bluuebunny/crossref_metadata_2025_split huggingface dataset:
Absorption of trioctyl trimellitate into mass‐polymerization and suspension‐polymerization poly(vinyl chloride)
Authors: Luo Yuxiang , Dai Gance 
Published: April 2004

AbstractPoly(vinyl chloride) (PVC) slush powder has been widely used; we prepared it by dry blending. We found that the absorption of plasticizer by the PVC resins was the most important factor in the dry‐blending process and, further, that different types of PVC resin had different absorption rates. This results of this study provide new information about the relationship of absorption to PVC and other parameters. Haake rheomix testing and the quantity of plasticizers absorbed by the PVC resins were used to characterize the absorption process. Suspension‐polymerization poly(vinyl chloride) (SPVC) and mass‐polymerization poly(vinyl chloride) (MPVC) in different sizes were used for the test. The results showed that the MPVC absorbed the plasticizer more quickly than SPVC, especially at a higher temperature. However, for the same PVC resin type, the absorbing speeds were nearly independent of particle size. The studies that used a scanning electric microscope and specific surface area revealed that the morphology of the two types of particles was different. The surfaces of the individual particles of SPVC were smoother than those of MPVC. There was a “skin” covering the SPVC particles, whereas with the MPVC particles, the primary polymer was exposed directly on the surface. This difference in morphology was shown to be a significant factor in the different rates of absorption of the plasticizers for the different PVC resins. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2369–2374, 2004
Advances in stereolithography: A new experimental technique in the production of a three‐dimensional plastic model with an infrared laser
Authors: Jardini A. L. M. , Maciel R. F. , Scarparo M. A. F. , Andrade S. R. , Moura L. F. M. 
Published: April 2004

AbstractThe development of a new approach for the production of three‐dimensional plastic parts, called infrared laser stereolithography, is presented. During the experimentation, a carbon dioxide (CO2) laser beam at 10.6 μm (infrared radiation) was focused on a sample composed of an epoxy resin, diethylene triamine (curing agent), and silica powder (filler). The CO2 laser, adopted for cost reduction, led to no significant shrinkage, and almost no postcure treatment was required. With differential scanning calorimetry, it was possible to determine the reaction rate as a function of the temperature and the activation energy of the curing process. The solution of the heat equation, with the Ansys program simulating this process, was in general agreement with our previous observations of the stereolithography results. The experimental results of the production of solid parts layer by layer in three dimensions are presented. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2387–2394, 2004
Synthesis and characterization of new soluble poly(ester‐imide)s containing noncoplanar 2,2′‐dimethyl‐4,4′‐biphenylene unit
Authors: Liaw Der‐Jang , Fan Chi‐Lung , Lin Chi‐Cheng , Wang Kun‐Li 
Published: April 2004

AbstractA new diimide–diacid chloride (3) containing a noncoplanar 2,2′‐dimethyl‐4,4′‐biphenylene unit was synthesized by treating 2,2′‐dimethyl‐4,4′‐diamino‐biphenylene with trimellitic anhydride followed by refluxing with thionyl chloride. Various new poly(ester‐imide)s were prepared from 3 with different bisphenols by solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher at 170°C. Inherent viscosities of the poly(ester‐imide)s were found to range between 0.31 and 0.35 dL g−1. All of the poly(ester‐imide)s, except the one containing pendent adamantyl group 5e, exhibited excellent solubility in the following solvents: N,N‐dimethylformamide, tetrahydrofuran, tetrachloroethane, dimethyl sulfoxide, N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidinone, m‐cresol, o‐chlorophenol, and chloroform. The polymers showed glass‐transition temperatures between 166 and 226°C. The 10% weight loss temperatures of the poly(ester‐imide)s, measured by TGA, were found to be in the range between 415 and 456°C in nitrogen. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2486–2493, 2004
Melt grafting of 10‐undecenoic acid onto linear low density polyethylene
Authors: Ciolino A. , Vallés E. M. , Failla M. D. 
Published: April 2004

AbstractThe melt grafting of 10‐undecenoic acid (UA) onto a linear low‐density polyethylene (LLDPE) was studied. The grafting reaction was performed in a thermoplastic mixer and 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy) hexane was used as initiator. The concentration of UA and peroxide ranged from 1 to 4% (w/w) and 0.025 to 0.1% (w/w), respectively. Evidence of the grafting of UA as well as its extent was determined by FTIR. Experimental results showed that the amount of UA grafted increases with both the UA and initiator concentrations. However, the greatest efficiency of grafting was found at the lowest concentration of UA investigated. The grafting efficiency ranged from 8 to 40%. The dynamic linear viscoelastic properties of the original polymer and the grafted materials were evaluated at different frequencies at 160°C using a dynamic rotational rheometer. The modification process affected the melt elasticity and viscosity of the LLDPE. When the original polymer was modified only with peroxide both properties increased with respect to those of the original material. However, when UA was grafted onto LLDPE, the resulting polymers displayed values of elastic moduli and viscosity lower than those of the polymer modified with peroxide. Moreover, when a concentration of 4% of UA was used, the values of those properties were even lower than those corresponding to the original LLDPE. These observations combined with the data obtained from the GPC results suggest that scission reactions may be favored by the presence on UA. In contrast with previous observations, the thermal properties measured by DSC were only slightly altered. The fusion temperature of the modified polymers was slightly lower than that corresponding to the original polymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2303–2311, 2004
Mechanism study on surface activation of surfactant‐modified polyvinyl siloxane impression materials
Authors: Lee Doug‐Youn , Oh Young‐Il , Chung Kyung‐Ho , Kim Kwang‐Mahn , Kim Kyoung‐Nam 
Published: April 2004

AbstractThis study examined the mechanism on the surface activation of hydrophilic polyvinyl siloxane impression materials incorporated with nonionic surfactants. Hydrophilic polyvinyl siloxane impression materials were prepared with a polydimethylsiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into polyvinyl siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of polyvinyl siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant‐modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
Reduction of offensive odor from natural rubber by odor‐reducing substances
Authors: Hoven Vipavee P. , Rattanakarun Kesinee , Tanaka Yasuyuki 
Published: April 2004

AbstractA number of chemicals including carbon black, chitosan, benzalkonium chloride, sodium dodecyl sulfate, cyclodextrin, and zeolite13x were tested as odor‐reducing fillers. The rationale is based on the concept of using odor absorbents/adsorbents for which both physical adsorption and chemical adsorption play an important role in odor reduction. The fillers were incorporated into highly odorous natural rubber (STR20 and RSS5) by physical mixing prior to sulfur vulcanization. As identified by gas chromatography and gas chromatography/mass spectrometry, the unpleasant odor mainly originates from low molecular weight volatile fatty acids. The quantity of acetic acid, a representative of odor molecule, can be significantly reduced in the presence of chitosan and zeolite13x. Although carbon black and cyclodextrin exhibited a tendency to reduce the odor, they were not as effective as zeolite13x and chitosan. On the other hand, commercial surfactants such as benzalkonium chloride and sodium dodecyl sulfate cannot serve as odor‐reducing substances because of their limited thermal stability. An olfactometry test confirmed that chitosan and carbon black are good odor‐reducing agents. Chitosan and carbon black showed a reinforcing effect on vulcanized rubber, whereas the surfactant deteriorated the strength of the rubber composite. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2253–2260, 2004
Investigation of ZnO‐release behavior of poly(N‐isopropylacrylamide‐co‐maleic acid)/ZnO composite hydrogels by differential pulse polarography
Authors: İnam Recai , Çaykara Tuncer , Akkoç Sibel , Kantoğlu Ömer 
Published: April 2004

AbstractPoly(N‐isopropylacrylamide‐co‐maleic acid)‐zinc oxide [P(NIPA/MA)/ZnO] composite hydrogels, containing a definite amount of ZnO, were prepared from N‐isopropylacrylamide (NIPA) and maleic acid (MA) monomers with 0–31.15 mol % MA in aqueous saturated zinc oxide solutions by radiation‐induced polymerization and gelation using γ rays from a 60Co source. The amounts of released ZnO from these composite hydrogels were determined by differential pulse polarography (DPP) using the characteristic peaks obtained at about –1,000, −1,050, and –1,300 mV at pH 2.0, 5.5, and 7.05, respectively. It was found that the ZnO‐release behavior of P(NIPA/MA)/ZnO composite hydrogels depended strongly on the MA content and pH of the medium.
The study of poly(styrene‐co‐p‐(hexafluoro‐2‐hydroxylisopropyl)‐α‐methylstyrene)/poly(ethylene oxide) blends
Authors: Chen Shiming , Qiu Furong , Tan Li 
Published: April 2004

AbstractDifferent hydroxyl content poly(styrene‐co‐p‐(hexafluoro‐2‐hydroxylisopropyl)‐α‐methylstyene) [PS(OH)‐X] copolymers were synthesized and blends with 2,2,6,6‐tetramrthyl‐piperdine‐1‐oxyl end spin‐labeled PEO [SLPEO] were prepared. The miscibility behavior of all the blends was predicted by comparing the critical miscible polymer–polymer interaction parameter (χcrit) with the polymer–polymer interaction parameter (χ). The micro heterogeneity, chain motion, and hydrogen bonding interaction of the blends were investigated by the ESR spin label method. Two spectral components with different rates of motion were observed in the ESR composite spectra of all the blends, indicating the existence of microheterogeneity at the molecular level. According to the variations of ESR spectral parameters Ta, Td, ΔT, T50G and τc, with the increasing hydroxyl content in blends, it was shown that the extent of miscibility was progressively enhanced due to the controllable hydrogen bonding interaction between the hydroxyl in PS(OH) and the ether oxygen in PEO. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2312–2317, 2004
Microwave‐assisted synthesis of high‐molecular‐weight poly(ether imide)s by phase‐transfer catalysis
Authors: Gao Changlu , Zhang Suobo , Gao Lianxun , Ding Mengxian 
Published: April 2004

AbstractA facile and rapid polycondensation reaction of disodium bisphenol A with bis(chlorophthalimide)s was preformed with a domestic microwave oven in o‐dichlorobenzene by phase‐transfer catalysis. The polymerization reactions, in comparison with conventional heating polycondensation, proceeded rapidly and were completed within 25 min. The polymerizations gave the corresponding poly(ether imide)s with inherent viscosities of 0.55–0.92 dL g−1. The effects of various factors on the polymerization, such as the amount of the catalyst, the reaction time, and the microwave power were studied. The properties of the polymers were briefly characterized. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2415–2419, 2004
Kinetics of polymerization of dimer fatty acids with ethylenediamine
Authors: Heidarian Javad , Ghasem Nayef Mohd , Wan Daud Wan Mohd Ashri 
Published: April 2004

AbstractA generally applicable stoichiometric and kinetic model was developed for the polymerization of dimer fatty acids with ethylenediamine. The rate equations were second‐order before 90% conversion and were used between 405 and 475 K. The parameters of the rate equations were determined with nonlinear regression analysis. A comparison of the model predictions and the experimental data showed that the approach was useful in predicting the polymerization kinetics. The equilibrium constant changed from 3.175 to 7.311. The frequency factor and activation energy for the forward rate constant before 90% conversion were 2,716,894 kg mol−1 min−1 and 66.7 kJ mol−1, respectively. The equilibrium constant was independent of the temperature at frequency factor and activation energy values of 74.4 and 9.7 kJ mol−1, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2504–2513, 2004
Effect of poly(propylene carbonate) on the crystallization and melting behavior of poly(β‐hydroxybutyrate‐co‐β‐hydroxyvalerate)
Authors: Li J. , Lai M. F. , Liu J. J. 
Published: April 2004

AbstractThe crystallization and melting behavior of poly(β‐hydroxybutyrate‐co‐β‐hydroxyvalerate) (PHBV) and a 30/70 (w/w) PHBV/poly(propylene carbonate) (PPC) blend was investigated with differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR). The transesterification reaction between PHBV and PPC was detected in the melt‐blending process. The interaction between the two macromolecules was confirmed by means of FTIR analysis. During the crystallization process from the melt, the crystallization temperature of the PHBV/PPC blend decreased about 8°C, the melting temperature was depressed by 4°C, and the degree of crystallinity of PHBV in the blend decreased about 9.4%; this was calculated through a comparison of the DSC heating traces for the blend and pure PHBV. These results indicated that imperfect crystals of PHBV formed, crystallization was inhibited, and the crystallization ability of PHBV was weakened in the blend. The equilibrium melting temperatures of PHBV and the 30/70 PHBV/PPC blend isothermally crystallized were 187.1 and 179°C, respectively. The isothermal crystallization kinetics were also studied. The fold surface free energy of the developing crystals of PHBV isothermally crystallized from the melt decreased; however, a depression in the relative degree of crystallization, a reduction of the linear growth rate of the spherulites, and decreases in the equilibrium melting temperature and crystallization capability of PHBV were detected with the addition of PPC. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2514–2521, 2004
Frictional study of woven fabrics: The relationship between the friction and velocity of testing
Authors: Hermann D. , Ramkumar S. S. , Seshaiyer P. , Parameswaran S. 
Published: April 2004

AbstractA simple friction factor has been devised to characterize the frictional properties of textile materials. The friction factor enables universal comparisons among different textile materials. A poly(methyl methacrylate) sled has been used as a standard friction substrate to characterize the friction of a woven cotton fabric. The influence of the velocity of testing on the frictional characteristics has been studied in detail with the novel friction factor. This study elaborates the relationship between the speed of testing and the new fabric friction factor. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2420–2424, 2004
Mechanical and dynamical mechanical properties of chloroprene rubber and cellulose II composites
Authors: Martins Agnes F. , de Meneses Sergio M. , Visconte Leila L. Y. , Nunes Regina C. R. 
Published: April 2004

AbstractVulcanized composites of chloroprene rubber (CR) with cellulose II (Cel II) as a filler were investigated. Cel II, obtained by the coagulation of cellulose xanthate, was incorporated in the rubber by the traditional method. The filler content varied from 0 to 30 phr. For comparison purposes, carbon black (CB)–CR composites were also studied. The CB amount varied from 0 to 45 phr. The mechanical and dynamic mechanical properties were determined, and the CR composite containing 20 phr of Cel II showed the best set of properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2425–2430, 2004
Oxygen permeation resistance of polyethylene, polyethylene/ethylene vinyl alcohol copolymer, polyethylene/modified ethylene vinyl alcohol copolymer, and polyethylene/modified polyamide–ethylene vinyl alcohol copolymer bottles
Authors: Yeh Jen‐Taut , Huang Shyh‐Shiuan , Yao Wei‐Hua , Wang Ing‐Jing , Chen Cheng‐Chi 
Published: April 2004

AbstractThe oxygen permeation resistance of polyethylene (PE), polyethylene/ethylene vinyl alcohol copolymer (PE/EVOH), polyethylene/modified ethylene vinyl alcohol copolymer (PE/MEVOH), and polyethylene/modified polyamide–ethylene vinyl alcohol copolymer (PE/MPAEVOH) bottles was investigated. The oxygen permeation resistance improved significantly after the blending of ethylene vinyl alcohol copolymer (EVOH) barrier resins in PE matrices during blow molding; less demarcated EVOH laminas were found on the fracture surfaces of the PE/EVOH bottles. Surprisingly, the oxygen permeation resistance of the PE/MEVOH bottles decreased significantly, although more clearly defined modified ethylene vinyl alcohol copolymer (MEVOH) laminas were found for the PE/MEVOH bottles as the compatibilizer precursor contents present in the MEVOH resins increased. In contrast, after the blending of modified polyamide (MPA) in EVOH resins, more demarcated modified polyamide–ethylene vinyl alcohol copolymer (MPAEVOH) laminar structures were observed in the PE/MPAEVOH bottles as the MPA contents present in the MPAEVOH resins increased. In fact, with proper MPAEVOH compositions, the oxygen permeation resistance of the PE/MPAEVOH bottles was even better than that of the PE/EVOH bottles. These interesting oxygen barrier and morphological properties of the PE, PE/EVOH, PE/MEVOH, and PE/MPAEVOH bottles were investigated in terms of the free volumes, barrier properties, and molecular interactions in the amorphous‐phase structures of the barrier resins present in their corresponding bottles. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2528–2537, 2004
Compatibilization efficiency of styrene–butadiene triblock copolymers in polystyrene–polypropylene blends with varying compositions
Authors: Hlavatá D. , Hromádková J. , Fortelný I. , Hašová V. , Pulda J. 
Published: April 2004

AbstractThe compatibilization efficiency of two styrene‐butadiene‐styrene triblock copolymers with short (SB1) and long (SB2) styrene blocks was studied in polystyrene (PS)–polypropylene (PP) blends of composition 20, 50, and 80 wt % PS. The supramolecular structure of the blends was determined by small‐angle X‐ray scattering, and the morphology was studied with transmission electron microscopy and scanning electron microscopy. Structural changes in both the uncompatibilized and compatibilized blends were correlated with the values of tensile impact strength of these blends. Even though the compatibilization mechanisms were different in blends with SB1 and SB2, the addition of the block copolymers to the PS–PP 4/1 and PS–PP 1/4 blends led to similar structures and improved the mechanical properties in the same way. These block copolymers had a very slight effect on the impact strength in PS–PP 1/1 blends, exhibiting a nearly cocontinuous phase morphology. The strong migration of SB2 copolymers to the interface and of SB1 copolymers away from the interface were detected during the annealing of compatibilized PS–PP 4/1 blends. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2431–2441, 2004
Mechanical properties of polystyrene/polyamide 6 blends compatibilized with the ionomer poly(styrene‐co‐sodium acrylate)
Authors: Villarreal M. E. , Tapia M. , Nuño‐Donlucas S. M. , Puig J. E. , González‐Núñez R. 
Published: April 2004

AbstractThe compatibilizing effect of the ionomer, poly(styrene‐co‐sodium acrylate) (PSSAc), on immiscible blends of polystyrene (PS)/polyamide 6 (PA6) was studied by mechanical tests and scanning electron microscopy. The PSSAc acts as an effective compatibilizer because both the deformation at break (%) obtained by tensile stress–strain tests and the impact rupture energy are larger in blends containing small amounts of PSSAc. The morphologies of the fractured surfaces produced by tensile stress–strain tests of blends with or without the ionomer confirm that PSSAc increases the interfacial adhesion between PS and PA6 phases. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2545–2551, 2004
Synthesis and property of hydrogel membranes consisting of fumaramate with phosphorylcholine group
Authors: Oishi Tsutomu , Yamasaki Hirohito , Onimura Kenjiro , Fukushima Toshiyuki , Morihashi Seiji 
Published: April 2004

AbstractFumaramate bearing a phosphoryl choline group, isopropyl‐2‐[2′‐(trimethylammonium) ethyl phosphoryl] ethyl fumaramate (IPTPFA), was radically copolymerized with 2‐hydroxyethylmethacrylate (HEMA) in the presence of various crosslinking agents, water, and 2,2′‐azobis(isobutyronitrile) to obtain hydrogel membranes. The obtained hydrogel membranes adsorbed bovine serum albumin (BSA) much less than those of poly(HEMA), and the values of water content (H) were higher than those of poly(HEMA). The values of tensile strength and tensile elongation of the hydrogel were 68.4 g/mm2 and 239%, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2552–2557, 2004
Dependency of thermal and mechanical properties on the composition of mixed‐substituent poly(fluoroalkoxyphosphazenes)
Authors: Maher Andrew E. , Ambler Catherine M. , Powell Eric S. , Allcock Harry R. 
Published: April 2004

AbstractA series of poly(fluoroalkoxyphosphazenes) containing a mixture of 2,2,3,3,4,4,5,5‐octafluoropentoxy and 2,2,2‐trifluoroethoxy substituents was synthesized. The series included polymers with 25–94% incorporation of the trifluoroethoxy substituent, as well as single‐substituent polymers with 100% octafluoropentoxy or trifluoroethoxy side groups. Polymers were analyzed by multinuclear NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis, and were subjected to limiting oxygen index and microtensile testing. It was found that the Tg and Td values among the cosubstituted polymers varied little with changes in composition, but the mechanical properties varied over a wide range. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2569–2576, 2004