bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and characterization of syndiotactic polystyrene/ethylene‐propylene copolymer blends
Authors: Choi Won‐Mook , Park Cheon‐Il , Park O Ok , Lim Jae‐Gon 
Published: October 2002

AbstractThe reactive compatibilization of syndiotactic polystyrene (sPS)/oxazoline‐styrene copolymer (RPS)/maleic anhydride grafted ethylene‐propylene copolymer (EPR‐MA) blends is investigated in this study. First, the miscibility of sPS/RPS blends is examined by thermal analysis. The cold crystallization peak (Tcc) moved toward higher temperature with increased PRS, and, concerning enthalpy relaxation behaviors, only a single enthalpy relation peak was found in all aged samples. These results indicate that the sPS/RPS blend is miscible along the various compositions and RPS can be used in the reactive compatibilization of sPS/RPS/EPR‐MA blends. The reactive compatibilized sPS/RPS/EPR‐MA blends showed finer morphology than sPS/EPR‐MA physical blends and higher storage modulus (G') and complex viscosity (η*) when RPS contents were increased. Moreover, the impact strength of sPS/RPS/EPR‐MA increased significantly compared to sPS/EPR‐MA blend, and SEM micrographs after impact testing show that the sPS/RPS/EPR‐MA blend has better adhesion between the sPS matrix and the dispersed EPR‐MA phase. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2084–2091, 2002
Research of a membrane's material by reversed gas chromatography
Authors: Romaniuk O. I. , Turovskiy A. A. , Kurechko N. I. , Prystansky R. E. , Zaikov G. E. , Zaikov V. G. 
Published: October 2002

AbstractResearch of a membrane's polymeric material obtained by photoinitiated radical polymerization of oligocarbonate methacrylate and butyl methacrylate (BMA) was conducted by the method of reversed gas chromatography. The presence of defects of two types in the polymer was confirmed: as gaps between grains, and spongy interlayers. It has been established, that the relative size of gaps between grains more than in 1.5 times exceeds the size of interlayers between grains. The selective separation of substances proceeds through interlayers between grains. The size of interlayers (polymer's Tg) depends on structure of an initial composition. Increase of the BMA contents in an initial composition leads to polymer's Tg increase, condensation of interlayers between grains, and increase of selectivity of the appropriate membrane. This dependence has an extremal character. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2725–2728, 2002
Molecular structure and hydrophobicity of polymeric fluorocarbon films deposited on PET substrates
Authors: Qi H. J. , Wang D. , Ma Z. L. , Sun S. Q. , Sui Q. Y. , Zhang W. P. , Lu J. J. 
Published: October 2002

AbstractSputter‐coated polymeric fluorocarbon films (PFCF) on poly(ethylene terephthalate) (PET) are prepared under conditions of various power and pressure levels. By analysis of X‐ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR), low fluorine‐to‐carbon (F/C) ratios, 1.02–0.61, indicate that the deposited films are highly crosslinked‐unsaturated and the F/C ratio is found to be remarkably influenced by the power and slightly affected by the pressure due to the change in various structure components in the film molecules. The nonwettable properties of the PFCF are consistent with the results obtained by XPS‐IR analysis. The cleavage of the sharp peak assigned to CO stretch in the FTIR spectra of the PFCF‐PET film can be thought to be an evidence related to the newly formed FC bond on a certain site of ester group next to benzene ring in PET macromolecules. Therefore, the chemical bond at the interface between FCPF and PET can be expected to enhance the joint strength of the interface. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1843–1850, 2002
Synthesis and properties of photochromic cholesteric liquid crystalline polysiloxane containing chiral mesogens and azobenzene photochromic groups
Authors: Zhi Junge , Zhang Baoyan , Zang Baoling , Shi Guohua 
Published: October 2002

AbstractA series of novel thermotropic side‐chain liquid crystalline polymers(P0–P12) were synthesized by grafting copolymerization of mesogenic monomer cholesteryl undecylenate (M1) and photochromic monomer 4‐allyoxy‐4′‐nitroazobenzene (M2) on polymethylhydrosiloxane. The chemical structures of polymers were characterized by infrared (IR) and ultraviolet (UV) spectroscopy. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to measure the thermal properties of those polymers, and the mesogenic properties were characterized by polarized optical micrograph, DSC, wide‐angle X‐ray diffraction and small‐angle X‐ray scattering. The glass transition temperatures (Tgs) of the polymers increased from P0 to P4 and decreased from P5 to P12. The clearing point temperatures (Tis) of the polymers P1–P12 were lower than that of P0, but increased from P1 to P4 and decreased from P5 to P12. They showed thermotropic liquid crystalline properties in a broad mesogenic region at temperatures >100°C. The polymers P0–P8 exhibited a cholesteric mesophase with oily streaks and lined texture, and polymers P9–P12 showed a chiral smectic mesogenic phase with a layered texture. All of the polymers were thermally stable to ∼ 320°C. The UV‐induced trans–cis photoisomerization was investigated for the azo monomer and polymers P8 and P12. The solution of the azo monomer and liquid crystalline polymers P8 and P12 can undergo photoisomerization, and the environments of the azo group were responsible for the aforementioned photochemical process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2155–2162, 2002
Activity of a β‐nucleating agent for isotactic polypropylene and its influence on polymorphic transitions
Authors: Marco C. , Gómez M. A. , Ellis G. , Arribas J. M. 
Published: October 2002

AbstractThe influence of a nonpigmenting β‐nucleating additive in the crystallization of isotactic polypropylene (iPP) is investigated by differential scanning calorimetry and X‐ray diffraction. It is found that this additive induces the formation of a very high level of the trigonal modification of iPP. The crystallization and melting behavior of the nucleated systems are studied as a function of the cooling and heating rates and the control of the final temperature during the cooling process. The nucleating agent exerts an important effect on the crystallization temperatures and the polymorphic transitions of iPP, delaying the β–α recrystallization process through an increase in the stability of the trigonal crystals. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 531–539, 2002
Mechanical and dynamic mechanical properties of jute fibers–Novolac–epoxy composite laminates
Authors: Datta Chandan , Basu Diya , Banerjee Amarnath 
Published: October 2002

AbstractA study was done of jute composite using a polymer matrix of epoxidized Novolac resin (ENR), diglycidyl ether of bisphenol A (DGEBA)–based epoxy, and their blends with different weight percentages of the resins. It was found that on blending ENR with DGEBA, the storage modulii at room temperature are enhanced by about 100% or more in the case of 30 and 40% ENR‐containing matrices, whereas the enhancement in the case of 20 and 12% ENR‐containing matrices is only 50% that of the pure matrix. It was also observed that the tan δ peak heights of the composites containing 30 and 40% ENR are closer to that of 20% ENR‐containing composite. The probable explanation drawn on the basis of experimental findings of DMA and mechanical analysis is that by blending ENR with DGEBA epoxy it is possible to manufacture jute composites with increased stiffness without sacrificing their ductility. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2800–2807, 2002
Flow‐injection polymer analysis of styrenic block copolymers. II
Authors: Poché Drew S. , Esneault Calvin P. , Roetker Susan L. , Heitman Tim E. 
Published: October 2002

AbstractA flow‐injection polymer analysis (FIPA) method for the dilute solution characterization of unsaturated styrenic block copolymers was developed. The method is rapid, works with both butadiene and isoprene comonomers, and covers a range of 0–100% styrene content in the polymer. Solutions of the polymer were introduced into a flowing mobile phase and monitored by an array of three close‐coupled detectors: a right‐angle laser light‐scattering unit, a differential refractive index detector (DRI), and a differential pressure viscometer. In addition, a separate, dual‐detector instrument was set up specifically to evaluate the styrene content by the FIPA method. In that case, the detectors were a DRI and an ultraviolet detector. Within an analysis time of a few minutes, information on molecular weight, molecular size, and comonomer composition could be obtained directly. The data were compared to those obtained from a preexisting gel permeation chromatography analysis method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2190–2201, 2002
Photochemically induced birefringence in polyurethanes containing donor‐acceptor azobenzenes as photoresponsive moieties
Authors: Hasegawa Makoto , Ikawa Taiji , Tsuchimori Masaaki , Watanabe Osamu 
Published: October 2002

AbstractThree kinds of photoresponsive polyurethanes containing slightly different azobenzene moieties [i.e., disperse red 19 (DR19), 2‐position‐substituted DR19, and 2,2′‐position‐substituted DR19] were prepared, and their photoinduced birefringence behavior was examined. These polyurethanes showed nearly the same molecular weights, glass transition temperatures, viscosities, and absorption coefficients at the wavelength of the light used to induce the photoresponse. Irradiation of these polymer films with a linearly polarized Ar+ laser induced birefringence due to reorientation of the azobenzene moieties through multiple trans‐cis‐trans isomerization cycles. Despite the slight difference in the chemical structure of the azobenzene moiety, a large difference in the growth behavior of the photoinduced birefringence was observed among these polymers. Because of the small differences in the characteristics of these polymers, we concluded that the isomerization behavior of the azobenzene moiety was the main factor for the results obtained in this study. In addition, the saturated value of the induced birefringence differed to a great extent among these polymers. It was suggested that such a phenomenon could be related to the reorientation behavior induced by the introduction of two methyl groups. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 17–22, 2002
Dielectric and mechanical properties of polystyrene/acrylonitrile–butadiene rubber blends
Authors: Abd‐El‐Messieh S. L. , Eid M. A. M. , Hussein A. I. 
Published: October 2002

AbstractThe dielectric and mechanical properties of polystyrene(PS)/acrylonitrile–butadiene rubber (NBR) blends were studied with the aim of improving the insulation properties of NBR. Compatibility investigations, performed with viscosity and dielectric methods and confirmed with the calculated heat of mixing, indicated that such blends were incompatible. To overcome the problem of phase separation between NBR and PS, we chose epoxidized soya bean oil to act as a compatibilizer and added 3% to the blends under investigation. This led to the conclusion that a sample containing 10% PS (either pure or scrap) possessed the most suitable electrical and mechanical properties. For this reason, the sample was chosen for studying the effect of the addition of three types of fillers (quartz, talc, and calcium carbonate) in increasing quantities (up to 80 phr) on the dielectric and mechanical properties. The variation of the dielectric properties with temperature (20–60°C) was also investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 540–552, 2002
Studies on some acrylamido polymers and copolymer as stabilizers for nitrocellulose
Authors: Hassan M. A. , Shehata A. B. 
Published: October 2002

Abstractpara‐Phenylene diamine was reacted with diethylmalonate and the product was reacted with acryloyl chloride to obtain the corresponding acrylamido malonanilide monomer. para‐Nitro aniline was also reacted with acryloyl chloride to obtain the corresponding monomer. The two monomers were homopolymerized and then copolymerized. The obtained homopolymers and the copolymer were mixed with nitrocellulose and evaluated using thermal analysis and Bergmann–Junk techniques as propellant stabilizers in comparison with the common stabilizer, centralite 1. It was found that the homopolymer containing the p‐nitro group is a superior stabilizer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2808–2819, 2002
Cure kinetics of the cardanyl acrylate–styrene system using isothermal differential scanning calorimetry
Authors: Nguyen Le Huong , Koerner Hilmar , Lederer Klaus 
Published: October 2002

AbstractThe curing kinetics of styrene (30 wt %) and cardanyl acrylate (70 wt %), which was synthesized from cardanol and acryloyl chloride, was investigated by differential scanning calorimetry under isothermal condition. The method allows determination of the most suitable kinetic model and corresponding parameters. All kinetic parameters including the reaction order, activation energy Ea and kinetic rate constant were evaluated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2034–2039, 2002
Electrically conductive semi‐IPNs based on polyaniline and crosslinked polyvinylacetate
Authors: Ma Junqing , Song Huihong , Frisch Harry L. , Maaref Shahin , Sun Sam. S. 
Published: October 2002

AbstractElectrically conductive semi‐IPNs based on polyaniline and crosslinked polyvinylacetate were prepared. Polyaniline successfully percolated through the crosslinked PVAc networks and the resulting semi‐IPNs show a continuous network morphology. The conductivity of the semi‐IPN increases with increasing content of polyaniline and increasing acidity used during the polymerization of the polyaniline. The conductivity of the semi‐IPN is 0.13 S/cm, with the highest polyaniline content of 19.3 wt %. The depression of polyaniline with temperature change is smallest followed by the depression of semi‐IPN of the polyaniline/crosslinked polyvinylacetate, which is considerably smaller than the depression of crosslinked polyvinylacetate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2287–2293, 2002
One‐step, one‐pot photoinitiation of free radical and free radical promoted cationic polymerizations
Authors: Degirmenci M. , Hepuzer Y. , Yagci Y. 
Published: October 2002

AbstractWe describe here a novel approach to photoinitiate free radical and cationic polymerizations concurrently, involving the use of benzoin in conjunction with an onium salt such as diphenyl iodonium or N‐alkoxy pyridinium salt. On photolysis, benzoyl radicals formed from the decomposition of benzoin initiate free radical polymerization of methyl methacrylate. The hydroxy benzyl radicals formed concomitantly are readily oxidized to the corresponding cation by the onium salt to initiate cationic polymerization of cyclohexene oxide in the same system. Evidence for two independent polymerizations was obtained from studies involving gel permeation chromatography, extractions, and infrared and proton nuclear magnetic resonance analysis of the polymers. The effect of the type of the onium salt on each polymerization was also investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2389–2395, 2002
Synthesis, characterization, and chelating properties of the polymacromonomer: Poly[(ethyleneglycol) methyl ether methacrylate]
Authors: Amalia Pooley S. , Rivas Bernabé L. , Maureira Antonio E. 
Published: October 2002

AbstractThe radical polymerization of the macromonomer poly(ethyleneglycol) methyl ether methacrylate with ammonium persulfate at 60°C was carried out. The polymer was completely soluble in water. Yield was 75%. The polymacromonomer was characterized by Fourier transform infrared, proton nuclear magnetic resonance (NMR), and 13C NMR spectroscopy. Mn, Mw, and the polydispersity were determined by gel permeation chromatography. The polymacromonomer showed a high thermal stability with a TDT50% of 420°C. The metal ion binding capacity of this polychelatogen with respect to different metal ions was investigated through the liquid‐phase polymer‐based retention (LPR) technique. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2929–2934, 2002
Preparation and characterization of bismaleimide (N,N′‐bismaleimido‐4,4′‐diphenyl methane)–unsaturated polyester modified epoxy intercrosslinked matrices
Authors: Dinakaran K. , Alagar M. 
Published: October 2002

AbstractAn intercrosslinked network of unsaturated polyester–bismaleimide modified epoxy matrix systems was developed. Epoxy systems modified with 10, 20, and 30% (by weight) of unsaturated polyester were made by using epoxy resin and unsaturated polyester with benzoyl peroxide and diaminodiphenylmethane as curing agents. The reaction between unsaturated polyester and epoxy resin was confirmed by IR spectral studies. The unsaturated polyester toughened epoxy systems were further modified with 5, 10, and 15% (by weightt) of bismaleimide (BMI). The matrices, in the form of castings, were characterized for their mechanical properties. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) of the matrix samples were performed to determine the glass transition temperature (Tg) and thermal degradation temperature of the systems, respectively. Mechanical properties, viz: tensile strength, flexural strength, and plain strain fracture toughness of intercrosslinked epoxy systems, were studied by ASTM methods. Data obtained from mechanical and thermal studies indicated that the introduction of unsaturated polyester into epoxy resin improves toughness but with a reduction in glass transition, whereas the incorporation of bismaleimide into epoxy resin improved both mechanical strength and thermal behavior of epoxy resin. The introduction of bismaleimide into unsaturated polyester‐modified epoxy resin altered thermomechanical properties according to their percentage concentration. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2853–2861, 2002
Controlled release of biocides in solid wood. III. Preparation and characterization of surfactant‐free nanoparticles
Authors: Liu Y. , Laks P. , Heiden P. 
Published: October 2002

AbstractPolymeric nanoparticles containing the fungicides tebuconazole and chlorothalonil were prepared by a simple, surfactant‐free method and found to have significantly smaller median particle diameters and more stable aqueous suspensions than their surfactant‐stabilized counterparts. These more stable suspensions were delivered into southern yellow pine and birch wood with greater efficiency than the equivalent surfactant‐stabilized nanoparticle suspensions. We found that the suspensions protected the treated wood against fungal attack by Gloeophyllum trabeum, a common brown rot wood decay fungus, and Trametes versicolor, a common white rot wood decay fungus, at low tebuconazole and chlorothalonil contents in the wood. Southern pine lost 5% or less of its mass after 55 days of exposure to G. trabeum when the tebuconazole or chlorothalonil content in the wood was only 0.4 kg/m3, while a tebuconazole or chlorothalonil content of 0.8 kg/m3 in birch wood was sufficient to bring its mass loss to less than 5% after 55 days of exposure to T. versicolor. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 615–621, 2002
Synthesis and characterization of starch‐poly(methyl methacrylate) graft copolymers
Authors: Çelik Meltem , Saçak Mehmet 
Published: October 2002

AbstractThe graft copolymerization was carried out by methyl methacrylate with starch in which azobisisobutyronitrile was used as an initiator. The grafting reactions were carried out within a 65–95°C temperature range, and the effect of the monomer, initiator concentrations, and the amount of starch on the graft yield were also investigated. The maximum graft yield was obtained at a azobisisobutyronitrile concentration of 2.0 × 10−3 mol/L. The overall rate activation energy of the reaction was found to be 89.42 kJ/mol. The grafted starches were characterized with infrared spectroscopy, scanning electron microscopy, and thermogravimetry. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 53–57, 2002
Enhanced strain hardening in elongational viscosity for HDPE/crosslinked HDPE blend. II. Processability of thermoforming
Authors: Yamaguchi Masayuki , Suzuki Ken‐Ichi 
Published: October 2002

AbstractRheological properties and processability of thermoforming were studied for high‐density polyethylene (HDPE) and a blend of HDPE with crosslinked HDPE (xHDPE). Blending the xHDPE, which enhances melt strength and strain hardening in elongational viscosity of HDPE, helps the sheet avoid sagging in thermoforming. Moreover, the product of the blend obtained by vacuum forming has uniform wall thickness. Melt strength and strain hardening of the blend were, however, depressed by a processing history in a single‐screw extruder, whereas reprocessing by a two‐roll mill enhanced the melt strength again. It is considered that the processing history by a single‐screw extruder, in which shear‐dominant flow takes place, depresses the trapped entanglements between network chain of xHDPE and linear HDPE molecules, and results in low level of melt strength. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 79–83, 2002
Rheological characterization of cellulose solutions in N‐methyl morpholine N‐oxide monohydrate
Authors: Chae Dong Wook , Kim Byoung Chul , Lee Wha Seop 
Published: October 2002

AbstractThree different modes of rheological properties were measured on 11 and 13 wt % solutions of cellulose in N‐methyl morpholine N‐oxide (NMMO) monohydrate, in which concentration range lyocell fibers of much reduced fibrillation are preferably produced. The dynamic rheological responses revealed that the Cox–Merz rule did not hold for these cellulose solutions. Both cellulose solutions showed a shear thinning behavior over the shear rate measured at 85, 95, 105, and 115°C. However, 13 wt % solution gave rise to yield behavior at 85ºC. The power law index ranged from 0.36 to 0.58. First normal stress difference (N1) was increased with lowering temperature and with increasing concentration as expected. Plotting N1 vs shear stress (τω) gave almost a master curve independent of temperature and concentration, whose slope was about 0.93 for both cellulose solutions over the shear rate range observed (τω > 500 Pa). In addition, the cellulose solutions gave high values of recoverable shear strain (SR), ranging from 60 to 100. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 216–222, 2002
Morphology and mechanical properties of polypropylene/maleated styrene–butadiene–styrene triblock copolymer blends
Authors: Wilhelm Helena Maria , Felisberti Maria Isabel 
Published: October 2002

AbstractThe morphology and mechanical properties of blends of isotactic polypropylene (i‐PP) and a maleated butadiene–styrene–butadiene triblock copolymer with maleic anhydride (SBS–MAH), i‐PP/SBS–MAH, were investigated and compared with those of corresponding blends of i‐PP and a styrene–butadiene–styrene triblock copolymer (SBS), i‐PP/SBS. The blends were prepared in a mixer at 190°C with 5–25 wt % elastomer compositions. The blends exhibited a two‐phase morphology with a disperse elastomer phase in the continuous i‐PP matrix. The size and shape of the elastomer particles and the mechanical properties of the blends depended on the nature and concentration of the elastomer. The i‐PP/SBS–MAH blends showed an impact strength superior to that of the corresponding i‐PP/SBS blends. These results were attributed to the formation of the graft copolymer during the melt blending, which was verified by Fourier transform infrared. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 359–365, 2002