bluuebunny/crossref_metadata_2025_split huggingface dataset:
Grafting copolymerization of maleic anhydride onto styrene‐butadiene‐styrene block copolymer through solvothermal process
Authors: Qi Rongrong , Yu Qiuming , Shen Yanhan , Liu Qiaochu , Zhou Chixing 
Published: September 2006

AbstractThe grafting copolymerization of maleic anhydride (MAH) onto styrene‐butadiene‐styrene terpolymer (SBS) was carried out through a new synthesis method––solvothermal synthesis. Infrared (IR) spectra and solid state 13C‐NMR confirmed that maleic anhydride was successfully grafted onto the SBS backbone. The effects of different solvents, different initiators and their concentration, the amount of MAH, SBS concentration, and reaction time on the graft degree were evaluated, and the optimal conditions were obtained. Results indicated that the grafting reaction of MAH onto SBS through solvothermal method can be carried out in both good solvents and poor solvents, which are much different from the traditional solution grafting method, and high grafting degree can be obtained in good solvents. Finally, we also compared the grafting degree (GD) prepared by the solvothermal method with that by the melt grafting method and solution grafting method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5274–5279, 2006
Shrinkage and re‐expansion of extruded starch acetate foams
Authors: Zhou Jiahua , Hanna Milford 
Published: September 2006

AbstractThe effects of concentration of steam, heating time, pretreatment, and cooling conditions on the shrinkage and re‐expansion of extruded starch acetate foam were investigated. The re‐expansion ratio was determined from the degree by which the foam cells were moistened under the condition tested. The higher the concentration of steam used, the faster and greater the foam re‐expanded. Shrinkage was a result of the negative pressure resulting from cooling and condensation of steam or ethanol inside the foam and the unbalanced osmosis of steam transported out of the foam and air transported into the foam and the resistance of foam cell walls. Quenching re‐expanded foams led to significant shrinkage, especially for foams re‐expanded with highly concentrated steam. Shrinkage cannot be avoided even if the foam is kept at the same temperature it was expanded at the nozzle. Gradually reducing the degree of concentration of steam could reduce the shrinking tendency of the re‐expanded foam. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4264–4268, 2006
Thermal, morphological, and mechanical characteristics of polypropylene/polybutylene terephthalate blends with a liquid crystalline polymer or ionomer
Authors: Zhang Bao‐Yan , Sun Qiu‐Ju , Li Qian‐Yue , Wang Yang 
Published: September 2006

AbstractThermotropic side‐chain liquid crystalline polymer (SLCP) and corresponding side‐chain liquid crystalline ionomer (SLCI) containing sulfonate acid were used in the blends of polypropylene (PP) and polybutylene terephthalate (PBT) by melt‐mixing respectively, and thermal behavior, morphological, and mechanical properties of two series of blends were investigated by differential scanning calorimetry, Fourier transforms infrared spectroscopy (FTIR), scanning electron microscopy, and tensile measurement. Compared with the immiscible phase behavior of PP/PBT/SLCP blends, SLCI containing sulfonate acid groups act as a physical compatibilizer along the interface and compatibilize PP/PBT blends. FTIR analyses identify specific intermolecular interaction between sulfonate acid groups and PBT, and then result in stronger interfacial adhesion between these phases and much finer dispersion of minor PBT phase in PP matrix. The mechanical property of the blend containing 4.0 wt % SLCI was better than that of the other blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4712–4719, 2006
A comparative study of cardanol and aromatic oil as plasticizers for carbon‐black‐filled natural rubber
Authors: Alexander Mary , Thachil Eby Thomas 
Published: September 2006

AbstractCardanol is the main ingredient of cashew nut shell liquid, an agro‐byproduct. Its comparative merits vis‐a‐vis aromatic oil for plasticizing HAF‐black‐filled natural rubber (NR) is the subject of this article. Aromatic oil is the conventional plasticizer employed for such compounding requirements. The mechanical properties, ageing behavior, and torque time curves during cure of NR plasticized by both these materials are compared under identical conditions. It has been established that cardanol, when used as plasticizer, gives rise to similar tensile properties, shorter cure times, and superior ageing behavior compared to aromatic oil. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4835–4841, 2006
A comparative study on effects of two kinds of polymerization methods on grafting of polymer onto silica surface
Authors: Gao Baojiao , Wang Ruixin , Jiu Hongfang , Kong Delun 
Published: September 2006

AbstractIn this article we present the result of a comparative study of two kinds of polymerization methods—solution polymerization (sol. poly.) and dispersion polymerization (dis. poly.) for grafting polymer onto silica. As a model for the grafting polymerization reaction, styrene was chosen as the monomer and azo diisobutyronitrile (AIBN) as the initiator. The study aims at supplying theoretical reference for better selecting polymerization method to graft polymer on the silica particle surface. First, monolayers of 3‐methacryloylpropyl trimethoxysilane were chemically bonded onto the surfaces of micrometer‐sized silica gel particles, and so double bonds were immobilized onto the silica surface. Second, the copolymerizations between the immobilized double bonds and the monomer styrene were carried out, homopolymerizations of styrene followed, and finally polystyrene was grafted to the silica surfaces. Two kinds of polymerization methods, sol. poly. and dis. poly., were adopted respectively, and the effects of polymerization methods on grafting process were examined mainly. At the same time, the effects of different polymerization conditions on the grafting degree were researched. It was found that in the dis. poly. system the grafting degree is obviously higher than that in the sol. poly. system under the same polymerization conditions, and the grafting degree can go up to 47%, i.e. 47g/100g. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5808–5817, 2006
Photoinitiating behavior of bifunctional photoinitiator containing α‐hydroxyalkylphenone group on free‐radical polymerization
Authors: Ye Guodong , Yang Jianwen , Zhao Tianyi , Rao Rui , Zeng Zhaohua , Chen Yonglie 
Published: September 2006

AbstractPhotoinitiating behaviors of bis[4‐(2‐hydroxy‐isopropionyl)]ether photoinitiator on free‐radical polymerization have been investigated. The kinetics of photopolymerization initiated by the photoinitiator was studied by means of differential photocalorimetry. The bifunctional photoinitiator showed comparative performance with those commercial photoinitiators with monofunctional chromophoric group. The effect of UV intensity on the polymerization rate was investigated, and the value of exponential factor was found to be 0.5 at the beginning of polymerization, suggesting that the photopolymerization initiated by bis[4‐(2‐hydroxy‐isopropionyl)]ether followed biradical termination mechanism. Photosensitizer triethylamine improves the initiating efficiency while oxygen is shown to restrict polymerization in this system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5297–5302, 2006
Swelling of pH‐sensitive chitosan–poly(vinyl alcohol) hydrogels
Authors: Gunasekaran Sundaram , Wang Tao , Chai Chunxiang 
Published: September 2006

AbstractThe swelling properties of different chitosan–poly(vinyl alcohol) (PVA) hydrogels were investigated as functions of the medium pH and salt concentration. The maximum swelling ability of the hydrogels was at a buffer pH of approximately 3, regardless of the PVA content in the hydrogels. The maximum mass of the swollen hydrogels was about 13 times that of their contracted counterparts. The cyclical swelling and contraction between pH 3 and pH 7 buffers and pH 3 and pH 3 buffers with salt confirmed the Donnan swelling mechanism of these hydrogels. The swelling mechanism was considered the transfer of water molecules driven by a concentration gradient. This was represented by a simplified mass‐balance model, which neglected the effect of the ionization reaction, for the initial swelling period. The effective mass‐transfer coefficient of water molecules during swelling, estimated with this model, gradually decreased with increasing PVA content in the hydrogels. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4665–4671, 2006
Wood‐fiber‐reinforced poly(lactic acid) composites: Evaluation of the physicomechanical and morphological properties
Authors: Huda M. S. , Drzal L. T. , Misra M. , Mohanty A. K. 
Published: September 2006

AbstractThis article presents the results of a study of the processing and physicomechanical properties of environmentally friendly wood‐fiber‐reinforced poly(lactic acid) composites that were produced with a microcompounding molding system. Wood‐fiber‐reinforced polypropylene composites were also processed under similar conditions and were compared to wood‐fiber‐reinforced poly(lactic acid) composites. The mechanical, thermomechanical, and morphological properties of these composites were studied. In terms of the mechanical properties, the wood‐fiber‐reinforced poly(lactic acid) composites were comparable to conventional polypropylene‐based thermoplastic composites. The mechanical properties of the wood‐fiber‐reinforced poly(lactic acid) composites were significantly higher than those of the virgin resin. The flexural modulus (8.9 GPa) of the wood‐fiber‐reinforced poly(lactic acid) composite (30 wt % fiber) was comparable to that of traditional (i.e., wood‐fiber‐reinforced polypropylene) composites (3.4 GPa). The incorporation of the wood fibers into poly(lactic acid) resulted in a considerable increase in the storage modulus (stiffness) of the resin. The addition of the maleated polypropylene coupling agent improved the mechanical properties of the composites. Microstructure studies using scanning electron microscopy indicated significant interfacial bonding between the matrix and the wood fibers. The specific performance evidenced by the wood‐fiber‐reinforced poly(lactic acid) composites may hint at potential applications in, for example, the automotive and packaging industries. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4856–4869, 2006
Electrochromic properties and electrochromic device application of copolymer of N‐(4‐(3‐thienyl methylene)‐oxycarbonylphenyl)maleimide with thiophene
Authors: Ak Metin , Camurlu Pinar , Yılmaz Faruk , Cianga Luminita , Yağcı Yusuf , Toppare Levent 
Published: September 2006

AbstractA new copolymer of N‐(4‐(3‐thienyl methylene)‐oxycarbonylphenyl)maleimide (MBThi) with thiophene [P(MBThi‐co‐Th)] was synthesized electrochemically in the presence of tetrabutylammonium tetrafluoroborate as the supporting electrolyte, in acetonitrile/borontrifluoride ethylether solvent mixture (80 : 20, v/v). Spectroelectrochemical analysis of the resulting copolymer reflected electronic transitions at 440, 730, and ∼1000 nm, revealing π–π* transition, polaron, and bipolaron band formation, respectively. Switching ability was evaluated by a kinetic study via measuring the transmittance (%T) at the maximum contrast. Dual‐type polymer electrochromic devices (ECDs) based on P(MBThi‐co‐Th) and poly(ethylene dioxythiophene) (PEDOT) were constructed. Spectroelectrochemistry, switching ability, and stability of the devices were investigated by UV–vis spectroscopy and cyclic voltammetry. These devices exhibit low switching voltages (between 0.0 and +2.0 V) and short switching times with reasonable switching stability under atmospheric conditions. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 4500–4505, 2006
Preparation of microspheres with silicone oil cores and poly(N‐isopropylacrylamide) shells by physical coating
Authors: Xiao Xin‐Cai , Zhuo Ren‐Xi , Xu Jian , Liu Bing , Liu Ji‐Ying 
Published: September 2006

AbstractSurfactant‐free thermoresponsive microspheres with a silicone oil cores surrounded by poly(N‐isopropylacrylamide) shells have been successfully prepared by physical coating method for the first time. The influences of reaction temperature, N‐isopropylacrylamide (NIPAM) dosage, and stirring rate on the formation, morphology, particle size, and monodispersity of microspheres were experimentally studied. In the preparation of microspheres, when reaction temperature was above the lower critical solution temperature of poly(N‐isopropylacrylamide), products had higher yield of particles and narrower size distribution. With increasing NIPAM dosage, the particle diameter became larger and the shell layer thickened and the monodispersity became better. With increasing stirring rate, the particle diameter and the monodispersity decreased obviously. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5571–5576, 2006
Preparation and characterization of a hyperbranched polyethoxysiloxane based anti‐fouling coating
Authors: Wang Sheng‐Jie , Fan Xiao‐Dong , Si Qing‐Fa , Kong Jie , Liu Yu‐Yang , Qiao Wen‐Qiang , Zhang Guo‐Bin 
Published: September 2006

AbstractA hyperbranched polyethoxysiloxane was synthesized via hydrolytic polycondensation between methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS), with hydrochloride acid as catalyst. FTIR, 1H NMR, 29Si NMR, and GPC measurements confirmed that the polyethoxysiloxane synthesized was indeed a hyperbranched polymer with a degree of branching of 0.67. It was also found that there were no silanol groups in polymer matrix. This quality can effectively enhance its storage stability. Based on the hyperbranched polyethoxysiloxane, a novel antifouling coating with high curing speed at ambient temperature was developed. The recipe and other technique parameters of the coating were revealed and investigated. Experiments indicate that the coating performs well as an antifouling agent and can be applied to various ceramic products. By using scanning electron microscope (SEM) to inspect the surface of a polished tile applied with the coating, the antifouling mechanism was studied and the results were explained in accordance with the penetrating and crosslinking of the macromolecules of hyperbrached polyethoxysiloxane into the microdefects on the surface of tiles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5818–5824, 2006
Electrical behavior of PET films coated with nanostructured organic–inorganic hybrids
Authors: Saccani A. , Toselli M. , Messori M. , Fabbri P. , Pilati F. 
Published: September 2006

AbstractHybrid coatings, based on poly(ethylene oxide) (PEO) or polycaprolactone (PCL) and silica (SiO2), at different organic–inorganic compositions have been used to coat PET films employed in the electric industry to produce capacitors. The overall electrical behavior of the coated films has been investigated. The electrical strength of the coated films increases up to 10–15% of the uncoated ones regardless of polymer type (PEO/PCL) and amount of inorganic phase, as far as the thickness of the coating is below 5 μm. A systematic increase of surface electrical conductivity is found in all coated samples which however still behave as insulators. Permittivity and loss factor also increase particularly at low frequencies (< 10 Hz) on account of the presence of ions deriving from the sol–gel process and on the presence of interfacial polarization probably related to the coatings nanostructurated morphology which leads to phase separation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4870–4877, 2006
Synthesis of 3′,4′‐disubstituted terthiophenes. Characterization and electropolymerization. I. 3′,4′‐dibromo‐2,2′:5′,2″‐terthiophene in photovoltaic display
Authors: Vélez J. H. , Díaz F. R. , del Valle M. A. , Bernède J. C. , East G. A. 
Published: September 2006

AbstractRecent studies on conducting polymers have demonstrated that polymers of 3‐substituted thiophene produce very stable compounds. Although this kind of substitution improves the regularity, structural defects still exist. To overcome this drawback, the polymerization of 3,4‐disubstituted thiophene is proposed as a convenient way of synthesizing regular, highly conjugated conductive polymers. Our interest is thus focused on the synthesis of tetra‐substituted thiophene derivatives, their polymerization, electrochemical properties, spectral characteristics, oxidizing potential, and the feasibility of photocells development. In this article, we report the synthesis and characterization of 3′,4′‐dibromo‐2,2′:5′,2″‐terthiophene which, as such or modified, may be a good starting product for obtaining new monomers of 3′,4′‐disubstituted terthiophenes, that would allow the effect of the substituents on the properties of the respective polymers to be studied. In addition, the monomer was electropolymerized and the resulting deposit was electrochemically and morphologically characterized. Two conclusions were drawn: first, more uniform and homogeneous layers than those of polythiophene are obtained; second, the thin layers of the polymer, electron acceptors, absorb in the visible. Finally, photocells were assembled to investigate their photovoltaic effect. Although the so prepared solar cells showed some photovoltaic effect, the yield was low.© 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5314–5321, 2006
A novel flame retardant of spirocyclic pentaerythritol bisphosphorate for epoxy resins
Authors: Chen Gui‐Hong , Yang Bing , Wang Yu‐Zhong 
Published: September 2006

AbstractA novel flame retardant for epoxy resins, bisdiglycol spirocyclic pentaerythritol bisphosphorate (BDSPBP) was synthesized from the reaction of diglycol with spirocyclic pentaerythritol bisphosphorate diphosphoryl chloride, which was obtained from the reaction of phosphoryl chloride with pentaerythritol. Flammability of the cured epoxy resin systems consisted of diglycidyl ether of bisphenol A (DGEBA), low‐molecular‐weight polyamide and BDSPBP are investigated by vertical burning test (UL‐94) and limiting oxygen index test (LOI). The results indicate that BDSPBP has good flame retardance on epoxy. The thermogravimetric analysis (TGA) shows that the epoxy resin containing BDSPBP has a high yield of residual char at high temperatures, indicating that BDSPBP is an effective charring agent. From the SEM observations of the residues of the flame retardant systems burned, the compact charred layers can be seen, which form protective shields to protect effectively internal structure, and inhibit the transmission of heat and heat diffusion during contacting fire. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4978–4982, 2006
Nanocomposites from phenolic resin and various organo‐modified montmorillonites: Preparation and thermal stability
Authors: Jiang Wei , Chen Shinn‐Horng , Chen Yun 
Published: September 2006

AbstractPhenolic resin (PF)/montmorillonite (MMT) nanocomposites have been successfully prepared using intercalative polymerization of resole‐type phenolic resins in montmorillonites modified by octadecylamine (C18), benzyldimethylhexadecylammonium chloride (B2MH), benzyltriethylammonium chloride (B3E), and benzyldimethylphenylammonium chloride (B2MP). X‐ray diffraction measurements and transmission electron microscope observations showed that clay platelets were partially exfoliated or intercalated after complete curing of the phenolic resins. The cured nanocomposites were named as modifier‐MP (MP means montmorillonite‐phenolic resin), for example, B3E‐MP. Thermogravimetric analysis showed that thermal decomposition temperatures (Tds) of the cured nanocomposites B2MP‐MP (826 K), B3E‐MP (794 K), and B2MH‐MP (783 K) were much higher than those of C18‐MP (768 K) and cured phenolic resin (737 K). Therefore, thermal stability of the nanocomposites depends mainly on the chemical structure of the organic modifiers. B2MP‐MP possesses the highest Td since B2MP contains both benzyl and phenyl groups, followed with B3E‐MP and B2MH‐MP whose modifiers contain only one benzyl group. This is attributable to favorable interaction between phenolic resin and organic modifiers containing benzene rings. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5336–5343, 2006
Preparation and photophysical properties of organic fluorescent polymers and their nanoparticles
Authors: Uthirakumar Periyayya , Hong Chang‐Hee , Suh Eun‐Kyung , Lee Youn‐Sik 
Published: September 2006

AbstractNew classes of stable organic florescent polymer nanoparticles were prepared from the corresponding tetrahydrofuran (THF) solutions, upon slow evaporation of solvent under a mild vacuum. Uniform spherical nanospheres having mean diameter of ˜ 500–700 nm, showed enhanced fluorescence emission in solution, but it diminished when it is destroyed using an organic base. These end‐capped fluorescent polymers are highly stabilized in the excited states at higher concentration in solution, leads no more intra‐ and intermolecular interactions among the excited molecules, because of the absence of free functional groups. The significant enhancement in fluorescence emission was attributed to the high level of molecular stacking in the fluorescent nanoparticles, when compared with micron‐sized isolated powder sample. In addition, these fluorescent polymers exhibited significant thermal properties, along with better solubility in most of common organic solvents for their future application. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5344–5350, 2006
Structural investigations of (9‐ethyl‐carbazol‐6‐yl) methyl methacrylate/methyl acrylate copolymers using two‐dimensional NMR spectroscopy
Authors: Brar Ajaib Singh , Gandhi Sonia 
Published: September 2006

Abstract(9‐Ethyl‐carbazol‐6‐yl) methyl methacrylate/methyl acrylate (E/A) copolymers of different compositions were prepared by solution polymerization by varying the molar infeed ratio, using AIBN as initiator at 60°C. The reactivity ratios calculated by Kelen–Tudos (KT) method were found to be rE = 1.16 ± 0.02 and rA = 0.69 ± 0.01 whereas those calculated from RREVM method were found to be rE = 1.18 and rA = 0.68. The molecular weights (Mw) and polydispersity index (PDI, Mw/Mn) were determined using gel permeation chromatography (GPC). Glass transition temperatures (Tg) for different compositions of E/A copolymers were determined using differential scanning calorimetry (DSC). Copolymer molar outfeed ratio (FE) was calculated from 1H NMR spectra. The α‐methyl, methine, backbone methylene, and quaternary carbon resonance signals of the copolymers were distinguished using 13C{1H}, DEPT‐45, ‐90, and ‐135 NMR techniques. The α‐methyl and β‐methylene showed compositional and configurational sensitivity up to pentad and tetrad level, respectively, whereas methine showed only compositional sensitivity up to pentad level. Unambiguous assignments for 1H and 13C{1H} NMR spectra were done by correlating 1D (1H, 13C{1H}, DEPT) and 2D (HSQC, TOCSY) NMR data. The spectral assignments for carbonyl region were done by studying higher bond order couplings by heteronuclear multibond correlation (HMBC) spectra. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5595–5606, 2006
Properties and morphology of poly(L‐lactide)/clay composites according to the clay modification
Authors: Hun Shim Jae , Soo Kim Eung , Hiuk Joo Jung , Yoon Jin San 
Published: September 2006

AbstractMontmorillonite (MMT) was modified with dodecylamine, 1,12‐diaminododecane, and 1,11‐aminoundecanoic acid to prepare CHMMT, NHMMT, and COMMT, respectively. The three clays were mixed with poly(L‐lactide) (PLLA) with the aid of chloroform. Depending on the modifiers, PLLA/MMT composites exhibited different mechanical properties and morphology. A completely exfoliated morphology was observed in the PLLA/COMMT composite (PLACO). The PLACO exhibited the best tensile properties among the tested composites because of the finest dispersion of the clay layers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:4983–4988, 2006