bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physicochemical properties of irradiated and loaded LDPE films with polyfunctional monomers
Authors: Ali Z. I. , Youssef H. A. , Saleh H. H. , Zahran A. H. 
Published: June 2003

AbstractPolyfunctional monomers (PFMs), namely, trimethylol propane trimethacrylate (TMPTMA), trimethylol propane triacrylate, ethylene glycol dimethacrylate, and diethylene glycol diacrylate were blended with low‐density polyethylene (LDPE) and exposed to different doses of EB irradiation. Fourier transform infrared and ultraviolet and UV–vis spectroscopy of the unirradiated, irradiated, unloaded, and PFMs‐loaded LDPE films were studied under various irradiation doses up to 300 kGy. The degree of crosslinking and oxidative degradation, as measured by the spectroscopic parameters, were dependent on both the irradiation dose and the type of loaded PFMs. For all of the loaded monomers, the extent of crosslinking increased at different rates as a function of irradiation dose. TMPTMA monomer was the most efficient in enhancing the crosslinking of LDPE films compared to the other loaded monomers. However, the unloaded LDPE film showed the least extent of crosslinking. In addition, the EB‐radiation‐induced changes, such as trans‐vinylene formation, a decrease in vinyl and vinylidene unsaturation; and carbonyl double‐bond formation and change in crystallinity were correlated. The importance of these results on the prediction of the role of polyfunctional monomers in the production of crosslinked polymers is discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2025–2035, 2003
Polymorphism in intercalated poly(vinylidene fluoride)/clay nanocomposites
Authors: Priya L. , Jog J. P. 
Published: June 2003

AbstractPolymorphism in poly(vinylidene fluoride) (PVDF)/clay nanocomposites was studied. Poly(vinylidene fluoride)/clay nanocomposites were prepared with melt intercalation. The samples were characterized with X‐ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy. The nanocomposite exhibited the β form. Thermal annealing performed at 125 and 185°C showed that the β form of PVDF was stable. The stability of the β form of PVDF was ascertained from these studies. The β form of PVDF in the nanocomposites could be due to crystallization in the constrained phase. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2036–2040, 2003
Poly(sulfobetaine)s and corresponding cationic polymers. XI. Synthesis and aqueous solution properties of a cationic poly(methyl iodide quaternized ethyl vinyl ether/N,N‐dimethylaminopropyl maleamidic acid) copolymer
Authors: Lee Wen‐Fu , Chen Yan‐Ming 
Published: June 2003

AbstractA copolymer prepared by the copolymerization of ethyl vinyl ether and maleic anhydride underwent amidoacidation with N,N‐dimethylaminopropylamine. The obtained ethyl vinyl ether/dimethylaminopropyl maleamidic acid copolymer was then reacted with methyl iodide to yield poly(methyl iodide quaternized ethyl vinyl ether/N,N′‐dimethylaminopropyl maleamidic acid) (MIQEDMAPMA). The greatest difference from other polyelectrolytes was the carboxylic group on the polymer chain unit of MIQEDMAPMA. Its aqueous solution properties in various salts and at various pH values were studied by measurements of the reduced viscosity and intrinsic viscosity. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentrations of the added salts. The tendency of the salt effect was similar to that of other polyelectrolytes; that is, soft salt anions were more easily bound to the quaternary ammonium (R4N+) of MIQEDMAPMA than hard salt anions. Some salt ions strongly attracted the quaternary ammonium of the cationic polymeric side chain for the agglomeration of the polymers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2261–2269, 2003
Highly efficient flocculant synthesized through the dispersion copolymerization of water‐soluble monomers induced by γ‐ray irradiation: Synthesis and polymerization kinetics
Authors: Ye Qiang , Zhang Zhicheng , Ge Xuewu 
Published: June 2003

AbstractA water‐soluble cationic copolymer dispersion was prepared by the polymerization of the cationic monomer (2‐methacryloyloxyethyl)trimethyl ammonium chloride and acrylamide initiated with60Co γ‐rays. The polymerization was carried out in a salt solution that did not dissolve the resulting copolymer and in the presence of a polymeric dispersant that was soluble in the salt solution. The polymerization conversion was studied gravimetrically. The bulk viscosity of the copolymer dispersion was determined with a rotation viscometer. The intrinsic viscosity of the copolymer was measured viscometrically, and the particle size was determined with an optical microscope. The influence of some conditions on the copolymerization was studied, including the irradiation dose, dose rate, concentrations and compositions of the monomers, dispersant content, and types and contents of the inorganic salts. The flocculating characteristics of a synthetic cationic copolymer dispersion were also briefly investigated. The optimal conditions for polymerization were summarized, and some aspects of the polymerization mechanisms were examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2108–2115, 2003
Physical properties of polyethylene/silicate nanocomposite blown films
Authors: Hyun Ki , Chong Wang , Koo Min , Chung In Jae 
Published: June 2003

AbstractMaleated polyethylene/silicate nanocomposite and maleated polyethylene/SiO2 blown films were prepared by melt extrusion. The silicate and SiO2 significantly affected the physical properties of the films. The former films showed higher tensile strength than the latter films. This high reinforcement effect seemed to be attributable to the strong interaction between the matrix and silicate as well as the uniform dispersion of silicate layers in the polymer matrix. The addition of silicate beyond a certain content gave a worse Elmendorf tear strength than SiO2. The silicate did not increase the falling dart impact strength at all. The worst Elmendorf strength apparently originated from the orientation of anisotropic silicate rather than the orientation of lamellae of the polymer matrix, and the silicate made the films more brittle. The well‐dispersed silicate layers in the polymer matrix gave almost the same optical properties as the pure polymer despite the increase in the silicate content. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2131–2136, 2003
Crystallization behavior, mechanical properties, and environmental biodegradability of poly(β‐hydroxybutyrate)/cellulose acetate butyrate blends
Authors: Wang Tiezhu , Cheng Guoxiang , Ma Shihu , Cai Zhijiang , Zhang Liguang 
Published: June 2003

AbstractThe miscibility, crystallization behavior, tensile properties, and environmental biodegradability of poly(β‐hydroxybutyrate) (PHB)/cellulose acetate butyrate (CAB) blends were studied with differential scanning calorimetry, scanning electron microscopy, wide‐angle X‐ray diffraction, and polarizing optical microscopy. The results indicated that PHB and CAB were miscible in the melt state. With an increase in the CAB content, the degree of crystallinity and melting temperature of the PHB phase decreased, and this broadened the narrow processability window of PHB. As the elongation at break increased from 2.2 to 7.3%, the toughness and ductility of PHB improved. From the degradation test, it could be concluded that degradation occurred gradually from the surface to the inside and that the degradation rate could be adjusted by the addition of the CAB content. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2116–2122, 2003
Effects of rosin‐type cocrystal nucleating agents on the crystallization process and the properties of polypropylene
Authors: Wang Hui , Li Chun‐Cheng , Zhang Dong , Li Zhen‐Yi 
Published: June 2003

AbstractA new kind of rosin‐type nucleating agent for polypropylene (PP), the cocrystal of dehydroabietic acid, potassium dehydroabietate, and sodium dehydroabietate, was prepared, and the effects of the nucleating agents on the mechanical and crystallization properties of PP were also studied. The results of differential scanning calorimetry and X‐ray diffraction proved that the cocrystal of dehydroabietic acid and compound alkali dehydroabietate was formed rather than a simple blend of dehydroabietic acid and single alkali dehydroabietate. When it was added to PP, the size of the PP spherulite decreased; the mechanical properties, crystallization temperature, and transparency of PP were substantially improved. Thus, the cocrystal of dehydroabietic acid, potassium dehydroabietate, and sodium dehydroabietate acted as a more effective nucleating agent for PP. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2137–2141, 2003
Thermal and morphological studies of chemically prepared emeraldine‐base‐form polyaniline powder
Authors: Chen Cheng‐Ho 
Published: June 2003

AbstractIn this study, emeraldine base (EB)‐form polyaniline (PANI) powder was chemically prepared in 1M HNO3 aqueous solution. The thermal characteristics and chemical structures of this powder were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD). A polarizing optical microscope was also used to examine the crystalline morphology of this sample. The results indicated that the EB‐form PANI powder had a discernible moisture content. Moreover, in the first run of DSC thermal analysis, the exothermic peak at 170–340°C was due to the crosslinking reaction occurring among the EB‐form PANI molecular chains. FTIR and XRD examinations further confirmed the chemical crosslinking reaction during thermal treatment. TGA results illustrated that there were two major stages for weight loss of the EB‐form PANI powder sample. The first weight loss, at the lower temperature, resulted from the evaporation of moisture. The second weight loss, at the higher temperature, was due to the chemical structure degradation of the sample. The degradation temperature of the EB‐form PANI powder was around 420–450°C. The degradation temperature of emeraldine salt (ES)‐form PANI powder was lower (around 360–410°C) than that of the EB form (around 420–450°C). From the TGA results, I roughly estimated that 2.74 aniline repeat units, on average, were doped with 1 HNO3 molecule in the ES‐form PANI. I found a single crystalline morphology of EB‐form PANI, mostly like a conifer leaf. More complex, multilayered dendritic structures were also found. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2142–2148, 2003
Highly thermally conductive room‐temperature‐vulcanized silicone rubber and silicone grease
Authors: Wang Qian , Gao Wei , Xie Zemin 
Published: June 2003

AbstractIn this study, the effects of thermally conductive filler type (α‐Al2O3, SiC), volume fraction of the filler, and filler particle size distribution on the thermal conductivity and viscosity of room‐temperature‐vulcanized (RTV) silicone rubber and silicone grease were investigated. We were interested to find that silicone grease (or the RTV silicone rubber) had a maximum thermal conductivity (∼1.48 W/mK) and a minimum viscosity (∼3.4 × 104 mPa s), with a definite total volume fraction of the filler (0.55) when the distribution of filler sizes (the number ratio of two different particles sizes, i.e., 0.8 and 6 μm) was 600–700. We were able to increase the thermal conductivity of the RTV silicone rubber and silicone grease beyond 2 W/mK by increasing the total volume fraction of the filler with adequate filler size distributions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2397–2399, 2003
Thermodynamic theory of the viscoelasticity and yield of glassy polymers: Internal time theory
Authors: Cho Kwang Soo , Kim Sang Yong 
Published: June 2003

AbstractA nonlinear viscoelastic constitutive equation of glassy polymers has been developed on the basis of the internal time and irreversible thermodynamics of internal variables. The constitutive equation is a generalization of spring–dashpot models and describes the yield behavior of glassy polymers. With this constitutive equation, the rate of entropy production has been determined to show a peak near the yield. We propose a new yield criterion, that yield occurs at the maximum rate of entropy production. The yield criterion is almost equivalent to that of peak stress and a thermodynamic interpretation of yield. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2400–2411, 2003
Preparation of magnetic ion‐exchange resins by the suspension polymerization of styrene with magnetite
Authors: Lee Yonghoon , Rho Joonho , Jung Bumsuk 
Published: June 2003

AbstractMagnetic polymer microspheres composed of magnetite, styrene, and divinylbenzene were prepared by suspension polymerization to produce magnetic ion‐exchange resins (MIEXs). The magnetite was grafted with oleic acid to improve the magnetic properties of the MIEXs and to prevent the magnetite from flushing out of the MIEXs. The shape and magnetic properties of the magnetic microspheres were investigated with scanning electron microscopy and vibrating‐sample magnetometry. The average diameter of the prepared magnetic polymer microspheres was about 219 μm. The two types of MIEXs were prepared, magnetic cation‐exchange resins (MCEXs) and magnetic anion‐exchange resins (MAEXs). MCEX was prepared by sulfonation of magnetic polymer microspheres, and MAEX was made by a quaternization reaction with triethylamine of chloromethylated magnetic polymer microspheres. With diffuse‐reflectance Fourier transform infrared spectroscopy, elemental analysis, and acid–base titration, the degree of substitution and ion‐exchange capacity of the MIEXs were assessed. The efficiency of each MCEX and MAEX for the purification of contaminated water was examined with Co2+ and NO solutions, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2058–2067, 2003
Syntheses of hydroxypropyl methylcellulose phthalate hydrogels in Na2CO3 aqueous solutions with electron‐beam irradiation
Authors: Xu Ling , Nagasawa Naotsugu , Yoshii Fumio , Kume Tamikazu 
Published: June 2003

AbstractNovel cellulose ether hydrogels were prepared by the radiation‐induced crosslinking of hydroxypropyl methylcellulose phthalate (HPMCP) in a solution of Na2CO3. The effects of several factors, such as the HPMCP concentration, Na2CO3 concentration, absorbed dose, and dose rate, on the crosslinking of HPMCP were investigated in detail. An increase in the HPMCP concentration resulted in an increasing content of the gel fraction, and this meant that the crosslinking probability increased as well. Na2CO3 was essential for dissolving HPMCP in water, and a 4–5% Na2CO3 aqueous solution was optimal for the crosslinking of HPMCP. The dose rate also affected the radiation crosslinking of HPMCP; hydrogels with higher gel fractions and transparency could be formed at lower dose rates. The ratio of degradation to crosslinking of the gel was calculated according to the Charlesby–Rosiak equation, and it showed good agreement with the experimental results. Some important properties, such as the swelling kinetics, ion and ionic strength dependence, and pH dependence, of the HPMCP hydrogels were also investigated. The HPMCP hydrogels possessed excellent swelling rates and swelling ratios in some solvents, such as water and methanol, with a high hydrogen‐bonding parameter. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2123–2130, 2003
Effect of reaction kinetics of polymer electrolyte on the ion‐conductive behavior for poly(oligo oxyethylene methacrylate)–LiTFSI mixtures
Authors: Kwak Gun‐Ho , Tominaga Yoichi , Asai Shigeo , Sumita Masao 
Published: June 2003

AbstractThe effect of the reaction kinetics on the ionic conductivity for a comblike‐type polyether (MEO) electrolyte with lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) was characterized by DSC, complex impedance measurements, and 1H pulse NMR spectroscopy. The ionic conductivity of these electrolytes was affected by the reaction condition of the methacrylate monomer and revealed by the glass transition temperature (Tg), spin–spin relaxation time (T2), steric effects of the terminal groups, and the number of charge carriers indicated by the VTF kinetic parameter. In this system, the electrolytes prepared by the reaction heating rate of 10°C/min of MEO–H and 15°C/min of MEO–CH3 showed maximum ionic conductivity, σi, two to three times higher in magnitude than that of the σi of the others at room temperature. As experimental results, the reaction kinetic rate affected the degree of conversion, the ionic conductivity, and the relaxation behaviors of polyether electrolytes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2149–2156, 2003
Synthesis and characterization of novel copper/polyaniline nanocomposite and application as a catalyst in the Wacker oxidation reaction
Authors: Athawale Anjali A. , Bhagwat S. V. 
Published: June 2003

AbstractCopper nanoclusters were synthesized by a chemical reduction of an aqueous copper salt solution by sodium borohydride. A polyaniline nanocomposite containing copper nanoclusters was prepared by polymerizing a monomer aniline hydrochloride solution containing the copper nanoclusters using ammonium persulfate as an oxidizing agent. The synthesized nanocomposite was characterized using various techniques such as UV‐visible spectroscopy, FTIR spectroscopy, X‐ray diffraction (XRD), and transmission electron microscopy (TEM). The presence of copper was confirmed by XRD and the size of the copper clusters was found to be ∼53 nm, which is in good agreement with that obtained from the TEM. The synthesized nanocomposite was used to serve as a catalyst in a Wacker oxidation reaction for the conversion of 1‐decene to 2‐decanone in the presence of molecular oxygen. The formation of 2‐decanone was confirmed using GC‐MS. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2412–2417, 2003
Effect of nitrocellulose on the properties of PU–NC semi‐IPN wood coatings
Authors: Lu Kun‐Tsung , Liu Cheng‐Tzu , Lee Hong‐Lin 
Published: June 2003

AbstractWood coatings of PU–NC semi‐interpenetrating polymer networks (semi‐IPNs), made from blown castor oil (BCO), aromatic polyisocyanate (PTDI), and nitrocellulose (NC), were prepared by sequential polymerization method. To investigate the effects of NC on the properties of PU–NC semi‐IPNs wood coatings, three different viscosities of NC (½‐sec, ¼‐sec, and
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‐sec), and a PU catalyst [dibutyltin dilaurate (DBTDL)] were synthesized in this study. The results revealed that the PU–NC semi‐IPNs with ½‐sec NC‐containing coating had the shortest drying time, and their films had the best tensile strength, elongation at break, lightfastness, and solvent resistance. Dynamic mechanical analysis showed that PU–NC semi‐IPNs with ½‐sec NC or
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‐sec NC had good interpenetration between PU and NC, whereas PU–NC semi‐IPNs with ¼‐sec NC had a slight separation phase between PU and NC. In both PU–NC semi‐IPNs with ¼‐sec NC and those with \documentclass{article}\pagestyle{empty}\begin{document}${1\over 16}$\end{document}
‐sec NC, the addition of 0.2% DBTDL could effectively reduce the drying time of the coating and improve the film properties, including tensile strength, elongation at break, and lightfastness. In addition, the miscibility of PU and NC was examined in PU–NC semi‐IPNs with ¼‐sec NC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2157–2162, 2003
Mobility and solubility of antioxidants and oxygen in glassy polymers. I. Concentration and temperature dependence of antioxidant sorption
Authors: Boersma Arjen 
Published: June 2003

AbstractSorption experiments have been conducted at temperatures between 65 and 135°C using five phenolic antioxidants in polycarbonate at different antioxidant concentrations. A model based on the free volume was used to predict the mobility of the additives. In this model, the ratio of the specific volume of a jumping unit to the free volume available in the polymer determines the diffusion behavior of the additives. It was found that the mobility of the antioxidant was predicted accurately using literature and experimental data on the free volume in polycarbonate. Furthermore, the solubility of the antioxidants was predicted very well, based on thermodynamic considerations. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2163–2178, 2003
Synthesis and solution properties of single‐chain microgels from poly(N‐isopropylacrylamide) copolymer
Authors: Zhou Nan , Ni Jian , Yan Xiaohu , Wang Zhiliu , Cheng Rongshi 
Published: June 2003

Abstract“Single‐chain” microgels were synthesized successfully from the cross‐linkable poly(N‐isopropylacrylamide) (PNIPAM) copolymer. This type of microgel has the exact chemical structure, molecular weight and molecular weight distribution of its precursor. It provides a direct way to compare the properties of linear polymers with those of their networks. The viscosity properties show that the microgels have lower critical solution temperatures (LCST) that are even higher than those of the corresponding linear copolymers. This can be attributed to the crosslinking points, which retard the change of the conformation of the network chains. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2179–2183, 2003
Effect of epoxy resin on morphology and physical properties of PVC/organophilic montmorillonite nanocomposites
Authors: Wan Chaoying , Qiao Xiuying , Zhang Yong , Zhang Yinxi 
Published: June 2003

AbstractPoly(vinyl chloride)/organophilic montmorillonite (PVC/OMMT) nanocomposites were prepared by means of melt blending. A liquid epoxy resin was used to aid PVC chains in intercalating into silicate layers. The effects of the preparation methods and epoxy resin contents on the melt intercalation of PVC were investigated. The morphology development, mechanical properties and optical properties of the PVC/OMMT composites were tested as functions of epoxy resin content and OMMT content. Wide‐angle X‐ray diffraction, transmission electron microscopy and scanning electron microscopy were used to characterize the morphology of the resulting composites. After being pretreated by the epoxy resin, the OMMT layers were largely intercalated into the PVC matrix, and even exfoliated at high epoxy resin content. The addition of epoxy resin led to a decrease in optical clarity of the composites but improved the processing stability, as indicated by yellowness index and haze measurement. However, the optical clarity of the composites containing 4 phr of epoxy resin (PVC/E‐OMMT) was improved by increasing the OMMT content, as shown by light transmission. Both the tensile strength and notched Izod impact strength of the PVC/E‐OMMT composites reached their maximum values when the OMMT content was 0.5 phr and the epoxy resin content was 2 phr. With further increase of the OMMT content and the epoxy resin content, the tensile strength decreased but was still higher than that of original PVC. The method of addition of epoxy resin had little effect on the physical properties but mainly influenced the morphology of PVC/OMMT nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2184–2191, 2003