bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blends of ethylene–methyl acrylate–acrylic acid terpolymers with ethylene–acrylic acid copolymers: Mechanical and thermomechanical properties
Authors: Pongrakananon Nutthakan , Somrang Nathaporn , Visitsart Worakanya , Supaphol Pitt , Nithitanakul Manit , Grady Brian P. 
Published: December 2003

AbstractThe effect of methyl acrylate content in ethylene–methyl acrylate–acrylic acid (E–MA–AA) terpolymers and acrylic acid content in ethylene–acrylic acid (E–AA) copolymers was investigated in blends of these two materials. The E–MA–AA terpolymer with 8 mol % methyl acrylate was not miscible with any E–AA material no matter what the AA content, whereas the terpolymer with only about 2 mol % methyl acrylate was miscible, at least to some extent, with the E–AA copolymer at high acrylic acid contents. Evidence supporting this conclusion derived from gloss, differential scanning calorimetry testing, and dynamic mechanical measurements. For the E–AA polymer material with the highest acid content, there was a synergistic effect for some properties at low added amounts of E–MA–AA copolymer; the tensile strength and hardness were 10% higher than values for the E–AA copolymer, even though the E–AA copolymer was much stiffer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2216–2222, 2004
Phase‐separation phenomena in the polymerization of styrene in the presence of polyethylene wax
Authors: Liskova A. , Berghmans H. 
Published: December 2003

AbstractThe demixing processes that occur during the polymerization of styrene in the presence of a low molar mass polyethylene wax were investigated. Quantitative information on the phase behavior of such a three‐component system was obtained through the investigation of the temperature‐induced phase separation and the observation of the phase separation during polymerization. Both techniques allow the construction of the same ternary phase diagram. Such phase behavior can be understood through the discussion of the interference of a liquid–liquid phase‐separation process and crystallization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2234–2243, 2004
Heat‐treated softwood exposed to weathering
Authors: Nuopponen Mari , Wikberg Hanne , Vuorinen Tapani , Maunu Sirkka L. , Jämsä Saila , Viitaniemi Pertti 
Published: December 2003

AbstractScots pine samples, heat‐treated (225°C under steam) and reference (kiln‐dried), were exposed to natural weathering for 7 years in Espoo, Finland. The weathered and unweathered samples were examined with FTIR, UV resonance Raman, and 13C CPMAS NMR spectroscopies. The spectroscopic results revealed that the lignin contents of the weathered heat‐treated and especially of the weathered reference softwood samples diminished significantly. The surface of the weathered heat‐treated sample was still rich in aromatic and conjugated carbonyl structures, whereas the surface of the reference sample was enriched with cellulose. These results indicated that weathering products of lignin were leached out with water from the reference sample, whereas in the heat‐treated wood they were largely unleachable. The structure of the heat‐treated wood was modified and degradation products did not leach out as easily as in the case of the reference sample. The weathering also resulted in a decreased content of amorphous polysaccharides of the reference sample, whereas the changes in the polysaccharide contents between weathered and unweathered heat‐treated samples were not as dramatic because the amorphous carbohydrates were already degraded in the heat treatment. The results indicated that heat‐treated wood is more resistant to natural weathering than untreated wood. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2128–2134, 2004
Photooxidation and stabilization of photooxidized polyethylene and of its monopolymer blends
Authors: La Mantia F. P. , Tzankova Dintcheva N. 
Published: December 2003

AbstractThe increasing use of products from recycled polymers, or from blends with recycled polymers exposed to the outdoors, implies the need for good weathering resistance. This is particularly important when the recycled material comes, in turn, from products exposed during their lifetime to the sun. In this case the presence of CO groups in the macromolecular chains strongly increases the photooxidative degradation kinetics of these secondary materials. In this work the change of the photooxidative degradation of blends of virgin and photooxidized polyethylene was evaluated as a function of the CO content present in the material. As expected, the presence of the CO groups strongly increases the photooxidation kinetics, as revealed by the increase of the carbonyl compounds, and by the decrease of the elongation at break. It was confirmed that the increase of CO groups is dependent on the content of the same groups, whereas this is not true for the mechanical properties. The use of UV stabilizer strongly improves the weathering resistance of these materials, which become almost insensitive to the initial amount of CO groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2244–2255, 2004
The effect of methods of introducing acrylic emulsions grafted with acetoacetyl groups on the properties of particleboards
Authors: Dziurka Dorota , Łȩcka Janina 
Published: December 2003

AbstractThe aim of this study was to investigate the effect of compounds, either spread on particles or added to the resin, which contain various numbers of acetoacetyl groups in terms of their effect on formaldehyde content and the physical and mechanical properties of particleboards glued with the urea‐formaldehyde (UF) resin. The produced particleboards were subjected to the following European Standards standard tests: internal bond, modulus of rupture, modulus of elasticity, swelling in thickness after 24 h of soaking in water, and the content of formaldehyde. Results of the study make it possible to state that both the spreading of the acrylic emulsions containing acetoacetyl groups on the particles before gluing and the adding of them to the UF resin result in a decrease of formaldehyde content and improvement of physical and mechanical properties of particleboards. Boards with better properties were obtained in the case when emulsions containing acetoacetyl groups were spread directly on the surface of particles. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2256–2264, 2004
Density‐based phase‐separation asymmetric polyethylene–poly(dimethyl siloxane) blend membranes: Preparation and properties
Authors: Pandey Pratibha , Chauhan R. S. , Semwal R. P. , Banerjee S. , Jain Rajeev 
Published: December 2003

AbstractA new concept of density‐based phase separation for the preparation of asymmetric membranes from polyethylene (PE) blended with liquid poly(dimethyl siloxane) (PDMS) has been tried. The PE/PDMS membranes were prepared via high‐temperature solution casting. The purpose of incorporating PDMS was to utilize its flexibility, relatively high density in comparison with PE, and dissolution in common solvent for the formation of asymmetric PE/PDMS membranes. The study has been carried out with 1.25, 2.5, 5, and 10% (v/w) loading of PDMS. A host of techniques were used to study morphology of PE/PDMS blend membranes. The membranes show nodular structure on surfaces in contact with solvent vapor environment, whereas the opposite surfaces have smoother texture devoid of nodules. Although differential scanning calorimetric (DSC) melting endotherms indicate enhancement of crystallinity with PDMS addition, chemical etching and subsequent scanning electron microscopic (SEM) observations show increasingly ordered spherulitic pattern on individual nodules with the incorporation of PDMS up to 2.5%. The density of the films also increases with the addition of PDMS as compared to the control. ATR‐FTIR data revealed asymmetric distribution of PDMS in membranes with more PDMS retention toward lower surface of membranes. Membrane cross sections were indicative of graded porosity with increasing pore size toward the bottom surface of membranes. The results were explained in terms of density‐based phase separation.© 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91:2278–2287, 2004
Thermal degradation of the polyimide synthesized from 4,4′‐(hexafluoroisopropylidene) diphthalic dianhydride and 4,4′‐diaminodiphenylmethane
Authors: Ren Li , Fu Weiwen , Luo Yuanfang , Lu Hui , Jia Demin , Shen Jiarui , Pang Bei , Ko Tze‐Man 
Published: December 2003

AbstractThe thermal degradation of polyimide PIF2 synthesized from 4,4′‐(hexafluoroisopropylidene) diphthalic dianhydride and 4,4′‐diaminodiphenylmethane was systematically and thoroughly investigated by high‐resolution pyrolysis gas chromatography/mass spectrometry, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The pyrolyzates of PIF2 were dependent on the pyrolysis temperature. Two weight‐loss peaks were observed in the derivative thermogravimetric analysis of PIF2 and the first peak was related to the fluorine‐containing segment (hexafluoroisopropylidene). The overall activation energy and preexponential factor were calculated through dynamic TGA with Ozawa's method. Based on the results, a thermal degradation mechanism of the PIF2 was proposed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2295–2301, 2004
Electrochemical polymerization of fluoro‐ and chloro‐substituted anilines and copolymers with aniline
Authors: Şahin Yücel , Perçin Sabriye , Şahin Mutlu , Özkan Güleren 
Published: December 2003

AbstractPoly(2‐fluroaniline) and poly(2‐chloroaniline) were synthesized by an electrochemical method in an acetonitrile solution containing tetrabutylammonium perchlorate and perchloric acid. Also, the electrochemical copolymerization of aniline with 2‐fluroaniline and 2‐chloroaniline was carried out in the same medium. Cyclic voltammograms of the deposited films were recorded in neutral, acidic, and basic solutions. The electrochemical behavior of the films showed the same characteristic results as conventional polyaniline. The observed decrease in the dry electrical conductivity of the copolymers with respect to polyaniline was attributed to the incorporation of the fluoro‐ and chloro‐substituted anilines into the polyaniline chain. Further characterization of the polymer and copolymer products was performed through dry electrical conductivity measurements, ultraviolet–visible spectroscopy, and Fourier transform infrared spectroscopy. The relative solubility of the films was determined in various common organic solvents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2302–2312, 2004
Maleic anhydride grafted polypropylene as a coupling agent for polypropylene composites filled with ink‐eliminated waste paper sludge flour
Authors: Qiao Xiuying , Zhang Yong , Zhang Yinxi 
Published: December 2003

AbstractInk‐eliminated sludge flour (IESF), a waste residue from the recycling treatment of waste paper, is a promising new kind of filler for thermoplastic polymers with a good price/performance ratio and advantages for environmental protection. In this study, high‐impact polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were chosen as a polymer matrix and a coupling agent, respectively, for the preparation of IESF/PP composites, and the structures and properties of the obtained composites were also investigated. The experimental results revealed that IESF not only induced the crystallization orientation of PP along the b axis but also had a restraining effect on the formation of the β phase during the recrystallization of PP from the melt; the addition of MAPP further strengthened this effect to some extent. In addition, the proper addition of MAPP was helpful for improving the thermal stability of the IESF/PP composites. With the strengthening of the interfacial interaction between the IESF and PP matrix by MAPP, the resultant efficient stress transfer from the PP matrix to the IESF particles led to increased tensile and flexural strength. However, the original greater rigidity of MAPP, with respect to PP, reduced the toughness of the composites and caused some negative effects on the impact strength and the elongation at break. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2320–2325, 2004
Stability of high‐bandwidth graded‐index polymer optical fiber
Authors: Dai Xinhua , He Jun , Liu Zhimin , Ai Xicheng , Yang Guanying , Han Buxing , Xu Jian 
Published: December 2003

AbstractThe properties of poly(methyl methacrylate) (PMMA)‐based graded‐index polymer optical fiber (GI POF), including the thermal stability, thermal humidity, and mechanical properties, were studied for polymer optical fiber research and applications. The glass‐transition temperature of the fiber core was 103°C in the presence of the dopant, which was close to that of the PMMA matrix without the dopant. A special refractive‐index profile derived from the distribution of the dopant was stable at 60°C. Moreover, GI POF exhibited good mechanical properties. The excellent performance indicated that GI POF could be applied not only for indoor use but also for outdoor use. However, PMMA‐based GI POF exhibited poor hot‐water/humidity resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2330–2334, 2004
Ultraviolet curing of liquid polysulfide thiourethane acrylate
Authors: Quan Yi Wu , Dong Wen Zhao , Fang Jiang Ling , Chen Qing Min 
Published: December 2003

AbstractA series of liquid polysulfide thiourethane acrylate prepolymers were synthesized by the reaction of liquid polysulfide with isocyanate and hydroxyethyl acrylate. With and without a combination of acrylic monomers, the prepolymers were cured with ultraviolet radiation. The films exhibited a higher soft‐segment glass‐transition temperature than metal oxide cured polysulfide. With the addition of a diluent, the tensile strength and modulus increased, whereas the ultimate elongation decreased. The polysulfide backbone, combined with the crosslink generated from the photopolymerization of acrylic, produced films with superior oil resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2358–2363, 2004
Phase‐transfer‐agent‐aided polymerization and graft copolymerization of acrylamide
Authors: Kaur Inderjeet , Singh Baljit , Upasana  
Published: December 2003

AbstractThe use of phase‐transfer catalysts, with water‐insoluble initiators, for polymerization and graft copolymerization reactions was explored. The polymerization of a water‐soluble vinyl monomer, acrylamide (AAm), and the graft copolymerization of AAm onto a water‐insoluble polymer backbone, isotactic polypropylene (IPP), with a water‐insoluble initiator, benzoyl peroxide (BPO), and a phase‐transfer catalyst, tetrabutyl ammonium bromide (Bu4N+Br−), were carried out in a water/xylene binary solvent system. The conversion percentage of AAm into polyacrylamide (PAAm) and the percentage of grafting of AAm onto IPP were determined as functions of various reaction parameters, such as the BPO, AAm, and phase‐transfer‐catalyst concentrations, the amounts of water and xylene in the water/xylene mixture, the time, and the temperature. The graft copolymer, IPP‐g‐PAAm, was characterized with IR spectroscopy and thermogravimetric analysis. By a comparison of the results of the phase‐transfer‐catalyzed graft copolymerization of AAm onto IPP and the preirradiation method, it was observed that the optimum reaction conditions were milder for the phase‐transfer‐catalyst‐aided graft copolymerization. Milder reaction conditions, including the temperature, the time of reaction, and a moderate initiator (BPO), in comparison with high‐energy γ‐rays, led to better quality products, and the reaction proceeded smoothly with high productivity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2364–2375, 2004
Investigation of the influence of CuO filler and carbon fiber on wear and transfer film of nylon composites
Authors: Wang Jun‐Xiang , Gu Ming‐Yuan 
Published: December 2003

AbstractNylon 1010 composite specimens were prepared with CuO filler and short carbon fiber (CF) as the reinforcement. Friction and wear behavior of composite materials was investigated in a ring‐block wear tester. The results show that carbon fiber was more effective in reducing friction and wear of nylon than CuO filler. Nylon composite with 20% CF and 10% CuO content filler had the lowest wear rate that could not be obtained with any proportion of the fiber or the filler alone. It was found that the transfer film on the counterpart of 20% CF–10% CuO–nylon was thin, continuous, and uniform. These differences in tribological performance have been studied according to the synergism between the carbon fiber and CuO filler. The tribochemical studies by X‐ray photoelectron spectroscopy (XPS) revealed that pure Cu, Cu2O, and Cu(OH)2 were produced due to the decomposition of CuO during sliding. Carbon fiber promoted the process of tribochemical reactions of CuO, which generated more pure Cu particle and then self‐lubricating transfer film including pure Cu was formed on the steel counterpart.© 2003 Wiley Periodicals,Inc.J Appl Polym Sci 91: 2397–2401, 2004
Effect of organophilic montmorillonite on polyurethane/montmorillonite nanocomposites
Authors: Han Bing , Cheng Aimin , Ji Gending , Wu ShiShan , Shen Jian 
Published: December 2003

AbstractDifferent kinds of organophilic montmorillonite cotreated by cetyltrimethyl ammonium bromide (CTAB) and aminoundecanoic acid (AUA) were synthesized and applied to prepare polyurethane/montmorillonite nanocomposites via solution intercalation. The results of wide‐angle X‐ray diffraction (WAXD) and transmission electron microscopy showed that, for the montmorillonite modified with CTAB and CTAB/AUA (molar ratio of 1/2), an ordered intercalated nanostructure was derived, while for the montmorillonite treated with AUA, a disordered nanostructure was derived. The tensile properties of the polyurethane (PU) nanocomposites showed higher enhancement relative to PU matrix. TG showed that there is some enhancement in degradation behavior between the nanocomposites and PU matrix. DMTA results showed that nanocomposites from some organophilic montmorillonites showed a much higher storage modulus below and above glass transition temperature, while the nanocomposites from montmorillonite treated by AUA show an even lower storage modulus. The loss curves showed that the main glass transition temperature of PU was improved to some extent for the nanocomposites. The water absorption of PU and nanocomposites was also studied and the difference in reduction was thoroughly analyzed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2536–2542, 2004
Correlating the crystallization kinetics of syndiotactic polystyrene
Authors: Hieber C. A. 
Published: December 2003

AbstractThe Nakamura equation is used to model the crystallization kinetics of syndiotactic polystyrene. Model constants are generated by fitting available data under isothermal conditions. The resulting fit is then applied to available data under constant‐cooling‐rate conditions, with notable agreement provided the measurements include corrections for thermal lag. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2402–2406, 2004
Study on the structure and processibility of the iodinated poly(vinyl alcohol). I. Thermal analyses of iodinated poly(vinyl alcohol) films
Authors: Shin Eun Joo , Lee Yang Hun , Choi Suk Chul 
Published: December 2003

AbstractTo get more information on the structure of iodinated poly(vinyl alcohol) (PVA), thermal analyses of unoriented and oriented PVA films were conducted. Unoriented and oriented PVA films iodinated with aqueous solutions at selected concentrations were carried out by thermogravimetry (TG) and differential scanning calorimetry (DSC). The TG curves for the iodinated film shows four or five weight‐loss zones associated with degradation and evaporation of excess I2 molecules and I2 molecules from I, partial OH side groups on PVA, and I2 from I, the remaining OH groups and the partial main chains, the remaining main chains, and a very small amount of residue from PVA. The char of KI salts remained. By investigating the TG results, it was identified that the amount of I ions increased with increasing I2/KI up to 65%, but above that weight gain, the rate of increase diminished and the amount of I ions from the I ions increased. The TG curve for the oriented film was very similar to that for the unoriented film except for its greater weight loss at zone I due to narrow space in amorphous region. The DSC thermogram of iodinated films indicated two peaks at 145°C and 160–170°C, corresponding to the melting of crystals and the degradations of OH groups and main chains, respectively. The maximum temperatures of peaks were much lower than that of the untreated one. ©2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2407‐2415, 2004
Study of sulfonation mechanism of low‐density polyethylene films with fuming sulfuric acid
Authors: Kaneko Masashi , Kumagai Satoshi , Nakamura Tatsuo , Sato Hisaya 
Published: December 2003

AbstractSulfonation of low‐density polyethylene (LDPE) films with fuming sulfuric acid was studied by X‐ray photoelectron spectroscopy (XPS) and attenuated total reflectance (ATR) infrared spectroscopy. The ATR spectra showed the formation of CC double bonds and multiple sulfur atom containing groups for the sulfonation of LDPE films. This led us to propose that the abstraction reaction of hydride ion by sulfur trioxide (SO3) in fuming sulfuric acid might account for the formation of the CC double bonds. It was considered that after the abstraction reaction, these double bonds react with SO3, resulting in the production of alkene sulfonic acids and sultones, along with the formation of sulfate groups as a result of reaction of the double bonds with sulfuric acid. Experimental data by treatment of the sulfonated LDPE films with KOH and thiourea supported the proposed idea, estimating the approximate molar ratio of the products. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2435–2442, 2004
Thermal properties of wood reacted with a phosphorus pentoxide–amine system
Authors: Lee Hong‐Lin , Chen George C. , Rowell Roger M. 
Published: December 2003

AbstractThe objective of this research was to improve the fire‐retardant properties of wood in one treatment using a phosphorus pentoxide–amine system. Phosphorus pentoxide and 16 amines including alkyl, halophenyl, and phenyl amines were compounded in N,N‐dimethylformamide and the resulting solutions containing phosphoramides were reacted with wood. The characteristics of phosphoramide‐reacted wood were analyzed by FTIR, energy‐dispersive X‐ray analysis, and elemental analysis. Fire retardancy of phosphoramide‐reacted woods was evaluated by DSC and thermogravimetric analysis (TGA). DSC demonstrated that the modification can lower the onset of an endotherm and decrease the heat of combustion and heat flow. TGA showed that most of the phosphoramide‐reacted woods had higher char yields than that of wood impregnated with diammonium phosphate.© 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2465–2481, 2004
Adsorption behavior of poly(N,N‐dimethylacrylamide‐co‐na 2‐acrylamido‐2‐methylpropanesulfonate) on sand surface
Authors: Sabhapondit Anupom , Borthakur Arun , Haque Inamul 
Published: December 2003

AbstractThe adsorption behavior of poly(N,N‐dimethylacrylamide‐co‐Na 2‐acrylamido‐2‐methylpropanesulfonate), an enhanced oil recovery polymer, was studied. Adsorption isotherms show that adsorption on bentonite is very high followed by that on limestone that, in turn, is much higher than that on sand surface following the order: bentonite ≫ limestone > sand. On the addition of NaCl, adsorption on sand surface decreased to a minimum value and then increased. Adsorption increased with decreasing pH and also decreasing the content of Na 2‐acrylamido‐2‐methylpropanesulfonate in the copolymer. The amount of the copolymer adsorbed on the sand surface is comparable to that of partially hydrolyzed polyacrylamide but much less than that of poly(acrylamide‐co‐vinylpyrrolidone). The type of adsorption was found to be physical, which is supported by the enthalpy of adsorption as well as by IR spectra. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2482‐2490, 2004