bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and characterization of hydrocarbon polyol polyurethane and silicone magnetorheological polymeric gels
Authors: Fuchs Alan , Xin Mei , Gordaninejad Faramarz , Wang Xiaojie , Hitchcock Gregory H. , Gecol Hatice , Evrensel Cahit , Korol George 
Published: February 2004

AbstractMagnetorheological polymeric gels (MRPG) have been developed for use in semi‐active magnetorheological fluid (MRF) dampers and other magnetorheological (MR) devices. The novel MRPGs are prepared by suspending iron particles in polymeric gels. Off‐state (i.e, no applied magnetic field) viscosity and settling behavior can be controlled through the selection of polymeric gels. In this study, tunable rheological properties were investigated with a piston‐driven flow type rheometer with a shear rate varying from 20 s−1to 6,000 s−1. Silicone MRPG (with 84.5 wt % iron particles) has controllable viscosity and a high shear yield stress over a wide range of shear rates. Silicone MRPG (79.5 wt % iron particles) has the lowest viscosity of those studied. Polyurethane MRPG has the lowest settling rate. The order of addition of magnetic particles and polymer during the polymerization process affects the MRPG final off‐state apparent viscosity (80% increase in apparent viscosity for silicone MRPG polymerized after adding iron particles). This indicates that polymer gels modify the surface properties of the magnetic particles, causing interaction among particles. The dynamic shear yield stress is higher for fluids with better dispersion stability. Polyurethane MRPG, which has the lowest settling rate, has a high dynamic yield stress (23 kPa at 350 mT). Both dynamic and static shear stress values of the MRPGs were found to be similar in magnitude (5–8 kPa at 120 mT for silicone MRPG with 84.5 wt % iron particles and polyurethane MRPG), indicating that MRPGs can provide consistent performance in devices. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1176–1182, 2004
Preparation and properties of (BATB–ODPA) polyimide–clay nanocomposite materials
Authors: Yeh Jui‐Ming , Chen Chi‐Lun , Kuo Tai‐Hung , Su Wen‐Fen , Huang Hsi‐Ya , Liaw Der‐Jang , Lu Hsin‐Yi , Liu Chi‐Fong , Yu Yuan‐Hsiang 
Published: February 2004

AbstractA series of polymer–clay nanocomposite (PCN) materials consisting of 1,4‐bis(4‐aminophenoxy)‐2‐tert‐butylbenzene–4,4′‐oxydiphthalic anhydride (BATB–ODPA) polyimide (PI) and layered montmorillonite (MMT) clay were successfully prepared by an in situ polymerization reaction through thermal imidization up to 300°C. The synthesized PCN materials were subsequently characterized by Fourier‐Transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of material composition on thermal stability, mechanical strength, molecular permeability and optical clarity of bulk PI and PCN materials in the form of membranes were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), molecular permeability analysis (GPA) and ultraviolet‐visible (UV/VIS) transmission spectra, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1072–1079, 2004
Novel aliphatic polyketone fiber by a wet‐spinning method using aqueous composite metal salt solutions
Authors: Morita Toru , Taniguchi Ryu , Matsuo Teruhiko , Kato Jinichiro 
Published: February 2004

AbstractPoly(1‐oxotrimethylene), obtained by the perfectly alternating polymerization of ethylene and carbon monoxide, was successfully dissolved in composite metal salt solutions such as zinc chloride and calcium chloride aqueous solutions. Certain poly(1‐oxotrimethylene) solutions exhibited a phase‐separation point of 0°C or greater; the different phase‐separation temperatures depended on the metal salt composition ratio, the polymer molecular weight, and the polymer concentration. When a solution with a phase‐separation point was used for wet spinning, a coagulation temperature below the phase‐separation point resulted in gelation of the filament, which was caused by a temperature jump during the coagulation process; this yielded a coagulated filament with a dense and homogeneous cross‐sectional structure. The hot drawing of the coagulated fiber produced a high‐performance polyketone fiber with high strength and high elastic modulus [tenacity = 18.5 cN/dtex (2.4 GPa); elongation = 5%; elastic modulus = 450 cN/dtex (59 GPa)].With a solution that exhibited no phase‐separation temperature, coagulation proceeded as the coagulant penetrated from the fiber surface into the filament inside, yielding a coagulated filament with a skin–core structure. The maximum tenacity achieved with this skin–core coagulated filament was as low as 15 cN/dtex (1.9 GPa). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1183–1189, 2004
Studies on Indian silk. I. Macrocharacterization and analysis of amino acid composition
Authors: Sen Kushal , Babu K Murugesh 
Published: February 2004

AbstractThis first in a series of articles characterized the different varieties of Indian silk for their macrostructural parameters, such as filament length, degumming loss, denier, cross section, moisture regain, and intrinsic viscosity, for example. The results of amino acid analysis using a reverse‐phase technique were also reported. Five Indian silk varieties—two mulberry (bivoltine and crossbreed) and three nonmulberry (tasar, muga, and eri)—were investigated. The differences existing between the different varieties and the extent of lengthwise variations within a cocoon in the dimensional and macrostructural parameters were discussed. It was observed that denier of the filament decreases considerably from the outer to the inner layers, whereas density showed an increasing trend in all the varieties. Both the mulberry silks demonstrated lower moisture regain. Electron micrographs of all the nonmulberry varieties showed microvoids in their cross section. Fraction studies showed the development of mushroom structure on the tips. In both types of mulberry silk, glycine, alanine, and serine constitute about 82% of the amino acids present. On the other hand, in nonmulberry silks, these constitute about 73% with a high proportion of alanine. The nonmulberry varieties showed a substantial proportion of amino acids with bulky side groups. Similarly, the higher hydrophilic to hydrophobic amino acid ratio (9.06–9.85) for nonmulberry silks, compared against that of the mulberry varieties (5.29–6.22), was shown to be responsible for the higher moisture content of nonmulberry silks. Cystine and methionine were present in all the varieties. The higher intrinsic viscosity of nonmulberry varieties suggested their higher molecular weight. Through amino acid analysis, it was shown that there is no difference in chemical architecture between the outer and the inner layers of cocoons. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1080–1097, 2004
Studies on Indian silk. III. Effect of structure on dyeing behavior
Authors: Sen Kushal , Babu K Murugesh 
Published: February 2004

AbstractThis third in a series of articles deals with the analysis of the dyeing behavior of two mulberry and three nonmulberry varieties of silk. The results of the dyeing tests carried out were discussed in relation to the physical and chemical structure of the silk fibers. Noticeable differences in the dye uptake were observed among the different varieties of silk. Mulberry varieties showed higher dye uptake compared to that of all three nonmulberry varieties. Among the nonmulberry varieties, tasar shows higher dye uptake followed by eri and muga. Interestingly, dye uptake reduces significantly within a variety from the outer to the inner layers. The reduction within a variety was found to correlate well with the morphological parameters. Determination of morphology of fibers confirmed significant differences in structural parameters such as crystallinity, orientation, density, and birefringence, for example, between and within varieties. An increase in all these parameters was observed as one moves from the outer to the inner layers within a variety. The differences in the dye uptake of different varieties of silk correlated well with the physical as well as chemical structure of silk fibers. Dye uptake differences between the varieties were found to correlate with the end amino groups. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1116–1123, 2004
Effects of acrylic‐based processing aids on processibility, rheology, thermal and structural stability, and mechanical properties of PVC/wood–sawdust composites
Authors: Sombatsompop N. , Phromchirasuk C. 
Published: February 2004

AbstractMethyl methacrylate and ethylacrylate (MMA‐co‐EA) and methyl methacrylate and butylacrylate (MMA‐co‐BA) copolymeric processing aids were introduced into poly(vinyl chloride) (PVC)/33.3 wt % wood–sawdust composites containing 0.6 and 2.4 phr of calcium stearate lubricant. The properties of the composites were monitored in terms of processibility, rheology, thermal and structural stability, and mechanical properties. It was found that the mixing torque, wall shear stress, and extrudate swell ratio increased with increasing processing aid content because of increased PVC entanglement. MMA‐co‐BA (PA20) was found to be more effective than MMA‐co‐EA (K120 and K130), this being associated with the flexibility of the processing aids, and the dipole–dipole interactions between sawdust particles and polymeric processing aids. The sharkskin characteristic of the composite extrudate at high extrusion rate was moderated by the presence of processing aids. Adding the acrylic‐based processing aids and lubricant into PVC/sawdust composites improved the thermal and structural stability of the composites, which were evidenced by an increase in glass transition and decomposition temperatures and a decrease in polyene sequences, respectively. The changes in the mechanical properties of the composites involved a composite homogeneity, which was varied by degree of entanglement and the presence of wood sawdust, and un‐reacted processing aids left in the composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 782–790, 2004
Synthesis and tensile properties of a novel composite of Chlorella and polyethylene
Authors: Otsuki Toshi , Zhang Farao , Kabeya Hiroshi , Hirotsu Takahiro 
Published: February 2004

AbstractA novel composite of the green microalga Chlorella sp. with polyethylene (PE) was synthesized through chemical modification of PE with maleic anhydride (MA), with respect to the biological fixation of CO2 with Chlorella sp. The interaction of Chlorella grains with a PE matrix is strikingly enhanced by the chemical modification of PE with MA. The tensile strength of a Chlorella–MA‐modified PE composite (Ch–MPE) with a Chlorella content of 40 wt % is more than 2 times greater than that of a composite derived from unmodified PE. The marked increase in tensile strength is attributed to the formation of chemical bonds between Chlorella grains and the PE matrix, from IR and SEM studies. Because of the satisfactory thermal plasticity of Ch–MPE, it can be easily shaped into plate and dishlike moldings by a heat‐pressurizing method. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 812–816, 2004
Studies on castor oil–based polyurethane/polyacrylonitrile interpenetrating polymer network for toughening of unsaturated polyester resin
Authors: Guhanathan S. , Hariharan R. , Sarojadevi M. 
Published: February 2004

AbstractTricomponent interpenetrating polymer network (IPN) systems involving castor oil, toluenediisocyanate (TDI), acrylonitrile (AN), ethylene glycol diacrylate (EGDA), and general‐purpose unsaturated polyester resin (GPR) were prepared with various compositions. The structures of the IPNs at various stages were confirmed using FTIR. The thermal stability of the IPNs was studied using TGA, which indicated that the polyurethane/polyacrylonitrile/GPR (PU/PAN/GPR) IPN underwent single‐stage decomposition, showing perfect compatibility at the IPN composition of 10 : 90 (PU/PAN : GPR). The mechanical properties such as tensile, flexural, impact, and hardness for the IPNs with various compositions were determined. It was found that the tensile strength of the GPR matrix was decreased and flexural and impact strengths were increased upon incorporating PU/PAN networks. The swelling properties in water and toluene were also studied. The morphology of the IPNs was studied using SEM. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 817–829, 2004
Reactive blends of epoxy resin (DGEBA) crosslinked by anionically polymerized polycaprolactam: Process of epoxy cure and kinetics of decomposition
Authors: Gupta Alka , Singhal Reena , Nagpal A. K. 
Published: February 2004

AbstractThe curing reactions, kinetics, morphology, and thermal stability of the reactive blends of diglycidyl ether of bisphenol‐A (DGEBA) and polycaprolactam were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis. DSC studies showed that the heat of reaction (ΔH) increased when the DGEBA content was increased from 50 to 80 wt % and increased drastically above 70 wt % DGEBA content because of an increase in the extent of crosslinking. The activation energy and pre‐exponential factor of cure reactions increased drastically with an increase in the DGEBA content above 70 wt % because of a drastic increase in crosslink density. The extent of curing reaction of polycaprolactam with DGEBA is dependent on the blend composition. The nucleophilic attack on oxirane ring by amide nitrogen of polycaprolactam is a dominant curing reaction in low DGEBA compositions, and another type of curing reaction with relatively large activation energy and pre‐exponential factor also occurred, which becomes dominant when the DGEBA content reaches above 70 wt %. FTIR studies also revealed that two types of reactions do exist during the curing of polycaprolactam with DGEBA. It was observed during SEM studies that the reactive blends show multiphase system and on increasing the DGEBA content from 50 to 80 wt %, the mixing of the two phases increased. The reactive blend Ep80Ca20 with 80 wt % DGEBA content exhibits a single‐phase system because of better mixing of the two phases. The results of thermogravimetric analysis also indicate that the initial degradation temperature (Ti), activation energy (E), and pre‐exponential factor (Z) increased with increasing DGEBA content from 50 to 80 wt % in the reactive blends and increased drastically above 70 wt % DGEBA content due to the higher crosslink density. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 687–697, 2004
Synthesis and characterization of functional copolymer of Linalool and vinyl acetate: A kinetic study
Authors: Shukla Anjali , Srivastava A. K. 
Published: February 2004

AbstractLinalool (LIN) and vinyl acetate (VA) were copolymerized by benzoyl peroxide (BPO) in p‐xylene at 60°C for 90 min. The system follows nonideal kinetics: Rpα[I]0.6[LIN]1.2[VA]1.1. It results in the formation of alternating copolymer as evidenced from reactivity ratios as r1 (VA) = 0.01, r2 (LIN) = 0.0015, which have been calculated by Kelen–Tudos method. The overall activation energy is 82 kJ/mol. The FTIR spectrum of the copolymer shows the presence of the band at 3425 cm−1 due to alcoholic group of LIN and at 1641 cm−1 due to >CO group of VA. The 1H‐NMR spectrum shows peaks at 7.0–7.7 δ due to hydroxy proton of LIN and at 1.0–1.4 δ due to acetoxy protons of VA. 13C‐NMR spectrum of copolymer shows peaks at 167 ppm due to acetoxy group and at 75–77 ppm due to COH group. The Alfrey–Price Q–e parameters for LIN has been calculated as Q2 = 1.24 and e2 = 3.11. The copolymer is highly thermally stable and has a glass transition temperature (Tg) of 85°C, evaluated from DSC studies. The mechanism of copolymerization has been elucidated. This article also reports measurement of Mark–Houwink constants in THF at 25°C by means of GPC as α = 0.8 and K = 3.0 × 10−4 dl/g. The thermal decompositions of copolymer are established with the help of TGA technique. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1134–1143, 2004
Synthesis of resol–layered silicate nanocomposites by reaction exfoliation with acid‐modified montmorillonite
Authors: Wang Hongsheng , Zhao Tong , Yan Yehai , Yu Yunzhao 
Published: February 2004

AbstractResol–layered silicate nanocomposites were prepared by the intercalative polymerization of phenol and formaldehyde in the presence of acid‐modified montmorillonite (HMMT). The nanocomposites were studied by means of X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, dynamic mechanical analysis (DMA), and rheological measurements. The exfoliation of HMMT was promoted by the intragallery reactions catalyzed by protons in the galleries of the clay, whereas the extragallery polymerization catalyzed by ammonia went on simultaneously. The nanocomposites showed higher glass‐transition temperatures in the DMA diagram compared with the resol counterparts. The impact strength was improved significantly by the incorporation of the clay. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 791–797, 2004
Synthesis and characterization of epoxidized styrene–butadiene rubber/silicon dioxide hybrid materials
Authors: de Luca Maria Augusta , Machado Taís Espíndola , Notti Renan Beretta , Jacobi Marly Maldaner 
Published: February 2004

AbstractHybrid materials were synthesized from epoxidized (68, 43, or 14%) styrene–butadiene rubber (SBR) and the hydrolysis product of tetraethoxysilane (TEOS) in situ under ultrasonic irradiation. The products were characterized with thermal analysis (differential scanning calorimetry and thermogravimetric analysis), stress–strain tests, scanning electron microscopy (including energy‐dispersive spectrometry), and swelling in tetrahydrofuran and water. The most transparent were those prepared from SBR with the highest degree of epoxidation, whereas those obtained from less epoxidized SBR and with larger amounts of TEOS showed distinct phases that could be considered two hybrid phases (one rich in TEOS and another rich in SBR). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 798–803, 2004
Preparation and properties of styrene–butadiene rubber based nanocomposites: The influence of the structural and processing parameters
Authors: Sadhu Susmita , Bhowmick Anil K. 
Published: February 2004

AbstractRubber‐based nanocomposites were prepared with octadecyl amine modified sodium montmorillonite clay and styrene–butadiene rubber with different styrene contents (15, 23, and 40%). The solvent used to prepare the nanocomposites, the cure conditions, and the cure system were also varied to determine their effect on the properties of the nanocomposites. All the composites were characterized with X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The XRD studies revealed exfoliation for the modified clay–rubber composites. The TEM photomicrographs showed a uniform distribution of the modified clay in the rubber matrix. The thickness of the particles in the exfoliated composites was around 10–15 nm. Although the FTIR study of the unmodified and modified clays showed extra peaks due to the intercalation of the amine chains into the gallery, the spectra for the rubber–clay nanocomposites were almost the same because of the presence of a very small amount of clay in the rubber matrix. All the modified clay–rubber nanocomposites displayed improved mechanical strength. The styrene content of the rubber had a pronounced effect on the properties of the nanocomposites. With increasing styrene content, the improvement in the properties was greater. Dicumyl peroxide and sulfur cure systems displayed similar strength, but higher elongation and slightly lower modulus values were obtained with the sulfur cure system. The curing of the samples at four different durations at 160°C showed that the cure time affected the properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 698–709, 2004
Synthesis and coating characteristics of novel calcium‐containing poly(urethane ethers)
Authors: Jayakumar R. , Lee Y.‐S. , Nanjundan S. 
Published: February 2004

AbstractCalcium salt of mono(hydroxypentyl)phthalate [Ca(HPP)2] was synthesized by the reaction of 1,5‐pentanediol, phthalic anhydride, and calcium acetate. Calcium‐containing poly(urethane ethers) (PUEs) were synthesized by the reaction of hexamethylene diisocyanate (HMDI) or toluylene 2,4‐diisocyanate (TDI) with a mixture of Ca(HPP)2 and poly(ethylene glycol) (PEG300 or PEG400) with di‐n‐butyltin dilaurate as a catalyst. We synthesized a series of calcium‐containing PUEs with different compositions by taking the molar ratio of Ca(HPP)2 : PEG300 or PEG400 : diisocyanate (HMDI or TDI) as 2 : 2 : 4, 3 : 1 : 4, and 1 : 3 : 4 to study the coating properties of the PUEs. Blank PUEs without a calcium‐containing ionic diol were also prepared by the reaction of PEG300 or PEG400 with HMDI or TDI. The PUEs were well characterized by fourier transform infrared spectroscopy, 1HNMR, −13C‐NMR, solid‐state cross‐polarity/magic‐angle spinning 13C‐NMR, viscosity, solubility, and X‐ray diffraction studies. The thermal properties of the polymers were also studied with thermogravimetric analysis and differential scanning calorimetry. The PUEs were applied as a top coat on acrylic‐coated leather, and their physicomechanical properties were also studied. The coating properties of PUEs, including tensile strength, elongation at break, tear strength, water vapor permeability, flexing endurance, cold crack resistance, abrasion resistance, color fastness, and adhesive strength, were better than the standard values. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 710–721, 2004
A novel method for the preparation of monocarboxyl‐end‐grouped polycaprolactam with an adjustable molecular weight
Authors: Zhang Yi , Zhang Quanling , Cheng Kailiang , Xu Jiarui 
Published: February 2004

AbstractA novel method was used to synthesize adjustable‐molecular‐weight polycaprolactams with monocarboxyl end groups. The reaction device and conditions are discussed. The products were characterized by Fourier transform infrared spectroscopy, 1H‐NMR spectroscopy, high‐resolution pyrolysis gas chromatography–mass spectrometry, and wide‐angle X‐ray diffraction. The thermal properties were studied by differential scanning calorimetry and thermogravimetric analysis. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 722–727, 2004
Adsorption of Cu(II) ions from an aqueous solution by crosslinked amphoteric starch
Authors: Xu Shi‐Mei , Feng Shun , Yue Fan , Wang Ji‐De 
Published: February 2004

AbstractThe adsorption process of Cu(II) ions from aqueous solutions by crosslinked amphoteric starch with quaternary ammonium and carboxymethyl groups was investigated. The adsorption capacity was found to be dependent on the solution pH, the dose of the crosslinked amphoteric starch, and the initial concentration of Cu(II) ions. Moreover, the adsorption capacity increased with an increasing degree of substitution (DS) of the carboxymethyl groups. The adsorption followed a Freundlich adsorption isotherm. The adsorption process was endothermic, and the thermodynamic parameters were calculated at different DS values. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 728–732, 2004