bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiation‐processed styrene–butadiene‐co‐ethylene– propylene diene rubber blends: Compatibility and swelling studies
Authors: Dubey K. A. , Bhardwaj Y. K. , Chaudhari C. V. , Sabharwal S. 
Published: January 2006

AbstractRadiation‐induced compatibility behavior of SBR–EPDM blends of different composition has been investigated using dilute solution viscometry. The results show that at a threshold dose of 10 kGy, good interaction between the components of the blends is achieved. Higher radiation doses lead to formation of crosslinked three‐dimensional copolymer network, whose swelling depends on the radiation dose imparted. The anomalous diffusion of solvent into the gels was confirmed by rigorous treatment of the swelling data. Permeation data agreement with the series model indicated that in SBR–EPDM blends EPDM exists as continuous phase and SBR as dispersed phase. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3638–3649, 2006
Nonisothermal crystallization kinetics of poly(butylene terephthalate)/montmorillonite nanocomposites
Authors: Wu Defeng , Zhou Chixing , Fan Xie , Mao Dalian , Bian Zhang 
Published: January 2006

AbstractThe melt intercalation method was employed to prepare poly(butylene terephthalate) (PBT)/montmorillonite (MMT) nanocomposites, and the microstructures were characterized with X‐ray diffraction and transmission electron microscopy. Then, the nonisothermal crystallization behavior of the nanocomposites was studied with differential scanning calorimetry (DSC). The DSC results showed that the exothermic peaks for the nanocomposites distinctly shifted to lower temperatures at various cooling rates in comparison with that for pure PBT, and with increasing MMT content, the peak crystallization temperature of the PBT/MMT hybrids declined gradually. The nonisothermal crystallization kinetics were analyzed by the Avrami, Jeziorny, Ozawa, and Mo methods on the basis of the DSC data. The results revealed that very small amounts of clay (1 wt %) could accelerate the crystallization process, whereas higher clay loadings reduced the rate of crystallization. In addition, the activation energy for the transport of the macromolecular segments to the growing surface was determined by the Kissinger method. The results clearly indicated that the hybrids with small amounts of clay presented lower activation energy than PBT, whereas those with higher clay loadings showed higher activation energy. The MMT content and the crystallization conditions as well as the nature of the matrix itself affected the crystallization behavior of the hybrids. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3257–3265, 2006
Preparation, modification, and characterization of acrylic cements
Authors: Basgorenay Burcu , Ulubayram Kezban , Serbetci Kemal , Onurhan Erdal , Hasirci Nesrin 
Published: January 2006

AbstractAcrylic cements with different compositions were prepared by mixing the solid part (composed of poly(methyl methacrylate), PMMA, and benzoyl peroxide, BPO) and the liquid part (composed of methyl methacrylate, MMA, and N,N‐dimethyl‐p‐toluidine, DMPT), modified by addition of hydroxyapatite (HA) and ammonium nitrate (AN) and characterized by measuring thermal and mechanical properties. Three sets of samples were prepared. For B‐group, the total amount of solid including HA was constant but the PMMA to HA ratio was varied. For C‐group, polymer/monomer ratio was constant and varying amounts of HA was added. For D‐group, polymer/monomer ratio was kept constant and AN was added in varying amounts. Effects of these composition changes on the properties of the cement such as setting time, curing temperature, tensile and compression strength, and deformation were examined. For B‐group samples, no linear change was observed in thermal (curing temperatures were all quite high) and mechanical (between 27 and 19 MPa for tensile, and 98 and 116 MPa for compression strength) properties upon change of HA content with change in solid/liquid ratio. For C and D‐group samples, a continuous decrease in curing temperature from 114 to 101°C and from 94 to 73°C was observed upon increasing HA and AN contents, respectively. Also, a linear relation was observed in compression strength (from 98 to 111 MPa) and in tensile strength (from 27 to 21 MPa) upon HA addition, and in the compression strength (from 103 to 85 MPa) and in the tensile strength (from 22 to 17 MPa) with NA addition. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3631–3637, 2006
Comparison of the curing kinetics of the RTM6 epoxy resin system using differential scanning calorimetry and a microwave‐heated calorimeter
Authors: Navabpour Parnia , Nesbitt Alan , Degamber B. , Fernando G. , Mann Tim , Day Richard 
Published: January 2006

AbstractThe cure of a commercial epoxy resin system, RTM6, was investigated using a conventional differential scanning calorimeter and a microwave‐heated calorimeter. Two curing methods, dynamic and isothermal, were carried out and the degree of cure and the reaction rates were compared. Several kinetics models ranging from a simple nth order model to more complicated models comprising nth order and autocatalytic kinetics models were used to describe the curing processes. The results showed that the resin cured isothermally showed similar cure times and final degree of cure using both conventional and microwave heating methods, suggesting similar curing mechanisms using both heating methods. The dynamic curing data were, however, different using two heating methods, possibly suggesting different curing mechanisms. Near‐infrared spectroscopy showed that in the dynamic curing of RTM6 using microwave heating, the epoxy‐amine reaction proceeded more rapidly than did the epoxy‐hydroxyl reaction. This was not the case during conventional curing of this resin. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3658–3668, 2006
Synthesis and characterization of acrylamide and 2‐hydroxylpropyl methacrylate hydrogels for specialty applications
Authors: Chauhan Ghanshyam S. , Chauhan Sandeep , Chauhan Kalpana , Sen Usha 
Published: January 2006

AbstractTo modify acrylamide (AAm) hydrogels for specialty applications, it was copolymerized with 2‐Hydroxypropyl methacrylate (HPMA) in different molar ratio at 25°C in 1:1 water–acetone solvent system, using ammonium persulphate (APS) and N,N,N,N‐tetramethyl ethylene diamine (TEMED) initiator–accelerator system. Two series of hydrogels were thus prepared using two different crosslinkers—ethylene glycol dimethacrylate (EGDMA) and N,N‐methylene bisacrylamide (N,N‐MBAAm). To affect property profile of the hydrogels, concentration of HPMA was varied over a range of five concentrations from 3.5 to 28 mM. Hydrogels were further functionalized by partial hydrolysis with NaOH and Hofmann amide degradation reaction. FTIR, Nitrogen analysis, and SEM were used to establish monomer reactivity and structure relationship of the hydrogels. Metal ion uptake was studied as a function of various structural aspects of the hydrogels. Water uptake behavior of the hydrogels was studied at constant time, temperature, and pH, both pre and post metal loading. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3040–3049, 2006
The shear strength of Calabrian pine (Pinus brutia Ten.) bonded with polyurethane and polyvinyl acetate adhesives
Authors: Burdurlu Erol , Kılıç Yılmaz , Eli̇bol G. Cankız , Kılıç Murat 
Published: January 2006

AbstractIn this study, the change in shear strength on radial and tangential surfaces of Calabrian Pine (Pinus brutia Ten.) wood having different roughness values as the result of sawing with a circular ripsaw, planing and sanding, and bonded with polyurethane (PU) and polyvinyl acetate (PVAc) adhesives at the pressure levels of 3, 6, and 9 kgf/cm2, was studied. Each of the 360 specimens prepared to determine the effect of the variables on bond performance were subjected to shear test in an universal test machine in accordance with the ASTM D 905–98 standards. The values obtained were analyzed statistically and the results were interpreted. The highest shear strength (11.83 N/mm2) for plane of cut was obtained on the tangential surface after sanding and applying PVAc adhesive with a pressing pressure of 9 kgf/cm2. The lowest shear strength (6.01 N/mm2) was obtained in the joinings made on the planed surfaces by using PU adhesive and a pressing pressure of 3 kgf/cm2. The highest shear strength (9.10 N/mm2) on the radial surface was obtained after sanding and applying PVAc adhesive and pressing with a pressure of 6 kgf/cm2. The lowest shear strength (3.76 N/mm2) was obtained in the specimens whose surfaces were sanded and glued with PU adhesive with a pressing pressure of 3 kgf/cm2. In general, in the radial surfaces, just like in the tangential surfaces, the specimens bonded with PVAc exhibited a higher shear strength compared with those glued with PU. According to these results, it is definitely necessary to sand the surfaces prior to the bonding process to have a higher shear strength. The bonding process should be made on the tangential surfaces with higher pressures. The PVAc adhesive should be preferred instead of the PU adhesive. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3050–3061, 2006
Rubber‐toughened polypropylene nanocomposite: Effect of polyethylene octene copolymer on mechanical properties and phase morphology
Authors: Lim J. W. , Hassan A. , Rahmat A. R. , Wahit M. U. 
Published: January 2006

AbstractRubber‐toughened polypropylene (PP)/org‐Montmorillonite (org‐MMT) nanocomposite with polyethylene octene (POE) copolymer were compounded in a twin‐screw extruder at 230°C and injection‐molded. The POE used had 25 wt % 1‐octene content and the weight fraction of POE in the blend was varied in the range of 0–20 wt %. X‐ray diffraction analysis (XRD) revealed that an intercalation org‐MMT silicate layer structure was formed in rubber‐toughened polypropylene nanocomposites (RTPPNC). Izod impact measurements indicated that the addition of POE led to a significant improvement in the impact strength of the RTPPNC, from 6.2 kJ/m2 in untoughened PP nanocomposites to 17.8 kJ/m2 in RTPPNC containing 20 wt % POE. This shows that the POE elastomer was very effective in converting brittle PP nanocomposites into tough nanocomposites. However, the Young's modulus, tensile strength, flexural modulus, and flexural strength of the blends decreased with respect to the PP nanocomposites, as the weight fraction of POE was increased to 20 wt %. Scanning electron microscopy (SEM) was used for the investigation of the phase morphology and rubber particles size. SEM study revealed a two‐phase morphology where POE, as droplets was dispersed finely and uniformly in the PP matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3441–3450, 2006
Preparation of electrorheological active ionomers from poly(2‐hydroxyethyl methacrylate)‐co‐poly(4‐vinyl pyridine)
Authors: Yilmaz Hasim , Unal Halil Ibrahim 
Published: January 2006

AbstractIn this study, synthesis, characterization, partial hydrolysis, and salt formation of poly(2‐hydroxyethyl methacrylate)‐co‐poly(4‐vinyl pyridine), (poly(HEMA)‐co‐poly‐(4‐VP)) copolymers were investigated. The copolymers were synthesized by free radical polymerization using K2S2O8 as an initiator. By varying the monomer/initiator ratio, chain lengths of the copolymers were changed. The copolymers were characterized by gel permeation chromatography (GPC), viscosity measurements, 1H and 13C NMR and FTIR spectroscopies, elemental analysis, and end group analysis methods. The copolymers were partially hydrolyzed by p‐toluene sulfonic acid monohydrate (PTSA·H2O) and washed with LiOH(aq) solution to prepare electrorheological (ER) active ionomers, poly(Li‐HEMA)‐co‐poly(4‐VP). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3540–3548, 2006
Effects of fiber aggregates on the transverse mechanical behavior of commingled PP–glass fiber composites
Authors: Dubouloz‐Monnet F. , Albérola N. D. , Mélé P. 
Published: January 2006

AbstractIn previous articles, mechanical models were proposed to predict the reinforcement effect of polymers by particulates as well as unidirectional fibers over wide ranges of volume fraction of fillers and temperatures. On the basis of image analyses and the definition of representative morphological motifs, these models are able to predict the viscoelastic properties of quasi‐isotropic and unidirectional composites or to extract the behavior of a phase, such as the interphase in filled rubbers or the transcrystalline phase in semicrystalline polymers. In this work, based on a 2D image processing, this approach is extended to predict the viscoelastic properties of commingled PP–glass fiber composites. It is shown that fiber aggregates, composed of fibers and surrounding polymer, might be considered as the reinforcing phase. In addition, the different failure modes of these composites are separated as a function of the volume fraction of fillers or temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3466–3476, 2006
Gas diffusion in branched and crosslinked polymers: A model of treelike clusters
Authors: Khalikov R. M. , Kozlov G. V. , Zaikov G. E. 
Published: January 2006

AbstractThe correctness of the fractal model of treelike clusters for describing the diffusion processes in branched (crosslinked) copolymers is shown. As in the fractal model of gas transport processes, for the copolymers investigated, the main role of diffusivity was to change the connectivity of the macromolecule, characterized by its spectral dimension. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3571–3573, 2006
Effect of magnesium and phosphate ions on the stability of concentrated natural rubber latex and the properties of natural rubber latex–dipped products
Authors: Karunanayake L. , Perera G. M. Priyanthi 
Published: January 2006

AbstractThe presence of Mg2+ ions was found to be a major cause of destabilization of natural rubber (NR) latex. On the other hand, the addition of excess PO ions to remove Mg2+ ions could adversely affect the physical properties of dipped products made of NR latex. A series of concentrated latex samples were treated with varying amounts of Mg2+ and PO ions. Changes with time in the characteristics of the treated latex samples such as mechanical stability time, volatile fatty acid number, and chemical stability time and in the physical properties of the dipped products such as aged and unaged tensile properties were monitored. The latex batch with a PO ion concentration of 30 ppm was found to produce the best‐quality latex and dipped products. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3120–3124, 2006
Enhancement of the optical properties of poly vinyl alcohol by doping with silver nanoparticles
Authors: Badr Y. , Mahmoud M. A. 
Published: January 2006

AbstractPoly vinyl alcohol (PVA) incorporated with different weight percent of Silver nanoparticles (Ag NPs) were prepared. The enhancement factors for each band in the Raman spectra were calculated and the degree of enhancement were found to be increased as the percent of Ag NPs increases up to 0.3%, and thereafter it decreases. Some bands were red shifted while others were blue shifted. The overtones FTIR bands and photoacoustic spectra were recorded and show the same behavior as those bands. The X‐ray diffraction pattern and Raman and photoacoustic spectra showed that PVA has a high degree of crystallinity. The UV–vis spectra of the same samples were red shifted and increase in their intensities up to 0.3% Ag NPs, thereafter the band intensities of the peak corresponding to Ag NPs were diminished. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3608–3614, 2006
Effect of a fatty amine on processing and physical properties of SBR compounds filled with silane–silica particles
Authors: Valentín J. L. , Posadas P. , Marcos‐Fernández A. , Ibarra L. , Rodríguez A. 
Published: January 2006

AbstractThe use of fatty amines, obtained from natural fatty acids, in rubber compounds to improve silica dispersion was evaluated. Fatty amines can interact with the free silanol groups of the bis(3‐triethoxysilyl‐propyl) tetrasulfide (TESPT) silane‐modified silica forming an amine‐modified silica complex, which reduces the hydrophilic nature of the silica surface, minimizing the silica–silica interactions, and reducing the formation of secondary structures of silica. The effect of the addition of different amines and/or polyethylenglycol to SBR compounds loaded with silane‐modified silica was evaluated. Finally, incorporation of fatty amines improved the processability and traction properties of rubber compounds loaded with modified silica. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3222–3229, 2006
Synthesis and characterization of poly(butyl acrylate)/silica and poly(butyl acrylate)/silica/poly(methyl methacrylate) composite particles
Authors: Qi Dong‐Ming , Bao Yong‐Zhong , Huang Zhi‐Ming , Weng Zhi‐Xue 
Published: January 2006

AbstractPoly(butyl acrylate)/poly(methyl methacrylate) (PBA/PMMA) core–shell particles embedded with nanometer‐sized silica particles were prepared by emulsion polymerization of butyl acrylate (BA) in the presence of silica particles preabsorbed with 2,2′‐azobis(2‐amidinopropane)dihydrochloride (AIBA) initiator and subsequent MMA emulsion polymerization in the presence of PBA/silica composite particles. The morphologies of the resulting PBA/silica and PBA/silica/PMMA composite particles were characterized, which showed that AIBA could be absorbed effectively onto silica particles when the pH of the dispersion medium was greater than the isoelectric potential point of silica. The critical amount of AIBA added to have stable dispersion of silica particles increased as the pH of the dispersion medium increased. PBA/silica composite particles prepared by in situ emulsion polymerization using silica preabsorbed with AIBA showed higher silica absorption efficiency than did the PBA/silica composite particles prepared by direct mixing of PBA latex and silica dispersion or by emulsion polymerization in which AIBA was added after the mixing of BA and silica. The PBA/silica composite particles exhibited a raspberrylike morphology, with silica particles “adhered” to the surfaces of the PBA particles, whereas the PBA/silica/PMMA composite latex particles exhibited a sandwich morphology, with silica particles mainly at the interface between the PBA core and the PMMA shell. Subsequently, the PBA/silica/PMMA composite latex obtained had a narrow particle size distribution and good dispersion stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3425–3432, 2006
Effects of particle size on the molecular orientation and birefringence of magnetic nanoparticles/polyimide composites
Authors: Kang Jin Ho , Kim Young Chul , Cho Kilwon , Park Chan Eon 
Published: January 2006

AbstractSize dependency of nanoparticles for birefringence and molecular orientation of nanocomposite films have been studied using a prism coupler and near‐edge X‐ray absorption fine structure spectroscopy (NEXAFS). We synthesized two different sizes of magnetic nanoparticles, Ni0.6Zn0.4Fe2O4. The smaller ones were 6.1 ± 1.3 nm‐diameter nanoparticles showing superparamagnetism and the larger ones were 20.7 ± 6.1 nm‐diameter nanoparticles showing ferrimagnetism. To make nanocomposites, we incorporated these particles into poly(N,N′‐bis(phenoxyphenyl)pyromellitimide) (PMDA‐ODA PI). From the prism coupler study, pristine PI without nanoparticles had higher out‐of‐plane birefringence, which indicated high in‐plane orientation of polyimide. However, the birefringence of PI nanocomposites decreased with the increase of particle content. The birefringence of PI nanocomposite with small nanoparticles was smaller than that of PI nanocomposite with large nanoparticles. The birefringence of PI nanocomposite with 1 wt % of small nanoparticles was reduced to almost half of that of pristine PI due to the decreased orientation of PI molecules. NEXAFS spectra of N K‐edge were the same as the birefringence results. Imide and phenyl rings of pristine PI aligned more parallel to the in‐plane direction, but those of PI with nanoparticles aligned less parallel to the in‐plane direction. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3433–3440, 2006
Structure and properties of polybutadiene/montmorillonite nanocomposites prepared by in situ polymerization
Authors: Liao Mingyi , Zhang Weiqing , Shan Wei , Zhang Yipeng 
Published: January 2006

AbstractPolybutadiene (PB)/Montmorillonite nanocomposites (NCs) were prepared by in situ polymerization through the anionic polymerization technique. The effects of treating method of organophilic MMT (OMMT), the type of OMMT, and the solvent used in polymerization were studied. The structure and properties of NCs were characterized using X‐ray Diffraction (XRD), transmission electron micrograph (TEM), H‐NMR spectrum, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). The consumption of BuLi was varied with different treating methods. The molecular weight distribution of PB added with OMMT (DK1) was wide, and the molecular weight distribution became narrow when OMMT‐DK1B and DK4 were added. OMMT did not disperse stably in cyclohexane, but could form a homogeneous solution in toluene and xylene. XRD and TEM showed that exfoliated NCs were obtained by in situ polymerization through the anionic polymerization technique. From the H‐NMR spectrum of PB and PB/OMMT NCs, it could be seen that the content of 1, 2 units of PB increased ∼100%, while 1, 4 units decreased when 6.2 wt % of OMMT was added. The results of DSC and DMA indicated that Tg and Tdc were increased when compared with those of PB. Both storage modulus and loss modulus were increased with the addition of OMMT, and tan δ was decreased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3615–3621, 2006
Synthesis and physicochemical characterization of amphiphilic block copolymer self‐aggregates formed by poly(ethylene glycol)‐block‐poly(ϵ‐caprolactone)
Authors: Choi Changyong , Chae Su Young , Kim Tai‐Hyoung , Kweon Jung Keon , Cho Chong Su , Jang Mi‐Kyeong , Nah Jae‐Woon 
Published: January 2006

AbstractDiblock copolymers with different poly(ε‐caprolactone) (PCL) block lengths were synthesized by ring‐opening polymerization of ε‐caprolactone in the presence of monomethoxy poly(ethylene glycol) (mPEG‐OH, MW 2000) as initiator. The self‐aggregation behaviors and microscopic characteristics of the diblock copolymer self‐aggregates, prepared by the diafiltration method, were investigated by using 1H NMR, dynamic light scattering (DLS), and fluorescence spectroscopy. The PEG–PCL block copolymers formed the self‐aggregate in an aqueous environment by intra‐ and/or intermolecular association between hydrophobic PCL chains. The critical aggregation concentrations of the block copolymer self‐aggregate became lower with increasing hydrophobic PCL block length. On the other hand, reverse trends of mean hydrodynamic diameters were measured by DLS owing to the increasing bulkiness of the hydrophobic chains and hydrophobic interaction between the PCL microdomains. The partition equilibrium constants (Kv) of pyrene, measured by fluorescence spectroscopy, revealed that the inner core hydrophobicity of the nanoparticles increased with increasing PCL chain length. The aggregation number of PCL chain per one hydrophobic microdomain, investigated by the fluorescence quenching method using cetylpyridinium chloride as a quencher, revealed that 4–20 block copolymer chains were needed to form a hydrophobic microdomain, depending on PCL block length. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3520–3527, 2006