependency, a low pressure flow field has the potential to be mapped for its velocity and temperature fields. The theory for relating iodine emission to the velocity and temperature fields of a hypersonic flow is discussed in this paper. Experimental observations are made of a fluorescencing free expansion and qualitatively related to the theory. 7 refs

  4. Low-density lipoproteins cause atherosclerotic cardiovascular disease

    DEFF Research Database (Denmark)

    Ference, Brian A.; Ginsberg, Henry N.; Graham, Ian

    2017-01-01

    Aims To appraise the clinical and genetic evidence that low-density lipoproteins (LDLs) cause atherosclerotic cardiovascular disease (ASCVD). Methods and results We assessed whether the association between LDL and ASCVD fulfils the criteria for causality by evaluating the totality of evidence from...... proportional to the absolute reduction in LDL-C and the cumulative duration of exposure to lower LDL-C, provided that the achieved reduction in LDL-C is concordant with the reduction in LDL particle number and that there are no competing deleterious off-target effects. Conclusion Consistent evidence from...

  5. Tissue response to intraperitoneal implants of polyethylene oxide-modified polyethylene terephthalate.

    Science.gov (United States)

    Desai, N P; Hubbell, J A

    1992-01-01

    Polyethylene terephthalate films surface modified with polyethylene oxide of mol wt 18,500 g/mol (18.5 k) by a previously described technique, were implanted in the peritoneal cavity of mice, along with their respective untreated controls, for periods of 1-28 d. The implants were retrieved and examined for tissue reactivity and cellular adherence. The control polyethylene terephthalate surfaces showed an initial inflammatory reaction followed by an extensive fibrotic response with a mean thickness of 60 microns at 28 d. By contrast, polyethylene oxide-modified polyethylene terephthalate showed only a mild inflammatory response and no fibrotic encapsulation throughout the implantation period: at 28 d a cellular monolayer was observed. Apparently either the polyethylene oxide-modified surface was stimulating less inflammation, which was in turn stimulating less fibroblastic overgrowth, or the cellular adhesion to the polyethylene oxide-modified surface was too weak to support cellular multilayers.

  6. Low density lipoproteins mediated nanoplatforms for cancer targeting

    International Nuclear Information System (INIS)

    Jain, Anupriya; Jain, Keerti; Kesharwani, Prashant; Jain, Narendra K.

    2013-01-01

    Chemotherapy is a foremost remedial approach for the treatment of localized and metastasized tumors. In order to explore new treatment modalities for cancer, it is important to identify qualitative or quantitative differences in metabolic processes between normal and malignant cells. One such difference may be that of increased receptor-mediated cellular uptake of low density lipoproteins (LDLs) by cancer cells. Lipoproteins in general and specifically LDL are ideal candidates for loading and delivering cancer therapeutic and diagnostic agents due to their biocompatibility. By mimicking the endogenous shape and structure of lipoproteins, the reconstituted lipoproteins can remain in circulation for an extended period of time, while largely evading the reticuloendothelial cells in the body’s defenses. In this account, we review the field of low density inspired nanoparticles in relation to the delivery of cancer imaging and therapeutic agents. LDL has instinctive cancer targeting potential and has been used to incorporate various lipophillic molecules to transport them to tumors. Nature’s method of rerouting LDL provides a strategy to extend the cancer targeting potential of lipoproteins far off its constricted purview. In this review, we have discussed the various aspects of LDL including its role in cancer imaging and chemotherapy in retrospect and prospect and current efforts aimed to further improve the delivery efficacy of LDL–drug complexes with reduced chances of drug resistance leading to optimal drug delivery. This review provides a strong support for the concept of using LDL as a drug carrier

  7. Low density lipoproteins mediated nanoplatforms for cancer targeting

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Anupriya; Jain, Keerti; Kesharwani, Prashant, E-mail: prashant_pharmacy04@rediffmail.com; Jain, Narendra K., E-mail: jnarendr@yahoo.co.in [Dr. H. S. Gour University, Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences (India)

    2013-09-15

    Chemotherapy is a foremost remedial approach for the treatment of localized and metastasized tumors. In order to explore new treatment modalities for cancer, it is important to identify qualitative or quantitative differences in metabolic processes between normal and malignant cells. One such difference may be that of increased receptor-mediated cellular uptake of low density lipoproteins (LDLs) by cancer cells. Lipoproteins in general and specifically LDL are ideal candidates for loading and delivering cancer therapeutic and diagnostic agents due to their biocompatibility. By mimicking the endogenous shape and structure of lipoproteins, the reconstituted lipoproteins can remain in circulation for an extended period of time, while largely evading the reticuloendothelial cells in the body's defenses. In this account, we review the field of low density inspired nanoparticles in relation to the delivery of cancer imaging and therapeutic agents. LDL has instinctive cancer targeting potential and has been used to incorporate various lipophillic molecules to transport them to tumors. Nature's method of rerouting LDL provides a strategy to extend the cancer targeting potential of lipoproteins far off its constricted purview. In this review, we have discussed the various aspects of LDL including its role in cancer imaging and chemotherapy in retrospect and prospect and current efforts aimed to further improve the delivery efficacy of LDL-drug complexes with reduced chances of drug resistance leading to optimal drug delivery. This review provides a strong support for the concept of using LDL as a drug carrier.

  8. Low density lipoproteins mediated nanoplatforms for cancer targeting

    Science.gov (United States)

    Jain, Anupriya; Jain, Keerti; Kesharwani, Prashant; Jain, Narendra K.

    2013-09-01

    Chemotherapy is a foremost remedial approach for the treatment of localized and metastasized tumors. In order to explore new treatment modalities for cancer, it is important to identify qualitative or quantitative differences in metabolic processes between normal and malignant cells. One such difference may be that of increased receptor-mediated cellular uptake of low density lipoproteins (LDLs) by cancer cells. Lipoproteins in general and specifically LDL are ideal candidates for loading and delivering cancer therapeutic and diagnostic agents due to their biocompatibility. By mimicking the endogenous shape and structure of lipoproteins, the reconstituted lipoproteins can remain in circulation for an extended period of time, while largely evading the reticuloendothelial cells in the body's defenses. In this account, we review the field of low density inspired nanoparticles in relation to the delivery of cancer imaging and therapeutic agents. LDL has instinctive cancer targeting potential and has been used to incorporate various lipophillic molecules to transport them to tumors. Nature's method of rerouting LDL provides a strategy to extend the cancer targeting potential of lipoproteins far off its constricted purview. In this review, we have discussed the various aspects of LDL including its role in cancer imaging and chemotherapy in retrospect and prospect and current efforts aimed to further improve the delivery efficacy of LDL-drug complexes with reduced chances of drug resistance leading to optimal drug delivery. This review provides a strong support for the concept of using LDL as a drug carrier.

  9. Effect of gamma irradiation on physico-mechanical properties of spice packaging films

    Energy Technology Data Exchange (ETDEWEB)

    Mizani, Maryam [Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, P.O. Box 14155-4933, Tehran (Iran, Islamic Republic of)], E-mail: mizani1_2000@yahoo.com; Sheikh, Nasrin [Nuclear Science and Technology Research Institute, Radiation Application Research School, P.O. Box 11365-3486, Tehran (Iran, Islamic Republic of); Ebrahimi, Samad N. [Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, P.O. Box 19835-389, Tehran (Iran, Islamic Republic of); Gerami, Abas [School of Mathematics, Statistics and Computer Science, University of Tehran, P.O. Box 14155-6455, Tehran (Iran, Islamic Republic of); Tavakoli, Farnaz A. [Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, P.O. Box 14155-4933, Tehran (Iran, Islamic Republic of)

    2009-09-15

    Physico-mechanical properties of two types of laminated films, commercially used for spice packaging, are investigated after gamma irradiation at 8, 10 and 15 kGy. Data showed that polyethylene terephthalate/polyethylene terephthalate/linear low density polyethylene (PET/PET/LLDPE) was more resistant to radiation compared to biaxially oriented polypropylene/cast polypropylene (BOPP/CPP) and its barrier properties slightly improved up to 15 kGy. Oxygen transmission rate of BOPP/CPP was increased by 25%, and the melting peak temperature was decreased by 3.9% at 15 kGy, which may lead to oxidation of packaged spices and loss of their aroma/flavour, respectively.

  10. Effect of gamma irradiation on physico-mechanical properties of spice packaging films

    International Nuclear Information System (INIS)

    Mizani, Maryam; Sheikh, Nasrin; Ebrahimi, Samad N.; Gerami, Abas; Tavakoli, Farnaz A.

    2009-01-01

    Physico-mechanical properties of two types of laminated films, commercially used for spice packaging, are investigated after gamma irradiation at 8, 10 and 15 kGy. Data showed that polyethylene terephthalate/polyethylene terephthalate/linear low density polyethylene (PET/PET/LLDPE) was more resistant to radiation compared to biaxially oriented polypropylene/cast polypropylene (BOPP/CPP) and its barrier properties slightly improved up to 15 kGy. Oxygen transmission rate of BOPP/CPP was increased by 25%, and the melting peak temperature was decreased by 3.9% at 15 kGy, which may lead to oxidation of packaged spices and loss of their aroma/flavour, respectively.

  11. Experimental Evidence of Low Density Liquid Water under Decompression

    Science.gov (United States)

    Shen, G.; Lin, C.; Sinogeikin, S. V.; Smith, J.

    2017-12-01

    Water is not only the most important substance for life, but also plays important roles in liquid science for its anomalous properties. It has been widely accepted that water's anomalies are not a result of simple thermal fluctuation, but are connected to the formation of various structural aggregates in the hydrogen bonding network. Among several proposed scenarios, one model of fluctuations between two different liquids has gradually gained traction. These two liquids are referred to as a low-density liquid (LDL) and a high-density liquid (HDL) with a coexistence line in the deeply supercooled regime at elevated pressure. The LDL-HDL transition ends with decreasing pressure at a liquid-liquid critical point (LLCP) with its Widom line extending to low pressures. Above the Widom line lies mostly HDL which is favored by entropy, while LDL, mostly lying below the Widom line, is favored by enthalpy in the tetrahedral hydrogen bonding network. The origin of water's anomalies can then be explained by the increase in structural fluctuations, as water is cooled down to deeply supercooled temperatures approaching the Widom line. Because both the LLCP and the LDL-HDL transition line lie in water's "no man's land" between the homogeneous nucleation temperature (TH, 232 K) and the crystallization temperature (TX, 150 K), the success of experiments exploring this region has been limited thus far. Using a rapid decompression technique integrated with in situ x-ray diffraction, we observe that a high-pressure ice phase transforms to a low-density noncrystalline (LDN) form upon rapid release of pressure at temperatures of 140-165K. The LDN subsequently crystallizes into ice-Ic through a diffusion-controlled process. The change in crystallization rate with temperature indicates that the LDN is a LDL with its tetrahedrally-coordinated network fully developed and clearly linked to low-density amorphous ices. The observation of the tetrahedral LDL supports the two-liquid model for

  12. Radiation effect on polyethylene tube operational properties

    International Nuclear Information System (INIS)

    Kagan, D.F.; Kantor, L.A.; Sokolov, I.A.; Pogrebetskij, G.E.; Perlova, N.A.; Chumakov, V.V.

    1975-01-01

    The operational properties (stability on prolonged usage and creeping) were determined for pressure pipes made of high-density and low-density polyethylene subjected to γ-radiation. The dependence of the period up to the breaking point on the radiation dosage was extreme in character, with a maximum being near 25 Mrad. With an increase in the irradiation dosage the character of the breaking changes from plastic (at 0-15 Mrad) to brittle (at higher dosages). The plots of creepage, indepent from the amount of radiation, can be described by logarithmic equation epsilon=epsilonsub(0)+K lgt (where, epsilon-deformation of creepage, %; epsilonsub(0)- and K - creepage constants). Therefore creepage can be considered as a criterion determining the carrying capacity of the γ-irradiated polyethylene. It was established that only radiation-grafted high-density polyethylene is suitable for hot water supply pipes

  13. Surface modification of polyethylene by diffuse barrier discharge plasma

    Czech Academy of Sciences Publication Activity Database

    Novák, I.; Števiar, M.; Popelka, A.; Chodák, I.; Mosnáček, J.; Špírková, Milena; Janigová, I.; Kleinová, A.; Sedliačik, J.; Šlouf, Miroslav

    2013-01-01

    Roč. 53, č. 3 (2013), s. 516-523 ISSN 0032-3888 R&D Projects: GA AV ČR(CZ) IAAX08240901 Institutional research plan: CEZ:AV0Z40500505 Keywords : low-density polyethylene * plasma discharge * surface modification Subject RIV: JI - Composite Materials Impact factor: 1.441, year: 2013

  14. Mechanical Properties of Low Density Alloys at Cryogenic Temperatures

    International Nuclear Information System (INIS)

    Jiao, X. D.; Liu, H. J.; Li, L. F.; Yang, K.

    2006-01-01

    Low-density alloys include aluminum alloys, titanium alloys and magnesium alloys. Aluminum alloys and titanium alloys have been widely investigated and used as structural materials for cryogenic applications because of their light weight and good low-temperature mechanical properties.For aerospace applications, persistent efforts are being devoted to reducing weight and improving performance. Magnesium alloys are the lightest structural alloys among those mentioned above. Therefore, it is necessary to pay attention to magnesium alloys and to investigate their behaviors at cryogenic temperatures. In this paper, we have investigated the mechanical properties and microstructures of some magnesium alloys at cryogenic temperatures. Experimental results on both titanium and magnesium alloys are taken into account in considering these materials for space application

  15. Elliptic flow from Coulomb interaction and low density elastic scattering

    Science.gov (United States)

    Sun, Yuliang; Li, Qingfeng; Wang, Fuqiang

    2018-04-01

    In high energy heavy ion collisions and interacting cold atom systems, large elliptic flow anisotropies have been observed. For the large opacity (ρ σ L ˜103 ) of the latter hydrodynamics is a natural consequence, but for the small opacity (ρ σ L ˜1 ) of the former the hydrodynamic description is questionable. To shed light onto the situation, we simulate the expansion of a low density argon ion (or atom) system, initially trapped in an elliptical region, under the Coulomb interaction (or elastic scattering). Significant elliptic anisotropy is found in both cases, and the anisotropy depends on the initial spatial eccentricity and the density of the system. The results may provide insights into the physics of anisotropic flow in high energy heavy ion collisions and its role in the study of quantum chromodynamics.

  16. Low density lipoprotein receptors: preliminary results on 'in vivo' study

    International Nuclear Information System (INIS)

    Lupattelli, G.; Virgolini, I.; Li, S.R.; Sinzinger, H.

    1991-01-01

    Plasmatic levels of low density lipoproteins (LDL) are regulated by the receptor pathway and most LDL receptor are located in the liver. A receptor defect due to genetic mutations of the LDL receptor gene is the cause of familial hypercholesterolemia (F.H.), a disease characterized by high cholesterol levels and premature atherosclerosis. Injections of autologous radiolabelled LDL, followed by hepatic scintiscanning, can be used to obtain 'in vivo' quantification of hepatic receptor activity, both in normal and hypercholesterolemic patients. In this study we observe no hepatic increase of radioactivity in patients affected by F.H., confirming the liver receptor defect. Scintigraphy is a non-invasive technique which can be used to diagnose this disease and to monitor the efficiacy of hypolipidemic therapy. (Authors)

  17. Statistical mechanics of low-density parity-check codes

    Energy Technology Data Exchange (ETDEWEB)

    Kabashima, Yoshiyuki [Department of Computational Intelligence and Systems Science, Tokyo Institute of Technology, Yokohama 2268502 (Japan); Saad, David [Neural Computing Research Group, Aston University, Birmingham B4 7ET (United Kingdom)

    2004-02-13

    We review recent theoretical progress on the statistical mechanics of error correcting codes, focusing on low-density parity-check (LDPC) codes in general, and on Gallager and MacKay-Neal codes in particular. By exploiting the relation between LDPC codes and Ising spin systems with multi-spin interactions, one can carry out a statistical mechanics based analysis that determines the practical and theoretical limitations of various code constructions, corresponding to dynamical and thermodynamical transitions, respectively, as well as the behaviour of error-exponents averaged over the corresponding code ensemble as a function of channel noise. We also contrast the results obtained using methods of statistical mechanics with those derived in the information theory literature, and show how these methods can be generalized to include other channel types and related communication problems. (topical review)

  18. Ballistics considerations for small-caliber, low-density projectiles

    International Nuclear Information System (INIS)

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.

    1993-01-01

    One major application for single- and two-stage light gas guns is for fueling magnetic fusion confinement devices. Powder guns are not a feasible alternative due to possible plasma contamination by residual powder gases and the eventual requirement of steady-state operation at ∼ 1 Hz, which will dictate a closed gas handling system where propellant gases are recovered, processed and recompressed. Interior ballistic calculations for single-stage light gas guns, both analytical and numerical, are compared to an extensive data base for low density hydrogenic projectiles (pellets). Some innovative range diagnostics are described for determining the size and velocity of these small (several mm) size projectiles. A conceptual design of a closed cycle propellant gas system is presented including tradeoffs between different light propellant gases

  19. Statistical mechanics of low-density parity-check codes

    International Nuclear Information System (INIS)

    Kabashima, Yoshiyuki; Saad, David

    2004-01-01

    We review recent theoretical progress on the statistical mechanics of error correcting codes, focusing on low-density parity-check (LDPC) codes in general, and on Gallager and MacKay-Neal codes in particular. By exploiting the relation between LDPC codes and Ising spin systems with multi-spin interactions, one can carry out a statistical mechanics based analysis that determines the practical and theoretical limitations of various code constructions, corresponding to dynamical and thermodynamical transitions, respectively, as well as the behaviour of error-exponents averaged over the corresponding code ensemble as a function of channel noise. We also contrast the results obtained using methods of statistical mechanics with those derived in the information theory literature, and show how these methods can be generalized to include other channel types and related communication problems. (topical review)

  20. KEPLER-7b: A TRANSITING PLANET WITH UNUSUALLY LOW DENSITY

    International Nuclear Information System (INIS)

    Latham, David W.; Buchhave, Lars A.; Furesz, Gabor; Geary, John C.; Borucki, William J.; Koch, David G.; Lissauer, Jack J.; Rowe, Jason F.; Brown, Timothy M.; Basri, Gibor; Batalha, Natalie M.; Caldwell, Douglas A.; Jenkins, Jon M.; Cochran, William D.; Dunham, Edward W.; Gautier, Thomas N.; Gilliland, Ronald L.; Howell, Steve B.; Marcy, Geoffrey W.; Monet, David G.

    2010-01-01

    We report on the discovery and confirmation of Kepler-7b, a transiting planet with unusually low density. The mass is less than half that of Jupiter, M P = 0.43 M J , but the radius is 50% larger, R P = 1.48 R J . The resulting density, ρ P = 0.17 g cm -3 , is the second lowest reported so far for an extrasolar planet. The orbital period is fairly long, P = 4.886 days, and the host star is not much hotter than the Sun, T eff = 6000 K. However, it is more massive and considerably larger than the Sun, M * = 1.35 M sun and R * = 1.84 R sun , and must be near the end of its life on the main sequence.

  1. Oxidized low-density lipoprotein in postmenopausal women

    DEFF Research Database (Denmark)

    Jankowski, Vera; Just, Alexander R; Pfeilschifter, Johannes

    2014-01-01

    BACKGROUND: Oxidized low-density lipoprotein (oxLDL) leads to atherosclerosis and cardiovascular disease, the most frequent causes of death worldwide. After menopause, lipid and lipoprotein metabolism changes and women are at greater risk of cardiovascular disease compared to fertile women. The aim.......10-0.43). Although intima-media thickness did not differ, postmenopausal women with serous oxLDL had more often atherosclerotic plaques compared to women without oxLDL (6/66 vs. 0/467; P lipoprotein, impaired glucose intolerance, and DBP were independently associated...... with the occurrence of oxLDL. If oxLDL was present, higher high-density lipoprotein and glucose intolerance were associated with higher concentrations of oxLDL. In contrast, higher blood urea concentrations were associated with lower concentrations of oxLDL. CONCLUSION: This study presents the prevalence...

  2. An empirical probability model of detecting species at low densities.

    Science.gov (United States)

    Delaney, David G; Leung, Brian

    2010-06-01

    False negatives, not detecting things that are actually present, are an important but understudied problem. False negatives are the result of our inability to perfectly detect species, especially those at low density such as endangered species or newly arriving introduced species. They reduce our ability to interpret presence-absence survey data and make sound management decisions (e.g., rapid response). To reduce the probability of false negatives, we need to compare the efficacy and sensitivity of different sampling approaches and quantify an unbiased estimate of the probability of detection. We conducted field experiments in the intertidal zone of New England and New York to test the sensitivity of two sampling approaches (quadrat vs. total area search, TAS), given different target characteristics (mobile vs. sessile). Using logistic regression we built detection curves for each sampling approach that related the sampling intensity and the density of targets to the probability of detection. The TAS approach reduced the probability of false negatives and detected targets faster than the quadrat approach. Mobility of targets increased the time to detection but did not affect detection success. Finally, we interpreted two years of presence-absence data on the distribution of the Asian shore crab (Hemigrapsus sanguineus) in New England and New York, using our probability model for false negatives. The type of experimental approach in this paper can help to reduce false negatives and increase our ability to detect species at low densities by refining sampling approaches, which can guide conservation strategies and management decisions in various areas of ecology such as conservation biology and invasion ecology.

  3. Field emission properties of low-density carbon nanotubes prepared on anodic aluminum-oxide template

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Soo-Hwan [Samsung Advanced Institute of Technology, Suwon (Korea, Republic of); Lee, Kun-Hong [Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2004-08-15

    Anodic aluminum-oxide (AAO) templates were fabricated by two-step anodizing an Al film. After the Co catalyst had been electrochemically deposited onto the bottom of the AAO template, carbon nanotubes (CNTs) were grown by using catalytic pyrolysis of C{sub 2}H{sub 2} and H{sub 2} at 650 .deg. C. Overgrowth of CNTs with low density on the AAO templates was observed. The field-emission measurements on the samples showed a turn-on field of 2.17 V/mum and a field enhancement factor of 5700. The emission pattern on a phosphor screen was quite homogeneous over the area at a relatively low electric field.

  4. Effect of tocopherols incorporation on physical properties of LDPE,PP and blend film of LDPE/PP

    Directory of Open Access Journals (Sweden)

    ZHU Xuntao

    2014-12-01

    Full Text Available The objectives of this study were to investigate the effects of added tocopherols and blending of different polymers on the film physical properties.Tocopherols (3 000 mg/kg were incorporate into low density polyethylene (LDPE,polypropylene (PP and a blend film of LDPE/PP (50/50 by extrusion process.Then films were evaluated to determine tocopherol recovery and physical properties.Results showed that extrusion did not significantly change film thermal properties (Tm,Tc and Tg as compared with synthetic polymer resin pellet (raw material.LDPE and PP did not seem to react with each other to form new polymers under the current extrusion conditions.Addition of tocopherol significantly changed film mechanical properties compared with control.The above results and other data seemed to support that polymer blending is a feasible approach for producing tocopherol containing packaging films.

  5. The overall heat transfer of greenhouses covered with PE [polyethylene film] and PVC [polyvinyl chloride film] single layer: The heat insulation efficiency of greenhouses and their covering materials (1)

    International Nuclear Information System (INIS)

    Minagawa, H.; Tachibana, K.

    1982-01-01

    Overall heat transfer of polyethylene film (PE) and polyvinyl chloride film (PVC) were measured in the experimental greenhouses with hot-air heaters on the clear and on the cloudy nights during the period Nov. 1979 to Jan. 1980. Both films are 0.1 mm thick and have different physical properties for long-wave radiation. The heat insulation efficiency of the greenhouses covered with PE and PVC single layer was investigated, and the ratio of floor area to covering area for the experimental greenhouses, which is one of the indices for the heat insulation efficiency of greenhouses, was also taken into consideration. The results are as follows: 1. Using the ratio of the overall heat transfer and the overall heat transfer coefficients for the heat insulation efficiency, the PE-house revealed to be less efficient than the PVC-house. This can be due to PE being more transparent to long-wave radiation than PVC. The advantage in the PVC-house, however, decreased with the increasing of the inside-outside air temperature difference (Figs. 3 and 5). 2. The overall heat transfer coefficients of both greenhouses depended on the inside-outside temperature difference. As the temperature difference increased, the overall heat transfer coefficients decreased (Fig. 5). 3. The overall heat transfer coefficients of both greenhouses were smaller on the cloudy nights than that on the clear nights. When the condensation occurred at the interior film surface, the heat insulation efficiency of both greenhouses was increased, resulting in the decrease of the coefficient. The efficiency of the PE-house was more affected than the PVC-house when the condensation occurred (Figs. 6 and 7). 4. When the inside-outside air temperature difference was small, convective heat transferred from the outside air to the outside cover surface. With an increase in the inside-outside air temperature difference, convective heat flow occurred from the outside cover surface to the outside air. This phenomenon was

  6. Protective properties of radiation-modified polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Surnina, N.N.; Saltykova, L.A.; Strochkova, E.M.; Tatarenko, O.F.

    1986-09-01

    A study was made of the mass transfer of corrosive liquids and gases through polyethylene films modified by radiation surface grafting. Studies were performed on an unstabilized type A film with graft adhesion-active layer based on polymethacrylic acid. The protective properties of the polymer coating in corrosive fluids with low vapor tension were estimated by impedance measurements. Steel specimens with a protective coating of radiation-modified polyethylene film were exposed to 10% sulfuric acid at room temperature. The results indicated that the acid did not penetrate through to the metal surface. The films retain their protective properties and protect the metal from the acid. Radiation modification significantly improves the adhesion of polyethylene to metals without reducing physical and mechanical properties of the polymers. 50 references, 1 figure.

  7. Bilateral symmetrical low density areas in the striatum

    International Nuclear Information System (INIS)

    Okabe, Ichiro; Shimoizumi, Hideo; Miyao, Masutomo; Kamoshita, Shigehiko

    1986-01-01

    A 10-year-old boy, who showed low density areas at bilateral striatal portion on brain CT, was reported. Characteristic clinical features were summarized as follows: 1. Onset in childhood (3 years old), 2. gait disturbance, dysarthria, involuntaly movement such as choreoathetosis and dystonia, 3. mild mental retardation (IQ 70), and 4. slowly progressive course over several years. Family history was unremarkable. His parents were not consanguineous. He was well until 3 years old, when he developed gait disturbance. At the age of 4, CT showed hypodensity lesions in the bilateral putamens, and right caudate was involved at 7, followed by bilateral caudate involvements at 10. Laboratory findings including blood lactate, pyruvate, serum copper, ceruloplasmin, aminoacids, urine and CSF catecholamines were within normal limits. TRH and thiamine therapies were ineffective L-dopa was slightly effective in movements, but symptoms were slowly progressive. We reviewed fourteen reported cases which were similar to our case in their onset, symptoms, clinical course and CT findings. Although the etiology was unknown, this case is possibly a new disease entity. (author)

  8. Morphology of Burned Ultra-low Density Fiberboards

    Directory of Open Access Journals (Sweden)

    Min Niu

    2015-09-01

    Full Text Available The synergistic effect of two fire retardants, a Si-Al compound and chlorinated paraffin, was tested on ultra-low density fiberboards (ULDFs. To further understand the mechanism of fire retardancy, morphologies of unburned and burned ULDFs were studied using a scanning electron microscope with energy dispersive spectroscopy. It was found that as the volume of the burned ULDFs shrank, some crevices appeared. In addition, less fly ash formed on the top of specimens, and more bottom ashes remained in the original framework, with a clear network of structure built by the fibers. Carbon was almost absent in the fly ash; however, the weight ratio of C in the bottom ashes reached the maximum (> 43% of the composition. Oxygen, Al, and Si appeared to have varying weight ratios for different ashes. Oxygen content increased with increasing Si and Al contents. Furthermore, Cl sharply decreased to less than 1% after combustion. Therefore, upon combustion, it was found that almost all of the substances in ULDFs, except for the Si-Al compound, were pyrolyzed to volatile carbon oxides and Cl compounds, especially the fly ash and lightweight C compounds.

  9. Low-density carbonized resorcinol-formaldehyde foams

    International Nuclear Information System (INIS)

    Kong, F.M.; Buckley, S.R.; Giles, C.L. Jr.; Haendler, B.L.; Hair, L.M.; Letts, S.A.; Overturf, G.E. III; Price, C.W.; Cook, R.C.

    1991-01-01

    This report documents research and development on resorcinol- formaldehyde-based foam materials conducted between 1986 and June 1990, when the effort was discontinued. The foams discussed are resorcinol-formaldehyde (RF) foam, carbonized RF (CRF) foam, and two composite foams, a polystyrene/RF (PS/RF) foam and its carbonized derivative (CPR). The RF foams are synthesized by the polycondensation of resorcinol with formaldehyde in a slightly basic solution. Their structure and density depend strongly on the concentration of the sodium carbonate catalyst. The have an interconnected bead structure similar to that of silica aerogels; bead sizes range from 30 to 130 Angstrom, and cell sizes are less than 0.1 μm. We have achieved densities of 16 to 200 mg/cm 3 . The RF foams can be pyrolyzed in an inert atmosphere to form a vitreous carbon foam (CRF), which has a similar microstructure but much higher mechanical strength. The PS/RF foams are obtained by filling the 2- to 3-μm cells of PS foam (a low-density hydrocarbon foam we have developed) with RF. The resultant foams have the outstanding handling and machinability of the PS foam matrix and the small cell size of RF. Pyrolyzing PS/RF foams causes depolymerization and loss of the PS; the resulting CPR foams have a structure similar to the PS foams in which CRF both replicates and fills the PS cells

  10. DAQ system for low density plasma parameters measurement

    International Nuclear Information System (INIS)

    Joshi, Rashmi S.; Gupta, Suryakant B.

    2015-01-01

    In various cases where low density plasmas (number density ranges from 1E4 to 1E6 cm -3 ) exist for example, basic plasma studies or LEO space environment measurement of plasma parameters becomes very critical. Conventional tip (cylindrical) Langmuir probes often result into unstable measurements in such lower density plasma. Due to larger surface area, a spherical Langmuir probe is used to measure such lower plasma densities. Applying a sweep voltage signal to the probe and measuring current values corresponding to these voltages gives V-I characteristics of plasma which can be plotted on a digital storage oscilloscope. This plot is analyzed for calculating various plasma parameters. The aim of this paper is to measure plasma parameters using a spherical Langmuir probe and indigenously developed DAQ system. DAQ system consists of Keithley source-meter and a host system connected by a GPIB interface. An online plasma parameter diagnostic system is developed for measuring plasma properties for non-thermal plasma in vacuum. An algorithm is developed using LabVIEW platform. V-I characteristics of plasma are plotted with respect to different filament current values and different locations of Langmuir probe with reference to plasma source. V-I characteristics is also plotted for forward and reverse voltage sweep generated programmatically from the source meter. (author)

  11. Surface determinants of low density lipoprotein uptake by endothelial cells

    International Nuclear Information System (INIS)

    Goeroeg, P.; Pearson, J.D.

    1984-01-01

    The surface sialic acid content of aortic endothelial cells in vitro was substantially lower in sparse cultures than at confluence. Binding of LDL to endothelial cells did not change at different culture densities and was unaffected by brief pretreatment with neuraminidase to partially remove surface sialic acid residues. In contrast, internalisation of LDL declined by a factor of 3 between low density cell cultures and confluent monolayers; neuraminidase pretreatment increased LDL uptake and the effect was most marked (>10-fold) at confluence. Pretreatment with cationised ferritin, which removed most of the surface sialic acid residues as well as glycosaminoglycans, increased LDL internalisation by up to 20-fold, again with most effect on confluent monolayers. Thus LDL uptake is inversely correlated with sialic acid content. We conclude that changes in the surface density of sialic acid (and possibly other charged) residues significantly modulate endothelial LDL uptake, and suggest that focal increases in LDL accumulation during atherogenesis may be related to alterations in endothelial endocytic properties at sites of increased cell turnover or damage. (author)

  12. Simulated Tip Rub Testing of Low-Density Metal Foam

    Science.gov (United States)

    Bowman, Cheryl L.; Jones, Michael G.

    2009-01-01

    Preliminary acoustic studies have indicated that low-density, open-cell, metal foams may be suitable acoustic liner material for noise suppression in high by-pass engines. Metal foam response under simulated tip rub conditions was studied to assess whether its durability would be sufficient for the foam to serve both as a rub strip above the rotor as well as an acoustic treatment. Samples represented four metal alloys, nominal cell dimensions ranging from 60 to 120 cells per inch (cpi), and relative densities ranging from 3.4 to 10 percent. The resulting rubbed surfaces were relatively smooth and the open cell structure of the foam was not adversely affected. Sample relative density appeared to have significant influence on the forces induced by the rub event. Acoustic responses of various surface preparations were measured using a normal incidence tube. The results of this study indicate that the foam s open-cell structure was retained after rubbing and that the acoustic absorption spectra variation was minimal.

  13. Direct numerical simulation of axisymmetric laminar low-density jets

    Science.gov (United States)

    Gomez Lendinez, Daniel; Coenen, Wilfried; Sevilla, Alejandro

    2017-11-01

    The stability of submerged laminar axisymmetric low-density jets has been investigated experimentally (Kyle & Sreenivasan 1993, Hallberg & Strykowski 2006) and with linear analysis (Jendoubi & Strykowski 1994, Coenen & Sevilla 2012, Coenen et al. 2017). These jets become globally unstable when the Reynolds number is larger than a certain critical value which depends on the density ratio and on the velocity profile at the injector outlet. In this work, Direct Numerical Simulations using FreeFEM + + (Hecht 2012) with P1 elements for pressure and P2 for velocity and density are performed to complement the above mentioned studies. Density and velocity fields are analyzed at long time showing the unforced space-time evolution of nonlinear disturbances propagating along the jet. Using the Stuart-Landau model to fit the numerical results for the self-excited oscillations we have computed a neutral stability curve that shows good agreement with experiments and stability theory. Thanks to Spanish MINECO under projects DPI2014-59292-C3-1-P and DPI2015-71901-REDT for financial support.

  14. Low density molecular cloud in the vicinity of the Pleiades

    International Nuclear Information System (INIS)

    Federman, S.R.; Wilson, R.F.

    1984-01-01

    The central region of a small, low density molecular cloud, which lies to the south of the Pleiades cluster, has been studied through the use of molecular line observations. Column densities for CH, OH, 12 CO, and 13 CO are derived from the radio data. The CH and OH data yield a visual extinction through the center of the cloud of about 3 mag. The ratio of the antenna temperatures for the OH main lines is consistent with optically thin emission; therefore, the OH results are a good indication of the total extinction through the optically thin emission; therefore, the OH results are a good indication of the total extinction through the cloud. The analysis of the carbon monoxide data produces a relatively high kinetic temperature of at least 20 K, a low total gas density of approx.300-500 cm -3 , and a column density of approx.4 x 10 17 cm -2 for 12 CO. Thus this small molecular cloud is not typical of the molecular material generally studied in Taurus

  15. Aggregation and fusion of modified low density lipoprotein.

    Science.gov (United States)

    Pentikäinen, M O; Lehtonen, E M; Kovanen, P T

    1996-12-01

    In atherogenesis, low density lipoprotein (LDL, diameter 22 nm) accumulates in the extracellular space of the arterial intima in the form of aggregates of lipid droplets (droplet diameter up to 400 nm). Here we studied the effects of various established in vitro LDL modifications on LDL aggregation and fusion. LDL was subjected to vortexing, oxidation by copper ions, proteolysis by alpha-chymotrypsin, lipolysis by sphingomyelinase, and nonenzymatic glycosylation, and was induced to form adducts with malondialdehyde or complexes with anti-apoB-100 antibodies. To assess the amount of enlarged LDL-derived structures formed (due to aggregation or fusion), we measured the turbidity of solutions containing modified LDL, and quantified the proportion of modified LDL that 1) sedimented at low-speed centrifugation (14,000 g), 2) floated at an increased rate at high-speed centrifugation (rate zonal flotation at 285,000 gmax), 3) were excluded in size-exclusion column chromatography (exclusion limit 40 MDa), or 4) failed to enter into 0.5%. Fast Lane agarose gel during electrophoresis. To detect whether particle fusion had contributed to the formation of the enlarged LDL-derived structures, particle morphology was examined using negative staining and thin-section transmission electron microscopy. We found that 1) aggregation was induced by the formation of LDL-antibody complexes, malondialdehyde treatment, and glycosylation of LDL; 2) fusion of LDL was induced by proteolysis of LDL by alpha-chymotrypsin; and 3) aggregation and fusion of LDL were induced by vortexing, oxidation by copper ions, and lipolysis by sphingomyclinase of LDL. The various modifications of LDL differed in their ability to induce aggregation and fusion.

  16. Measurement of radon permeability through polyethylene membrane using scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ashry, A.H.; Abou-Leila, M. [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Abdalla, A.M., E-mail: aymanabdalla62@hotmail.co [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Department of Physics, Faculty of Sciences and Arts, Najran University, Najran, P.O. Box. 11001 (Saudi Arabia); Advanced Materials and Nano-Engineering Laboratory (AMNEL), Centre for Advanced Materials and Nano-Engineering (CAMNE), Najran University, Najran, P.O. Box. 11001 (Saudi Arabia)

    2011-01-15

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211]method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  17. Measurement of radon permeability through polyethylene membrane using scintillation detector

    International Nuclear Information System (INIS)

    Ashry, A.H.; Abou-Leila, M.; Abdalla, A.M.

    2011-01-01

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211] method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  18. Determination of radiolysis products in gamma-irradiated multilayer barrier food packaging films containing a middle layer of recycled LDPE

    International Nuclear Information System (INIS)

    Chytiri, Stavroula; Goulas, Antonios E.; Badeka, Anastasia; Riganakos, Kyriakos A.; Petridis, Dimitrios; Kontominas, Michael G.

    2008-01-01

    Volatile and non-volatile radiolysis products and sensory changes of five-layer food packaging films have been determined after gamma irradiation (5-60 kGy). Barrier films were based on polyamide (PA) and low-density polyethylene (LDPE). Each film contained a middle buried layer of recycled LDPE or 100% virgin LDPE (control samples). Data showed that a large number of radiolysis products were produced such as hydrocarbons, alcohols, carbonyl compounds, carboxylic acid. These compounds were detected in the food simulant after contact with all films even at the lower absorbed doses of 5 and 10 kGy. The type and concentration of radiolysis products increased progressively with radiation dose, while no new compounds were detected as a result of the presence of recycled LDPE. In addition, irradiation dose appears to influence the sensory properties of table water in contact with films

  19. Combining Ratio Estimation for Low Density Parity Check (LDPC) Coding

    Science.gov (United States)

    Mahmoud, Saad; Hi, Jianjun

    2012-01-01

    The Low Density Parity Check (LDPC) Code decoding algorithm make use of a scaled receive signal derived from maximizing the log-likelihood ratio of the received signal. The scaling factor (often called the combining ratio) in an AWGN channel is a ratio between signal amplitude and noise variance. Accurately estimating this ratio has shown as much as 0.6 dB decoding performance gain. This presentation briefly describes three methods for estimating the combining ratio: a Pilot-Guided estimation method, a Blind estimation method, and a Simulation-Based Look-Up table. The Pilot Guided Estimation method has shown that the maximum likelihood estimates of signal amplitude is the mean inner product of the received sequence and the known sequence, the attached synchronization marker (ASM) , and signal variance is the difference of the mean of the squared received sequence and the square of the signal amplitude. This method has the advantage of simplicity at the expense of latency since several frames worth of ASMs. The Blind estimation method s maximum likelihood estimator is the average of the product of the received signal with the hyperbolic tangent of the product combining ratio and the received signal. The root of this equation can be determined by an iterative binary search between 0 and 1 after normalizing the received sequence. This method has the benefit of requiring one frame of data to estimate the combining ratio which is good for faster changing channels compared to the previous method, however it is computationally expensive. The final method uses a look-up table based on prior simulated results to determine signal amplitude and noise variance. In this method the received mean signal strength is controlled to a constant soft decision value. The magnitude of the deviation is averaged over a predetermined number of samples. This value is referenced in a look up table to determine the combining ratio that prior simulation associated with the average magnitude of

  20. Modification of low-density lipoprotein by different radioiodination methods

    International Nuclear Information System (INIS)

    Sobal, G.; Resch, U.; Sinzinger, H.

    2004-01-01

    Scintigraphic imaging of radiolabeled low-density lipoproteins (LDL) is an interesting tool for the understanding of its role in pathomechanism of atherosclerosis. Metabolism of native LDL shows quite different pattern and kinetics as compared to that of modified LDL which is not mediated by classical LDL-receptor and accumulates in atherosclerotic lesions to form lipid-laden foam cells. Therefore we were interested whether radiolabelling of LDL induces structural modifications. We performed the iodine labeling of LDL for scintigraphic imaging of atherosclerosis by three different methods: chloramine-T (A), iodine monochloride (B) and iodogen (C). The highest radiolabelling yield of 125 I was obtained by the iodogen method (75.44±13.52%) and the lowest (49.01±12.74%) by iodine monochloride. Chloramine T showed a labeling yield of 62.82±6.17%. The stability of the tracer was very high with all the methods, persisting up to 6 h (98.83±1.2% - 91.38±4.7%, 15 min vs 6 h after labeling). For the first time we not only investigated the influence of radiolabelling on relative electrophoretic mobility (REM), but also various oxidation parameters such as baseline dienes (BD), thiobarbituric acid reactive substances (TBARS), endogenous peroxides (POX) and oxidation resistance in the copper-mediated oxidation system (expressed as lag-time) were measured. Furthermore, oxidation- derived fragmentation of the lipoproteins was examined with SDS-PAGE electrophoresis. Data are expressed as % change compared to native LDL before radiolabeling. BD were reduced by 32% using the method (A), but increased by 33% and 47% with the monochloride (B) and iodogen method (C), respectively. The effect on lag-time was comparable for all the three methods, ranging from 25 to 36% reduction in lag-time. TBARS were strongly increased 5-7 fold by all the methods. REM was changed by all three methods. While by methods A and C we have found a moderate increase in REM by 1.75 and 2.0 fold

  1. Viscoelastic behaviour of stabilized polyethylenes irradiated with gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Novakovic, Lj; Gal, O; Stannett, V T

    1987-01-01

    Two-cycle creep recovery penetration measurements at 150/sup 0/C are used to determine the viscoelastic parameters for irradiated low density and linear low density polyethylenes, pure and with 0.5% antioxidant. The amplitudes and the time factors of each cycle are calculated using the mechanical model expression. From the differences between the creep parameters of the first and the second cycle, the contribution of the nonelastic component is considered. The efficiency of radiation crosslinking of different systems is discussed on the base of the corresponding compliances.

  2. Study of adhesion and surface properties of low-density poly(ethylene) pre-treated by cold discharge plasma

    Czech Academy of Sciences Publication Activity Database

    Novák, I.; Števiar, M.; Chodák, I.; Krupa, I.; Nedelčev, T.; Špírková, Milena; Chehimi, M. M.; Mosnáček, J.; Kleinová, A.

    2007-01-01

    Roč. 18, č. 2 (2007), s. 97-105 ISSN 1042-7147. [International Conference on Polymeric Materials in Automotive , Slovak Rubber Conference /17./. Bratislava, 10.5.2005-12.5.2005] R&D Projects: GA AV ČR IAA400500505 Grant - others:Slovak Grant Agency VEGA(SK) 2/4024/04; Slovak Grant Agency(SK) 2/6015/06; Slovak Science and Technology Assistance Agency APVT(SK) 51-004-904; Slovak Science and Technology Assistance Agency APVT(SK) 99-035-004 Institutional research plan: CEZ:AV0Z40500505 Keywords : adhesion * atomic force microscopy * plasma Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.504, year: 2007

  3. Re-usable low density polyethylene aRm glove foR pueRpeRal ...

    African Journals Online (AJOL)

    2008-07-07

    Jul 7, 2008 ... E a s t a f r i c a n M E d i c a l J o u r n a l . July 2008. intRoduCtion ... sheet using a razor blade or a scissors. later the top flap of the cut ... absorbed before incubation at 37º c for 24 to 48 hours. the remaining ... and many other properties can be inferred (figure. 2). for this test .... on the long run. the hcW ...

  4. A modelling implementation of climate change on biodegradation of Low-Density Polyethylene (LDPE by Aspergillus niger in soil

    Directory of Open Access Journals (Sweden)

    Farzin Shabani

    2015-07-01

    Main conclusions:  Accurately evaluating the impact of landfilling on land use and predicting future climate are vital components for effective long-term planning of waste management. From a social and economic perspective, utilization of our mapped projections to detect suitable regions for establishing landfills in areas highly sustainable for microorganisms like A. niger growth will allow a significant cost reduction and improve the performance of biodegradation of LDPE over a long period of time, through making use of natural climatic and environmental factors.

  5. Adhesion, Growth, and Maturation of Vascular Smooth Muscle Cells on Low-Density Polyethylene Grafted with Bioactive Substances

    Czech Academy of Sciences Publication Activity Database

    Pařízek, Martin; Kasálková-Slepičková, N.; Bačáková, Lucie; Švindrych, Zdeněk; Slepička, P.; Bačáková, Markéta; Lisá, Věra; Švorčík, V.

    2013-01-01

    Roč. 2013, č. 2013 (2013), s. 371430 ISSN 2314-6133 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:67985823 Keywords : biotechnology * tissue replacements * vascular smooth muscle cells * adhesion * modification Subject RIV: JJ - Other Materials

  6. BIODEGRADABLE PLASTICS FROM A MIXTURE OF LOW DENSITY POLYETHYLENE (LDPE AND CASSAVA STARCH WITH THE ADDITION OF ACRYLIC ACID

    Directory of Open Access Journals (Sweden)

    Susilawati Susilawati

    2013-05-01

    Full Text Available A research of preparation biodegradable plastics, from LDPE and cassava starch mixture with the addition of acrylic acid, had been conducted. This research purpose to  studied compatibility properties of the material and percent weight loss during the biodegradation test. Optimum weight loss (59,26% was showed after 60 days witches LDPE and starch composition ratio 6 : 4 (w/w  while tensile strength  equal to 0,38 Kgf/mm2.  SEM characterization showed that biodegradation has occurred by  formation of hole in the biodegradable plastic surface. DTA test gave Tg = 130 °C, Tm = 230 °C and Td = 370-450 °C while FT-IR analysis showed that the biodegradable plastics have a chemistry interaction.

  7. Low Density Polyethylene (LDPE blends based on Poly(3-Hydroxi-Butyrate (PHB and Guar Gum (GG biodegradable polymers

    Directory of Open Access Journals (Sweden)

    Marisa Cristina Guimarães Rocha

    2015-02-01

    Full Text Available LDPE blends based on PHB and GG biodegradable polymers were prepared by melt mixing in a twin screw extruder. The mechanical properties of the materials were evaluated. Preliminary information about the biodegradation behavior of the specimens was obtained by visual observation of samples removed from the simulated soil in 90 days. The results indicated that LDPE/PHB blends may be used for designing LDPE based materials with increased susceptibility to degradation, if elongation at break and impact properties are not determinant factors of their performance. LDPE based materials on GG present values of flexural and mechanical strength lower than those of LDPE/PHB blends. LDPE/PHB/GG blends exhibit unsatisfactory properties. Apparently, the effect of addition of GG to LDPE on the biodegradation behavior of LDPE/GG blends was less intense than the effect caused by addition of PHB to the blends. Similar observation has occurred with the partial replacement of GG by PHB in the ternary blends.

  8. Compatibilization of low-density polyethylene/polystyrene blends by segmented EB(PS-block-EB)(n) block copolymers

    NARCIS (Netherlands)

    Kroeze, E; ten Brinke, G.; Hadziioannou, G

    Hydrogenated segmented poly[butadiene-block-(styrene-block-butadiene)(n)] block copolymers, which were developed by use of a polymeric iniferter technique, were tested on their compatibilizing effectiveness for (10/90) LDPE/PS blends. They were found to be effective compatibilizers for this mixture,

  9. Nonlinear tensile creep of linear low density polyethylene/fumed silica nanocomposites: time-strain superposition and creep prediction

    Czech Academy of Sciences Publication Activity Database

    Dorigato, A.; Pegoretti, A.; Kolařík, Jan

    2010-01-01

    Roč. 31, č. 11 (2010), s. 1947-1955 ISSN 0272-8397 R&D Projects: GA ČR GA106/09/1348 Institutional research plan: CEZ:AV0Z40500505 Keywords : heterogeneous polymer blends * free-volume theory * copolymer blends Subject RIV: JI - Composite Materials Impact factor: 0.998, year: 2010

  10. Chemical recycling of plastic wastes made from polyethylene (LDPE and HDPE) and polypropylene (PP)

    International Nuclear Information System (INIS)

    Achilias, D.S.; Roupakias, C.; Megalokonomos, P.; Lappas, A.A.; Antonakou, E.V.

    2007-01-01

    The recycling of either model polymers or waste products based on low-density polyethylene (LDPE), high-density polyethylene (HDPE) or polypropylene (PP) is examined using the dissolution/reprecipitation method, as well as pyrolysis. In the first technique, different solvents/non-solvents were examined at different weight percent amounts and temperatures using as raw material both model polymers and commercial products (packaging film, bags, pipes, food-retail outlets). The recovery of polymer in every case was greater than 90%. FT-IR spectra and tensile mechanical properties of the samples before and after recycling were measured. Furthermore, catalytic pyrolysis was carried out in a laboratory fixed bed reactor with an FCC catalyst using again model polymers and waste products as raw materials. Analysis of the derived gases and oils showed that pyrolysis gave a mainly aliphatic composition consisting of a series of hydrocarbons (alkanes and alkenes), with a great potential to be recycled back into the petrochemical industry as a feedstock for the production of new plastics or refined fuels

  11. Chemical recycling of plastic wastes made from polyethylene (LDPE and HDPE) and polypropylene (PP).

    Science.gov (United States)

    Achilias, D S; Roupakias, C; Megalokonomos, P; Lappas, A A; Antonakou, Epsilon V

    2007-11-19

    The recycling of either model polymers or waste products based on low-density polyethylene (LDPE), high-density polyethylene (HDPE) or polypropylene (PP) is examined using the dissolution/reprecipitation method, as well as pyrolysis. In the first technique, different solvents/non-solvents were examined at different weight percent amounts and temperatures using as raw material both model polymers and commercial products (packaging film, bags, pipes, food-retail outlets). The recovery of polymer in every case was greater than 90%. FT-IR spectra and tensile mechanical properties of the samples before and after recycling were measured. Furthermore, catalytic pyrolysis was carried out in a laboratory fixed bed reactor with an FCC catalyst using again model polymers and waste products as raw materials. Analysis of the derived gases and oils showed that pyrolysis gave a mainly aliphatic composition consisting of a series of hydrocarbons (alkanes and alkenes), with a great potential to be recycled back into the petrochemical industry as a feedstock for the production of new plastics or refined fuels.

  12. Low density in liver of idiopathic portal hypertension. A computed tomographic observation with possible diagnostic significance

    Energy Technology Data Exchange (ETDEWEB)

    Ishito, Hiroyuki

    1988-01-01

    In order to evaluate the diagnostic value of low density in liver on computed tomography (CT), CT scans of 11 patients with idiopathic portal hypertension (IPH) were compared with those from 22 cirrhotic patients, two patients with scarred liver and 16 normal subjects. Low densities on plain CT scans in patients with IPH were distinctly different from those observed in normal liver. Some of the low densities had irregular shape with unclear margin and were scattered near the liver surface, and others had vessel-like structures with unclear margin and extended as far as near the liver surface. Ten of the 11 patients with IPH had low densities mentioned above, while none of the 22 cirrhotic patients had such low densities. The present results suggest that the presence of low densities in liver on plain CT scan is clinically beneficial in diagnosis of IPH.

  13. Synthesis of polyaniline catalysed by Cu(I), Ni(II) and Fe(II) supported on the polyethylene-i-acrylic acid copolymer; Sintesis de polianilina catalizada por Cu(I), Ni(II) y Fe(II), soportados en el copolimero polietileno-i-acido acrilico

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, L.; Urena, F.; Lopez, R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    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)

  14. Low-density moderation in the storage of PWR fuel assemblies

    International Nuclear Information System (INIS)

    Alcorn, F.M.

    1987-01-01

    The nuclear criticality safety of PWR fuel storage arrays requires that the potential of low-density moderation within the array be considered. The calculated criticality effect of low-density moderation in a typical PWR fuel assembly array is described in this paper. Calculated reactivity due to low-density moderation can vary significantly between physics codes that have been validated for well moderated systems. The availability of appropriate benchmark experiments for low-density moderation is quite limited; attempts to validate against the one set of suitable experiments at low density have been disappointing. Calculations indicate that a typical array may be unacceptable should the array be subjected to interstitial moderation equivalent to 5 % of full density water. Array parameters (such as spacing and size) will dramatically affect the calculated maximum K-eff at low-density moderation. Administrative and engineered control may be necessary to assure maintenance of safety at low-density moderation. Potential sources for low-density moderation are discussed; in general, accidentally achieving degrees of low-density moderation which might lead to a compromise of safety are not credible. (author)

  15. Cholesterol transfer from normal and atherogenic low density lipoproteins to Mycoplasma membranes

    International Nuclear Information System (INIS)

    Mitschelen, J.J.; St Clair, R.W.; Hester, S.H.

    1981-01-01

    The purpose of this study was to determine whether the free cholesterol of hypercholesterolemic low density lipoprotein from cholesterol-fed nonhuman primates has a greater potential for surface transfer to cell membranes than does the free cholesterol of normal low density lipoprotein. The low density lipoproteins were isolated from normal and hypercholesterolemic rhesus and cynomolgus monkeys, incubated with membranes from Acholeplasma laidlawii, a mycoplasma species devoid of cholesterol in its membranes, and the mass transfer of free cholesterol determined by measuring membrane cholesterol content. Since these membranes neither synthesize nor esterify cholesterol, nor degrade the protein or cholesterol ester moieties of low density lipoprotein, they are an ideal model with which to study differences in the cholesterol transfer potential of low density lipoprotein independent of the uptake of the intact low density lipoprotein particle. These studies indicate that, even though there are marked differences in the cholesterol composition of normal and hypercholesterolemic low density lipoproteins, this does not result in a greater chemical potential for surface transfer of free cholesterol. Consequently, if a difference in the surface transfer of free cholesterol is responsible for the enhanced ability of hypercholesterolemic low density lipoprotein to promote cellular cholesterol accumulation and, perhaps, also atherosclerosis, it must be the result of differences in the interaction to the hypercholesterolemic low density lipoprotein with the more complicated mammalian cell membranes, rather than differences in the chemical potential for cholesterol transfer

  16. Low-density lipoprotein apheresis: an evidence-based analysis.

    Science.gov (United States)

    2007-01-01

    To assess the effectiveness and safety of low-density lipoprotein (LDL) apheresis performed with the heparin-induced extracorporeal LDL precipitation (HELP) system for the treatment of patients with refractory homozygous (HMZ) and heterozygous (HTZ) familial hypercholesterolemia (FH). BACKGROUND ON FAMILIAL HYPERCHOLESTEROLEMIA: Familial hypercholesterolemia is a genetic autosomal dominant disorder that is caused by several mutations in the LDL-receptor gene. The reduced number or absence of functional LDL receptors results in impaired hepatic clearance of circulating low-density lipoprotein cholesterol (LDL-C) particles, which results in extremely high levels of LDL-C in the bloodstream. Familial hypercholesterolemia is characterized by excess LDL-C deposits in tendons and arterial walls, early onset of atherosclerotic disease, and premature cardiac death. Familial hypercholesterolemia occurs in both HTZ and HMZ forms. Heterozygous FH is one of the most common monogenic metabolic disorders in the general population, occurring in approximately 1 in 500 individuals. Nevertheless, HTZ FH is largely undiagnosed and an accurate diagnosis occurs in only about 15% of affected patients in Canada. Thus, it is estimated that there are approximately 3,800 diagnosed and 21,680 undiagnosed cases of HTZ FH in Ontario. In HTZ FH patients, half of the LDL receptors do not work properly or are absent, resulting in plasma LDL-C levels 2- to 3-fold higher than normal (range 7-15mmol/L or 300-500mg/dL). Most HTZ FH patients are not diagnosed until middle age when either they or one of their siblings present with symptomatic coronary artery disease (CAD). Without lipid-lowering treatment, 50% of males die before the age of 50 and 25% of females die before the age of 60, from myocardial infarction or sudden death. In contrast to the HTZ form, HMZ FH is rare (occurring in 1 case per million persons) and more severe, with a 6- to 8-fold elevation in plasma LDL-C levels (range 15-25mmol

  17. Effect of PVDC on the Fire Performance of Ultra-Low Density Fiberboards (ULDFs

    Directory of Open Access Journals (Sweden)

    Zhenzeng Wu

    2016-08-01

    Full Text Available Poly vinylidene chloride-vinyl chloride emulsions (PVDC were added as a substitute for chlorinated paraffin (CP in the preparation of ultra-low density fiberboards (ULDFs. The micromorphology and fire performance of ULDFs were investigated using a scanning electron microscope, limiting oxygen index instrument, and cone calorimeter. The results showed that PVDC specimens were coated with a regularly smooth film, while the distribution of CP inside CP specimens was uneven. The limiting oxygen index increased with the dosage of PVDC, then reached a plateau at 50 mL and 28%, slightly higher than CP specimens (27.3%. The peak of heat release rate, mean heat release rate, mean CO, and total smoke release of PVDC specimens was reduced 43.3%, 13.5%, 38.5%, and 51.5% lower than respective CP specimens, and with nearly the same total heat release (only 0.04 MJ/m2 higher. Thus, PVDC exhibited excellent heat-reducing and smoke-suppressing properties and could replace CP in ULDFs.

  18. Catalytic thermal decomposition of polyethylene determined by thermogravimetric treatment

    International Nuclear Information System (INIS)

    Nisar, J.; Khan, M.S.; Khan, M.A.

    2014-01-01

    In this study low density polyethylene (LDPE) has been studied by thermogravimetric analysis (TGA) using commercially available oxides as catalysts. TGA experiments were used to evaluate the activity of different catalysts on low density polyethylene (LDPE) degradation and to study the effect in terms of type and amount of catalyst used. All the catalysts used improved the pyrolysis of LDPE. The reaction rates were found to increase with increase in amount of catalyst. Among the catalysts used, alumina acidic active catalyst performed better at all four fractions. Moreover, alumina acidic active reduced weight loss temperature better than others tested catalysts. The effect of alumina neutral catalyst on the pyrolysis of LDPE is less pronounced due to its small surface area and pore size. The effect of these catalysts showed that surface area, number of acidic sites and pore size were found as the key factors for the energy efficient degradation of polymers. (author)

  19. Study on Optoelectronic Characteristics of Sn-Doped ZnO Thin Films on Poly(ethylene terephthalate) and Indium Tin Oxide/Poly(ethylene terephthalate) Flexible Substrates

    Science.gov (United States)

    Cheng, Chi-Hwa; Chen, Mi; Chiou, Chin-Lung; Liu, Xing-Yang; Weng, Lin-Song; Koo, Horng-Show

    2013-05-01

    Transparent conductive oxides of Sn-doped ZnO (SZO) films with doping weight ratios of 2.0, 3.0, 4.0, and 5.0 wt % have been deposited on indium tin oxide (ITO)/poly(ethylene terephthalate) (PET) and PET flexible substrates at room temperature by pulsed laser deposition (PLD). Resultant films of SZO on ITO/PET and PET flexible substrates are amorphous in phase. It is found that undoped and SZO films on ITO/PET is anomalously better than films on PET in optical transmittance in the range of longer wavelength, possibly due to the refraction index difference between SZO, ITO films, and PET substrates, Burstein-Moss effect and optical interference of SZO/ITO bilayer films and substrate materials, and furthermore resulting in the decrement of reflection. The lowest electrical resistivity (ρ) of 4.0 wt % SZO films on flexible substrates of PET and ITO/PET are 3.8×10-2 and ρ= 1.2×10-2 Ω.cm, respectively. It is found that electrical and optical properties of the resultant films are greatly dependent on various amount of Sn element doping effect and substrate material characteristics.

  20. Do Low-Density Diets Improve Broiler Breeder Welfare During Rearing and Laying.

    NARCIS (Netherlands)

    Jong, de I.C.; Enting, H.; Voorst, van A.; Blokhuis, H.J.

    2005-01-01

    Low-density diets may improve welfare of restricted fed broiler breeders by increasing feed intake time with less frustration of feed intake behavior as a result. Moreover, low-density diets may promote satiety through a more filled gastrointestinal tract, and thus feelings of hunger may be reduced.

  1. Scat-detection dogs survey low density moose in New York

    Science.gov (United States)

    Heidi Kretser; Michale Glennon; Alice Whitelaw; Aimee Hurt; Kristine Pilgrim; Michael Schwartz

    2016-01-01

    The difficulty of collecting occurrence and population dynamics data in mammalian populations of low density poses challenges for making informed management decisions. We assessed the use of scat-detection dogs to search for fecal pellets in a low density moose (Alces alces) population in the Adirondack Park in New York State, and the success rate of DNA...

  2. Mechanical and thermal properties of physically-blended-plastic films

    International Nuclear Information System (INIS)

    Abu Issa, M. S.

    1983-10-01

    Low density polyethylene (LDPE) and isotactic polypropylene (PP) blend were produced in film form and were characterized by a number of techniques such as wide-angle x-ray diffraction (WAXD), differential thermal analysis (DTA), scanning electron microscopy (SEM), and instron tensile testing. Results of WAXD and DTA showed conclusively that the two components in the blend are incompatible. SEM micrographs indicated that the 60/40 and 40/60 PP/PE blends show approximately fine homogeneous dispersion of the minor component into the matrix of the major component. The mechanical properties of the blend films improved with respect to the PE homo polymer. The improvement was more remarkable with the increase of the PP component in the blend. Results obtained in this work were explained in terms of crystallinity and the crystallite orientation. 28 refs., 29 figs., 5 tabs. (A.M.H.)

  3. Quantification of branching in model three-arm star polyethylene

    KAUST Repository

    Ramachandran, Ramnath; Beaucage, Gregory B.; Rai, Durgesh K.; Lohse, David J.; Sun, Thomas; Tsou, Andy; Norman, Alexander Iain; Hadjichristidis, Nikolaos

    2012-01-01

    The versatility of a novel scaling approach in quantifying the structure of model well-defined 3-arm star polyethylene molecules is presented. Many commercial polyethylenes have long side branches, and the nature and quantity of these branches varies widely among the various forms. For instance, low-density polyethylene (LDPE) is typically a highly branched structure with broad distributions in branch content, branch lengths and branch generation (in hyperbranched structures). This makes it difficult to accurately quantify the structure and the inherent structure-property relationships. To overcome this drawback, model well-defined hydrogenated polybutadiene (HPB) structures have been synthesized via anionic polymerization and hydrogenation to serve as model analogues to long-chain branched polyethylene. In this article, model 3-arm star polyethylene molecules are quantified using the scaling approach. Along with the long-chain branch content in polyethylene, the approach also provides unique measurements of long-chain branch length and hyperbranch content. Such detailed description facilitates better understanding of the effect of branching on the physical properties of polyethylene. © 2012 American Chemical Society.

  4. Quantification of branching in model three-arm star polyethylene

    KAUST Repository

    Ramachandran, Ramnath

    2012-01-24

    The versatility of a novel scaling approach in quantifying the structure of model well-defined 3-arm star polyethylene molecules is presented. Many commercial polyethylenes have long side branches, and the nature and quantity of these branches varies widely among the various forms. For instance, low-density polyethylene (LDPE) is typically a highly branched structure with broad distributions in branch content, branch lengths and branch generation (in hyperbranched structures). This makes it difficult to accurately quantify the structure and the inherent structure-property relationships. To overcome this drawback, model well-defined hydrogenated polybutadiene (HPB) structures have been synthesized via anionic polymerization and hydrogenation to serve as model analogues to long-chain branched polyethylene. In this article, model 3-arm star polyethylene molecules are quantified using the scaling approach. Along with the long-chain branch content in polyethylene, the approach also provides unique measurements of long-chain branch length and hyperbranch content. Such detailed description facilitates better understanding of the effect of branching on the physical properties of polyethylene. © 2012 American Chemical Society.

  5. Radiation Induced Crosslinking of Polyethylene in the Presence of Bifunctional Vinyl Monomers

    DEFF Research Database (Denmark)

    Joshi, M. S.; Singer, Klaus Albert Julius; Silverman, J.

    1977-01-01

    Several reports have been published showing that the radiation induced grafting of bifunctional vinyl monomers to low density polyethylene results in a product with an unusually high density of crosslinks. The same grafting reactions are shown to reduce the incipient gel dose by more than a factor...... of fifty. This paper is concerned with the apparent crosslinking produced by the radiation grafting of two monomers to polyethylene: acrylic acid and acrylonitrile....

  6. Maximizing performance in supercritical fluid chromatography using low-density mobile phases.

    Science.gov (United States)

    Gritti, Fabrice; Fogwill, Michael; Gilar, Martin; Jarrell, Joseph A

    2016-10-14

    The performance of a 3.0mm×150mm column packed with 1.8μm fully porous HSS-SB-C 18 particles was investigated in supercritical fluid chromatography (SFC) with low-density, highly expansible carbon dioxide. These conditions are selected for the analysis of semi-volatile compounds. Elevated temperatures (>100°C) were then combined with low column back pressures (<100bar). In this work, the inlet temperature of pure carbon dioxide was set at 107°C, the active back pressure regulator (ABPR) pressure was fixed at 100bar, and the flow rate was set at 2.1mL/min at 12°C (liquefied carbon dioxide) and at an inlet column pressure close to 300bar. Nine n-alkylbenzenes (from benzene to octadecylbenzene) were injected under linear (no sample overload) conditions. The severe steepness of the temperature gradients across the column diameter were predicted from a simplified heat transfer model. Such conditions dramatically lower the column performance by affecting the symmetry of the peak shape. In order to cope with this problem, three different approaches were experimentally tested. They include (1) the decoupling and the proper selection of the inlet eluent temperature with respect to the oven temperature, (2) the partial thermal insulation of the column using polyethylene aerogel, and (3) the application of a high vacuum (10 -5 Torr provided by a turbo-molecular pump) in a housing chamber surrounding the whole column body. The results reveal that (1) the column efficiency can be maximized by properly selecting the difference between the eluent and the oven temperatures, (2) the mere wrapping of the column with an excellent insulating material is insufficient to fully eliminate heat exchanges by conduction and the undesirable radial density gradients across the column i.d., and (3) the complete thermal insulation of the SFC column under high vacuum allows to maximize the column efficiency by maintaining the integrity of the peak shape. Copyright © 2016 Elsevier B.V. All

  7. Surface modification of polyethylene by plasma; Modificacion superficial de polietileno por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Colin O, E

    2003-07-01

    The products made of polyethylene (PE) go from construction materials, electric insulating until packing material. The films for bags and pack occupy 83.6% of the distribution of the market of PE approximately. The enormous quantity of PE that is generated by its indiscriminate use brings as consequence a deterioration to the atmosphere, due to the long life that they present as waste. This work is a study on the modification of low density polyethylene films. In this type of thin materials, the changes in the surface meet with largely on the conformation of the rest of the material. To induce changes that modify the surface of PE, plasmas were used with reactive atmospheres of air, oxygen and nitrogen. The experimentation that was carries out went to introduce the PE to a cylindrical reactor where it was generated the plasma of air, oxygen and nitrogen to different times of exposure. After having carried out the exposure to the plasma, it was found that in the polyethylene it modifies their morphology, crystallinity, hydrophobicity, composition and electric conductivity. The analytical techniques that were used to characterize later to the polyethylene of being in contact with the plasma were: X-ray diffraction, Scanning Electron Microscopy, Infrared spectroscopy, Electric conductivity, Angle of contact and finally Thermal Gravimetric Analysis. The content of this work it is presented in five chapters: In the chapter 1 there are presented some general concepts of plasma and of the one polymer in study PE. In the chapter 2 it is made a general revision on modification of surfaces, as well as the properties that were modified in polymeric materials that were exposed to plasma in previous works. In the chapter 3 the experimental part and the conditions used are described in the modification of the PE. Also in this chapter a brief description it is made of the used characterization techniques. The results and discussion are presented in the chapter 4. These results

  8. Regions of low density in the contrast-enhanced pituitary gland: normal and pathologic processes

    International Nuclear Information System (INIS)

    Chambers, E.F.; Turski, P.A.; LaMasters, D.; Newton, T.H.

    1982-01-01

    The incidence of low-density regions in the contrast-enhanced pituitary gland and the possible causes of these regions were investigated by a retrospective review of computed tomographic (CT) scans of the head in 50 patients and autopsy specimens of the pituitary in 100 other patients. It was found that focal areas of low density within the contrast enhanced pituitary gland can be caused by various normal and pathologic conditions such as pituitary microadenomas, pars intermedia cysts, foci of metastasis, infarcts, epidermoid cysts, and abscesses. Although most focal low-density regions probably represent pituitary microadenomas, careful clinical correlation is needed to establish a diagnosis

  9. Antimicrobial Activity of TiO2 Nanoparticle-Coated Film for Potential Food Packaging Applications

    Directory of Open Access Journals (Sweden)

    Siti Hajar Othman

    2014-01-01

    Full Text Available Recent uses of titanium dioxide (TiO2 have involved various applications which include the food industry. This study aims to develop TiO2 nanoparticle-coated film for potential food packaging applications due to the photocatalytic antimicrobial property of TiO2. The TiO2 nanoparticles with varying concentrations (0–0.11 g/ 100 mL organic solvent were coated on food packaging film, particularly low density polyethylene (LDPE film. The antimicrobial activity of the films was investigated by their capability to inactivate Escherichia coli (E. coli in an actual food packaging application test under various conditions, including types of light (fluorescent and ultraviolet (UV and the length of time the film was exposed to light (one–three days. The antimicrobial activity of the TiO2 nanoparticle-coated films exposed under both types of lighting was found to increase with an increase in the TiO2 nanoparticle concentration and the light exposure time. It was also found that the antimicrobial activity of the films exposed under UV light was higher than that under fluorescent light. The developed film has the potential to be used as a food packaging film that can extend the shelf life, maintain the quality, and assure the safety of food.

  10. Polyethylene solidification of low-level wastes

    International Nuclear Information System (INIS)

    Kalb, P.D.; Colombo, P.

    1985-02-01

    This topical report describes the results of an investigation on the solidification of low-level radioactive waste in polyethylene. Waste streams selected for this study included those which result from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Four types of commercially available low-density polyethylenes were employed which encompass a range of processing and property characteristics. Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste and polyethylene type. Property evaluation testing was performed on laboratory-scale specimens to assess the potential behavior of actual waste forms in a disposal environment. Waste form property tests included water immersion, deformation under compressive load, thermal cycling and radionuclide leaching. Recommended waste loadings of 70 wt % sodium sulfate, 50 wt % boric acid, 40 wt % incinerator ash, and 30 wt % ion exchange resins, which are based on process control and waste form performance considerations are reported. 37 refs., 33 figs., 22 tabs

  11. Fluorocarbon seal replaces metal piston ring in low density gas environment

    Science.gov (United States)

    Morath, W. D.; Morgan, N. E.

    1967-01-01

    Reinforced fluorocarbon cupseal, which provides an integral lip-type seal, replaces the metal piston rings in piston-cylinder configurations used in the compression of low density gases. The fluorocarbon seal may be used as cryogenic compressor piston seals.

  12. Development of Low Density CaMg-A1-Based Bulk Metallic Glasses (Preprint)

    National Research Council Canada - National Science Library

    Senkov, O. N; Scott, J. M; Miracle, D. B

    2006-01-01

    Low density Ca-Mg-Al-based bulk metallic glasses containing additionally Cu and Zn, were produced by a copper mold casting method as wedge-shaped samples with thicknesses varying from 0.5 mm to 10 rom...

  13. Response of ecosystem metabolism to low densities of spawning Chinook Salmon

    Science.gov (United States)

    Joseph R. Benjamin; J. Ryan Bellmore; Grace A. Watson

    2016-01-01

    Marine derived nutrients delivered by large runs of returning salmon are thought to subsidize the in situ food resources that support juvenile salmon. In the Pacific Northwest, USA, salmon have declined to salmon runs. We explored whether low densities...

  14. Elaboration of recycled polyethylene foams reticulated by radiation

    International Nuclear Information System (INIS)

    Galicia M, M.

    2000-01-01

    In this work some obtained results are presented to make irradiation tests on recycled polymeric material (polyethylene) as well as mixtures of this with certain additive classes (foaming and reticulating agents) which will be used for the foams elaboration, objective of this work. Two types of foaming basically exist which are elaborated with low density polyethylene base. They are: a) the extruded and, b) the reticulated through ionizing radiation and chemically. Some of the properties that the expanded or foamed polyethylene are: flexibility, resistance, thermal stability, inter medium mechanical properties between the highly flexible foams and rigid among others. All of them determined by the cell type which conform them. Also was carried out the characterization of the obtained material contributing of this manner to diminish the quantity of solid wastes generated. (Author)

  15. Preparation and Characterization of Antimicrobial Films Based on LDPE/Ag Nanoparticles with Potential Uses in Food and Health Industries

    Science.gov (United States)

    Pontes-Quero, Gloria María; Corral, Angélica

    2018-01-01

    In this work, the antimicrobial effect of silver nanoparticles in polyethylene based nanocomposites has been investigated using a non-conventional processing method to produce homogeneous materials. High energy ball milling under cryogenic conditions was used to achieve a powder of well-blended low-density polyethylene and commercial silver nanoparticles. The final composites in the form of films were obtained by hot pressing. The effect of various silver nanoparticles content (0, 0.5, 1 and 2 wt %) on the properties of low-density polyethylene and the antimicrobial effectiveness of the composite against DH5α Escherichia coli were studied. The presence of silver nanoparticles did not seem to affect the surface energy and thermal properties of the materials. Apart from the inhibition of bacterial growth, slight changes in the aspect ratio of the bacteria with the content of particles were observed, suggesting a direct relationship between the presence of silver nanoparticles and the proliferation of DH5α E. coli (Escherichia coli) cells. Results indicate that these materials may be used to commercially produce antimicrobial polymers with potential applications in the food and health industries. PMID:29364193

  16. Obtention of scintillography images by low density lipoproteins labelled with technetium 99

    International Nuclear Information System (INIS)

    Silva, S.; Coelho, I.; Zanardo, E.; Pileggi, F.; Meneguethi, C.; Maranhao, R.C.

    1992-01-01

    The low density lipoproteins carry the most part of the cholesterol in the blood plasma. These lipoproteins are labelled with technetium-99-m and have been used for obtaining images in nuclear medicine. The introduction of this technique is presented, aiming futures clinical uses. Scintillographic images are obtained 25 minutes and 24 hours after the injection of 3 m Ci of low density lipoproteins - technetium-99 m in rabbits. (C.G.C.)

  17. A review of low density porous materials used in laser plasma experiments

    Science.gov (United States)

    Nagai, Keiji; Musgrave, Christopher S. A.; Nazarov, Wigen

    2018-03-01

    This review describes and categorizes the synthesis and properties of low density porous materials, which are commonly referred to as foams and are utilized for laser plasma experiments. By focusing a high-power laser on a small target composed of these materials, high energy and density states can be produced. In the past decade or so, various new target fabrication techniques have been developed by many laboratories that use high energy lasers and consequently, many publications and reviews followed these developments. However, the emphasis so far has been on targets that did not utilize low density porous materials. This review therefore, attempts to redress this balance and endeavors to review low density materials used in laser plasma experiments in recent years. The emphasis of this review will be on aspects of low density materials that are of relevance to high energy laser plasma experiments. Aspects of low density materials such as densities, elemental compositions, macroscopic structures, nanostructures, and characterization of these materials will be covered. Also, there will be a brief mention of how these aspects affect the results in laser plasma experiments and the constrictions that these requirements put on the fabrication of low density materials relevant to this field. This review is written from the chemists' point of view to aid physicists and the new comers to this field.

  18. IMPROVING GLOBALlAND30 ARTIFICIAL TYPE EXTRACTION ACCURACY IN LOW-DENSITY RESIDENTS

    Directory of Open Access Journals (Sweden)

    L. Hou

    2016-06-01

    Full Text Available GlobalLand 30 is the first 30m resolution land cover product in the world. It covers the area within 80°N and 80°S. There are ten classes including artificial cover, water bodies, woodland, lawn, bare land, cultivated land, wetland, sea area, shrub and snow,. The TM imagery from Landsat is the main data source of GlobalLand 30. In the artificial surface type, one of the omission error happened on low-density residents’ part. In TM images, hash distribution is one of the typical characteristics of the low-density residents, and another one is there are a lot of cultivated lands surrounded the low-density residents. Thus made the low-density residents part being blurred with cultivated land. In order to solve this problem, nighttime light remote sensing image is used as a referenced data, and on the basis of NDBI, we add TM6 to calculate the amount of surface thermal radiation index TR-NDBI (Thermal Radiation Normalized Difference Building Index to achieve the purpose of extracting low-density residents. The result shows that using TR-NDBI and the nighttime light remote sensing image are a feasible and effective method for extracting low-density residents’ areas.

  19. Enhanced antioxidant activity of polyolefin films integrated with grape tannins.

    Science.gov (United States)

    Olejar, Kenneth J; Ray, Sudip; Kilmartin, Paul A

    2016-06-01

    A natural antioxidant derived from an agro-waste of the wine industry, grape tannin, was incorporated by melt blending into three different polyolefins (high-density polyethylene, linear low-density polyethylene and polypropylene) to introduce antioxidant functionality. Significant antioxidant activity was observed at 1% tannin inclusion in all polymer blends. The antioxidant activity was observed to increase steadily with a greater concentration of grape tannins, the highest increases being seen with polypropylene. The mechanical and thermal properties of the polymer films following antioxidant incorporation were minimally altered with up to 3% grape tannins. All of the polyolefin-grape tannin films successfully passed the leachability test following USP661 standard protocol. Superior antioxidant activity was established in polyolefin thin films by utilization of a bulk grape extract obtained from winery waste. Significant increases in antioxidant activity were seen with 1% extract inclusion. This not only demonstrates the potential for food packaging applications of the polyolefin blends, but also valorizes the agro-waste. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  20. Effect of low-density lateral interfaces on soft-tissue doses

    International Nuclear Information System (INIS)

    Hunt, Margie A.; Desobry, Gregory E.; Fowble, Barbara; Coia, Lawrence R.

    1997-01-01

    phantom. For a given cork width, the interface doses were not significantly dependent on field width but decreased by an additional 2-3% as the length decreased to 4 cm. Additional decreases were also observed when the measurement depth decreased to 3 cm. With a 1-cm width of cork in the field, a lateral distance of 3-4 mm from the interface was necessary to ensure doses of at least 98% of the homogenous dose with 6-MV X-rays. A lateral distance of 6-7 mm was necessary for 10- and 18-MV X rays. Conclusion: Underdosing will occur in the soft tissues adjacent to low-density inhomogeneities. The magnitude depends primarily on the width of the inhomogeneity seen in the treatment field, but also on field size, depth, and beam energy. For treatment fields with a lateral lung interface, a segment of tissue approximately 3-4 mm thick for 6 MV and 6-7 mm thick for higher-energy beams may be underdosed. Lung widths of ≥1.75 cm as observed on film will generally guarantee doses of at least 96% of those calculated with no inhomogeneity corrections. High-energy beams are often used to treat sites in the thorax or breast to improve dose homogeneity throughout the treatment volume. Potential underdosing due to the presence of lung should be considered and may require a decrease in beam energy or an increase in the margin between the target volume and the field edge to ensure adequate treatment

  1. Composite SiO.sub.x./sub./hydrocarbon plasma polymer films prepared by RF magnetron sputtering of SiO.sub.2./sub. and polyethylene or polypropylene

    Czech Academy of Sciences Publication Activity Database

    Pihosh, Y.; Biederman, H.; Slavínská, D.; Kousal, J.; Choukourov, A.; Trchová, Miroslava; Macková, Anna; Boldyryeva, Hanna

    2006-01-01

    Roč. 81, 1-4 (2006), s. 32-37 ISSN 0042-207X R&D Projects: GA MŠk 1P05ME754 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z10480505 Keywords : composite films * magnetron * sputtering Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.834, year: 2006

  2. Raman structural study of melt-mixed blends of isotactic polypropylene with polyethylene of various densities

    Science.gov (United States)

    Prokhorov, K. A.; Nikolaeva, G. Yu; Sagitova, E. A.; Pashinin, P. P.; Guseva, M. A.; Shklyaruk, B. F.; Gerasin, V. A.

    2018-04-01

    We report a Raman structural study of melt-mixed blends of isotactic polypropylene with two grades of polyethylene: linear high-density and branched low-density polyethylenes. Raman methods, which had been suggested for the analysis of neat polyethylene and isotactic polypropylene, were modified in this study for quantitative analysis of polyethylene/polypropylene blends. We revealed the dependence of the degree of crystallinity and conformational composition of macromolecules in the blends on relative content of the blend components and preparation conditions (quenching or annealing). We suggested a simple Raman method for evaluation of the relative content of the components in polyethylene/polypropylene blends. The degree of crystallinity of our samples, evaluated by Raman spectroscopy, is in good agreement with the results of analysis by differential scanning calorimetry.

  3. Variation of physical properties of LDPE greenhouse films due to agrochemicals used during cultivation

    Directory of Open Access Journals (Sweden)

    Evelia Schettini

    2013-09-01

    Full Text Available During protected cultivation, the use of agrochemicals influence the degradation of the greenhouse plastic films. A research was carried out to evaluate how agrochemicals contamination and solar radiation influence the physical properties of low density polyethylene (LDPE films. The LDPE films were manufactured on purpose adding different anti-UV stabilizer systems and were exposed to natural outdoor weathering at the experimental farm of the University of Bari (Italy; 41° 05’ N. Each film was tested as covering of two low tunnels: one was sprayed from inside with commercial agrochemicals containing iron, chlorine and sulphur while the other one was not sprayed and used as control. Radiometric tests were carried out on the new films and on film samples taken at the end of the trial. Analyses on absorption of the selected contaminants were carried out in laboratory on the samples taken at the end of the exposure in the field in order to compare the relative effectiveness of the stabilizing systems under evaluation. The experimental tests showed that the natural weathering together with the agrochemicals did not modify significantly the radiometric properties of the films in the solar and PAR wavelength range. Significant variations were recorded for the stabilised films in the LWIR wavelength range.

  4. Transport, mechanical and global migration data of multilayer copolyamide nanocomposite films with different layouts.

    Science.gov (United States)

    Scarfato, P; Garofalo, E; Di Maio, L; Incarnato, L

    2017-06-01

    Transport, mechanical and global migration data concern multilayer food packaging films with different layouts, all incorporating a layered silicate/polyamide nanocomposite as oxygen barrier layer, and a low-density polyethylene (LDPE) as moisture resistant layer in direct contact with food. The data are related to "Tuning of co-extrusion processing conditions and film layout to optimize the performances of PA/PE multilayer nanocomposite films for food packaging" by Garofalo et al. (2017) [1]. Nanocomposite multilayer films, with different relative layer thicknesses and clay types, were produced using a laboratory scale co-extrusion blown-film equipment and were analyzed in terms of transport to oxygen and water vapor, mechanical properties and overall migration. The results have shown that all the multilayer hybrid films, based on the copolyamide layer filled with Cloisite 30B, displayed the most significant oxygen barrier improvements and the best mechanical properties compared to the unfilled films. No significant alteration of the overall migration values was observed, as expectable [2], [3], [4]. The performance improvement was more relevant in the case of the film with the thinner nanocomposite layer.

  5. Silver-Nanoparticle-Based Screen-Printing and Film Characterization of a Disposable, Dual-Band, Bandstop Filter on a Flexible Polyethylene Terephthalate Substrate

    Directory of Open Access Journals (Sweden)

    Kishor Kumar Adhikari

    2015-01-01

    Full Text Available This paper presents a silver-nanoparticle-based, screen-printed, high-performance, dual-band, bandstop filter (DBBSF on a flexible polyethylene terephthalate (PET substrate. Using screen-printing techniques to process a highly viscous silver printing ink, high-conductivity printed lines were implemented at a web transfer speed of 5 m/min. Characterized by X-ray diffraction (XRD, optical microscopy, atomic force microscopy (AFM, and scanning electron microscopy (SEM, the printed lines were shown to be characterized by smooth surfaces with a root mean square roughness of 7.986 nm; a significantly higher thickness (12.2 μm than the skin depth; and a high conductivity of 2×107 S/m. These excellent printed line characteristics enabled the implementation of a high-selectivity DBBSF using shunt-connected uniform impedance resonators (UIRs. Additionally, the inductive loading effect of T-shaped stubs on the UIRs, which were analyzed using S-parameters based on lumped parameter calculations, was used to improve the return losses of the geometrically optimized DBBSF. The measured minimum return loss and maximum insertion loss of 28.26 and 1.58 dB, respectively, at the central frequencies of 2.56 and 5.29 GHz of a protocol screen-printed DBBSF demonstrated the excellent performance of the material and its significant potential for use in future cost-effective, flexible WiMax and WLAN applications.

  6. Low density lesion in solid mass on CT: Pathologic change and housfield number

    International Nuclear Information System (INIS)

    Han, Tae Il; Lim, Joo Won; Ryu, Kyung Nam; Ko, Young Tae; Song, Mi Jin; Lee, Dong Ho; Lee, Ju Hie

    1994-01-01

    We retrospectively reviewed the pathologic changes and housfield unit of the low density lesion in solid mass on CT. Pathologically proved solid mass was evaluated in regard to the shape and margin of the low density in the mass on the CT scans of 23 patient. The CT number of the low density lesion was correlated with the pathologic changes. Pathologic changes of the low density lesions were; necrosis (n=17), hemorrhage (n=13), cyst (n=4), myxoid degeneration (n=2), hyaline degeneration (n=1), fibrosis (n=1), and mixed cellularity (n=1). In 14 cases, more than 2 pathologic changes were seen. In 11 cases, necrosis was associated with hemorrhage. The CT number ranged from 11.5 to 44.9 Housfield unit(HU) (mean, 25.2 HU). The average CT number was 26.9 HU in hemorrhage and necrosis, 17.2 HU in cystic change, 20.9 HU in myxoid degeneration, 35.7 HU in hyaline de generation, 22.3 HU in fibrosis, and 21.4 HU in mixed cellularity. The hemorrhage and necrosis in 17 cases showed irregular margin, amorphous shape, and showed centrifugal distribution. The cystic change in 4 cases showed well defined margin, round shape, and peripheral location in solid mass. The low density lesions in solid mass on CT represented variable pathologic changes; necrosis, hemorrhage, cyst, myxoid degeneration, hyaline degeneration, fibrosis, and mixed cellularity. Pathologic changes would not be differentiated on the basis of CT number

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  8. Application of Nanofibrillated Cellulose on BOPP/LDPE Film as Oxygen Barrier and Antimicrobial Coating Based on Cold Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Peng Lu

    2018-05-01

    Full Text Available The application of nanofibrillated cellulose (NC films in packaging industry has been hindered by its lack of heat-sealing ability. Incorporation of NC films with the biaxially oriented polypropylene/low density polyethylene (BOPP/LDPE laminates can take advantage of each material and endow the films with novel functions for food packaging applications. In this study, a coating that consists of NC and nisin was applied onto a cold plasma treated BOPP/LDPE film to fabricate a novel active packaging with an improved oxygen barrier performance and an added antimicrobial effect. The results showed that cold plasma treatment improved the surface hydrophilicity of BOPP/LDPE films for better attachment of the coatings. NC coatings significantly enhanced oxygen barrier property of the BOPP/LDPE film, with an oxygen transmission rate as low as 24.02 cc/m2·day as compared to that of the non-coated one (67.03 cc/m2·day. The addition of nisin in the coating at a concentration of 5 mg/g caused no significant change in barrier properties but imparted the film excellent antimicrobial properties, with a growth inhibition of L. monocytogenes by 94%. All films exhibit satisfying mechanical properties and transparency, and this new film has the potential to be used as antimicrobial and oxygen barrier packaging.

  9. Giant surfactants of poly(ethylene oxide)- b-polystyrene-(molecular nanoparticle): nanoparticle-driven self-assembly with sub-10-nm nanostructures in thin films

    Science.gov (United States)

    Hsu, Chih-Hao; Lin, Zhiwei; Dong, Xue-Hui; Hsieh, I.-Fan; Cheng, Stephen Z. D.

    2014-03-01

    Giant surfactants are built upon precisely attaching shape- and volume-persistent molecular nanoparticles (MNP) to polymeric flexible tails. The unique class of self-assembling materials, giant surfactants, has been demonstrated to form self-assembled ordered nanostructures, and their self-assembly behaviors are remarkably sensitive to primary chemical structures. In this work, two sets of giant surfactants with functionalized MNP attached to diblock copolymer tails were studied in thin films. Carboxylic acid-functionalized [60]fullerene (AC60) tethered with PEO- b-PS (PEO-PS-AC60) represents an ABA' (hydrophilic-hydrophobic-hydrophilic) giant surfactant, and fluoro-functionalized polyhedral oligomeric silsesquioxane (FPOSS) tethered with PEO- b-PS (PEO-PS-FPOSS) represents an ABC (hydrophilic-hydrophobic-omniphobic) one. The dissimilar chemical natures of the MNPs result in different arrangement of MNPs in self-assembled structures, the dispersion of AC60 in PEO domain and the single domain of FPOSS. Moreover, the chemically bonded MNPs could induce the originally disordered small molecular PEO- b-PS to form ordered cylindrical and lamellar structure, as evidenced by TEM and GISAXS, leading to sub-10-nm nanostructures of copolymer in the thin film state.

  10. Three cases of acute encephalopathy with low density areas in the occipital lobes on CT

    International Nuclear Information System (INIS)

    Nakajima, Masako; Nakano, Chizuko; Takakura, Hiroki; Otani, Kyoichi.

    1985-01-01

    Three female infants with acute encephalopathy (aged from 5 months to 1 year and 8 months) are presented in whom peculiar features were obtained on cranial CT. Disturbances of consciousness and spasm were seen in all patients. Although two patients had been in good health until the onset, the other patient had had nodular sclerosis. Laboratory data showed no evidence of inflammation in the spinal fluid, but increased levels of transaminase and LDH. CT around 7 days after the onset revealed diffuse low density areas. This was noted in the temporal and occipital lobes, mainly resulting from edema. Follow-up CT examinations revealed localized low density areas corresponding to the surface area, being probably attributable to disturbances of the arterial and venous circulations. In two patients with severe disturbances of consciousness, low density areas became more marked with time. (Namekawa, K.)

  11. Analysis of compaction shock interactions during DDT of low density HMX

    Science.gov (United States)

    Rao, Pratap T.; Gonthier, Keith A.

    2017-01-01

    Deflagration-to-Detonation Transition (DDT) in confined, low density granular HMX occurs by a complex mechanism that involves compaction shock interactions within the material. Piston driven DDT experiments indicate that detonation is abruptly triggered by the interaction of a strong combustion-supported secondary shock and a piston-supported primary (input) shock, where the nature of the interaction depends on initial packing density and primary shock strength. These interactions influence transition by affecting dissipative heating within the microstructure during pore collapse. Inert meso-scale simulations of successive shock loading of low density HMX are performed to examine how dissipation and hot-spot formation are affected by the initial density, and the primary and secondary shock strengths. This information is used to formulate an ignition and burn model for low density HMX that accounts for the effect of shock densensitization on burn. Preliminary DDT predictions are presented that illustrate how primary shock strength affects the transition mechanism.

  12. Experimental hypothyroidism modulates the expression of the low density lipoprotein receptor by the liver

    International Nuclear Information System (INIS)

    Scarabottolo, Lia; Trezzi, Ermanno; Roma, Paola; Catapano, A.L.

    1986-01-01

    The effect of exprimental hypothyroidism of the catabolism of plasma lipoproteins and on the expression of low density lipoprotein receptors by the liver was investigated in rats made hypothyroid by surgery. The animals developed mild hypercholesterolemia, mainly due to an increase of plasma low density lipoprotein, while other lipoprotein classes were only marginally affected. Kinetic studies using ( 125 I)LDL indicated that a decreased fractional catabolic rate of the lipoprotein was responsible for this finding in agreement with the in vitro observation of a reduced binding of lipoproteins to liver membranes from hyperthyroid rats and with the demonstrations, by ligand blotting analysis, of a decreasd expression of lipoprotein receptors in liver membranes. These data suggest that hypothyroidism affects lipoprotein distribution also by decreasing the catabolism of low density lipoproteins by the liver (author)

  13. Polyethylene Glycol 3350

    Science.gov (United States)

    ... 3350 is in a class of medications called osmotic laxatives. It works by causing water to be ... experience either of them, call your doctor immediately: diarrhea hives Polyethylene glycol 3350 may cause other side ...

  14. Structural changes in the polyethylene after ion implantation

    International Nuclear Information System (INIS)

    Proskova, K.; Svorcik, V.

    1999-01-01

    This work deals with the study of structural changes of the polyethylene after ion implantation. There were used the polyethylene film with thickness 15 μm, and Ar + ions with energy 63 keV and Xe + ions with energy 156 keV with doses 1·10 13 - 3·10 15 cm -2 for experiments. For the study of structural changes of polymer were used methods UV-VIS spectrometry, ESR, Rutherford back scattering

  15. Diffusive dynamics during the high-to-low density transition in amorphous ice

    Science.gov (United States)

    Perakis, Fivos; Amann-Winkel, Katrin; Lehmkühler, Felix; Sprung, Michael; Mariedahl, Daniel; Sellberg, Jonas A.; Pathak, Harshad; Späh, Alexander; Cavalca, Filippo; Schlesinger, Daniel; Ricci, Alessandro; Jain, Avni; Massani, Bernhard; Aubree, Flora; Benmore, Chris J.; Loerting, Thomas; Grübel, Gerhard; Pettersson, Lars G. M.; Nilsson, Anders

    2017-08-01

    Water exists in high- and low-density amorphous ice forms (HDA and LDA), which could correspond to the glassy states of high- (HDL) and low-density liquid (LDL) in the metastable part of the phase diagram. However, the nature of both the glass transition and the high-to-low-density transition are debated and new experimental evidence is needed. Here we combine wide-angle X-ray scattering (WAXS) with X-ray photon-correlation spectroscopy (XPCS) in the small-angle X-ray scattering (SAXS) geometry to probe both the structural and dynamical properties during the high-to-low-density transition in amorphous ice at 1 bar. By analyzing the structure factor and the radial distribution function, the coexistence of two structurally distinct domains is observed at T = 125 K. XPCS probes the dynamics in momentum space, which in the SAXS geometry reflects structural relaxation on the nanometer length scale. The dynamics of HDA are characterized by a slow component with a large time constant, arising from viscoelastic relaxation and stress release from nanometer-sized heterogeneities. Above 110 K a faster, strongly temperature-dependent component appears, with momentum transfer dependence pointing toward nanoscale diffusion. This dynamical component slows down after transition into the low-density form at 130 K, but remains diffusive. The diffusive character of both the high- and low-density forms is discussed among different interpretations and the results are most consistent with the hypothesis of a liquid-liquid transition in the ultraviscous regime.

  16. Low Density Symmetry Energy Effects and the Neutron Star Crust Properties

    International Nuclear Information System (INIS)

    Kubis, S.; Alvarez-Castillo, D.E.; Porebska, J.

    2010-01-01

    The form of the nuclear symmetry energy E s around saturation point density leads to a different crust-core transition point in the neutron star and affects the crust properties. We show that the knowledge of E s close to the saturation point is not sufficient to determine the position of the transition point and the very low density behaviour is required. We also claim that crust properties are strongly influenced by the very high density behaviour of E s , so in order to conclude about the form of low density part of the symmetry energy from astrophysical data one must isolate properly the high density part. (authors)

  17. Measurements of low density, high velocity flow by electron beam fluorescence technique

    International Nuclear Information System (INIS)

    Soga, Takeo; Takanishi, Masaya; Yasuhara, Michiru

    1981-01-01

    A low density chamber with an electron gun system was made for the measurements of low density, high velocity (high Mach number) flow. This apparatus is a continuous running facility. The number density and the rotational temperature in the underexpanding free jet of nitrogen were measured along the axis of the jet by the electron beam fluorescence technique. The measurements were carried out from the vicinity of the exit of the jet to far downstream of the first Mach disk. Rotational nonequilibrium phenomena were observed in the hypersonic flow field as well as in the shock wave (Mach disk). (author)

  18. Rendimento e qualidade do melão sob lâminas de irrigação e cobertura do solo com filmes de polietileno de diferentes cores Yield and fruit quality of melon cultivated under irrigation depths and coverage with polyethylene film of different colors

    Directory of Open Access Journals (Sweden)

    Maria Zuleide de Negreiros

    2005-07-01

    Full Text Available O experimento foi conduzido de abril a julho de 2002, na Fazenda Santa Júlia Agro-Comercial Exportadora de Frutos Tropicais Ltda, Mossoró, para avaliar o efeito da cobertura do solo com filmes de polietileno de diferentes cores (amarelo, marrom, preto, prateado e solo descoberto e lâminas de irrigação (100, 86 e 71% da lâmina padrão sobre o rendimento e qualidade do melão 'Gold Mine' cultivado na época chuvosa. O delineamento experimental utilizado foi o de blocos completos casualizados em esquema fatorial 5x3, com quatro repetições. Foram avaliados o número e produtividade de frutos comerciáveis, refugos e totais, massa média de frutos comercializáveis, classificação dos frutos, firmeza da polpa, espessura da polpa e teor de sólidos solúveis. Houve interação significativa entre os tipos de coberturas de solo e lâminas de irrigação para a massa média de frutos comercializáveis, com os filmes de polietileno registrando os maiores valores em relação ao solo descoberto. Os maiores rendimentos de frutos comercializáveis e totais, percentagens de frutos tipo exportação, teores de sólidos solúveis e espessura de polpa foram obtidos nas coberturas com filmes de polietileno. As lâminas de irrigação não afetaram de modo significativo a produção e qualidade dos frutos.The experiment was carried out during the period of April to July 2002 in the field, in Mossoró, Rio Grande do Norte State, Brazil, to evaluate the effect of soil coverages with polyethylene films of different colors (yellow, brown, black, silvered and no soil coverage and irrigation depths (100%, 86% and 71% of standard depth on fruit quality and yield of Gold Mine melon cultivated during rainfall season. The experiment was arranged in a 5 x 3 factorial, in randomized complete blocks design, with four replications. We evaluated the number and yield of commercial fruits, non-commercial and total fruits,fruit mean mass, fruit classification, pulp

  19. Indian meal moth (Plodia interpunctella)-resistant food packaging film development using microencapsulated cinnamon oil.

    Science.gov (United States)

    Kim, In-Hah; Song, Ah Young; Han, Jaejoon; Park, Ki Hwan; Min, Sea C

    2014-10-01

    Insect-resistant laminate films containing microencapsulated cinnamon oil (CO) were developed to protect food products from the Indian meal moth (Plodia interpunctella). CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to a low-density polyethylene (LDPE) film as an ink coating. The coated LDPE surface was laminated with a polypropylene film. The laminate film impeded the invasion of moth larvae and repelled the larvae. The periods of time during which cinnamaldehyde level in the film remained above a minimum repelling concentration, predicted from the concentration profile, were 21, 21, and 10 d for cookies, chocolate, and caramel, respectively. Coating with microencapsulated ink did not alter the tensile or barrier properties of the laminate film. Microencapsulation effectively prevented volatilization of CO. The laminate film can be produced by modern film manufacturing lines and applied to protect food from Indian meal moth damage. The LDPE-PP laminate film developed using microencapsulated cinnamon oil was effective to protect the model foods from the invasion of Indian meal moth larvae. The microencapsulated ink coating did not significantly change the tensile and barrier properties of the LDPE-PP laminate film, implying that replacement of the uncoated with coated laminate would not be an issue with current packaging equipment. The films showed the potential to be produced in commercial film production lines that usually involve high temperatures because of the improved thermal stability of cinnamon oil due to microencapsulation. The microencapsulated system may be extended to other food-packaging films for which the same ink-printing platform is used. © 2014 Institute of Food Technologists®

  20. Insect-resistant food packaging film development using cinnamon oil and microencapsulation technologies.

    Science.gov (United States)

    Kim, In-Hah; Han, Jaejoon; Na, Ja Hyun; Chang, Pahn-Sik; Chung, Myung Sub; Park, Ki Hwan; Min, Sea C

    2013-02-01

    Insect-resistant films containing a microencapsulated insect-repelling agent were developed to protect food products from the Indian meal moth (Plodia interpunctella). Cinnamon oil (CO), an insect repelling agent, was encapsulated with gum arabic, whey protein isolate (WPI)/maltodextrin (MD), or poly(vinyl alcohol) (PVA). A low-density polyethylene (LDPE) film was coated with an ink or a polypropylene (PP) solution that incorporated the microcapsules. The encapsulation efficiency values obtained with gum arabic, WPI/MD, and PVA were 90.4%, 94.6%, and 80.7%, respectively. The films containing a microcapsule emulsion of PVA and CO or incorporating a microcapsule powder of WPI/MD and CO were the most effective (P packaging for food products. The insect-repelling effect of cinnamon oil incorporated into LDPE films was more effective with microencapsulation. The system developed in this research with LDPE film may also be extended to other food-packaging films where the same coating platform can be used. This platform is interchangeable and easy to use for the delivery of insect-repelling agents. The films can protect a wide variety of food products from invasion by the Indian meal moth. © 2013 Institute of Food Technologists®