bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reverse atom transfer radical polymerization of methyl methacrylate in different solvents
Authors: Pan Kai , Jiang Long , Zhang Juan , Dan Yi 
Published: July 2007

AbstractThe reverse atom transfer radical polymerization of methyl methacrylate was investigated in different solvents: xylene, N,N‐dimethylformamide, and pyridine. The polymerizations were uncontrolled, using 2,2′‐bipyridine as a ligand in xylene and pyridine because the catalyst (CuBr2/2,2′‐bipyridine complex) had poor solubility in the xylene system. In the pyridine system, the solubility of the catalyst increased, but the solvent could complex with CuBr2, which influenced the control of the polymerization. In the N,N‐dimethylformamide system, the catalyst could be dissolved in the solvent completely, but the N(CH3)2 group in N,N‐dimethylformamide could also complex with CuBr2, so the polymerization could not be well controlled. The ligand of 4,4′‐di(5‐nonyl)‐2,2′‐bipyridine was also investigated in xylene; the introduction of the CH(C4H9)2 group enabled the CuBr2/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine complex to easily dissolve in xylene, and the polymerizations were well controlled. The number‐average molecular weight increased linearly with the monomer conversion from 4280 to 14,700. During the whole polymerization, the polydispersities were quite low (1.07–1.10). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Antiwrinkle treatment of cotton fabric with a mixed sol of TEOS‐TTB/DMDHEU
Authors: Huang Kuo‐Shien , Yang Kerh‐Luen , Lin Shyh‐Jer , Lian Wei‐Tsang 
Published: July 2007

AbstractThis research explored the effect of a mixed sol on the physical properties of a treated fabric, and confirmed the crosslinkage of SiO2 and dimethyloldihydroxyethyleneurea (DMDHEU) using Fourier transform infrared(FTIR) spectroscopy and nuclear magnetic resonance (NMR). In the experiment, DMDHEU was applied to a cotton fabric and different mole ratios of tetraethoxysilane (TEOS)/titanium (IV) n‐butoxide (TTB) were added. The mixture was then subjected to immersion, padding, drying, and curing. The results showed that hydrogen bonds had formed between SiO2 and DMDHEU. The treated fabric had improved antiwrinkle properties, tensile‐strength retention, and yellowing degree when the mole ratio of TEOS was increased. By contrast, the softness of the fabric showed the opposite trend. When the mole ratio of TEOS/TTB was set at 10/1, the treated fabric showed a significant reduction of its antiwrinkle properties under both dry and wet conditions. The fabric treated with TEOS/TTB was superior to the traditionally treated fabric in terms of its ultraviolet (UV) light resistance. When the mole ratio of TEOS/TTB was 2.5/1 or 5.0/1, the addition of 10% DMDHEU during the treatment of the cotton fabric, followed by drying for 5 min at 80°C and curing at 150°C for 2 min, resulted in the fabric having improved and more balanced physical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Friction and wear properties of NBR/PVC composites
Authors: Huang Xinwu , Tian Nong , Wang Tingmei , Wang Kun , Xue Qunji 
Published: July 2007

AbstractAcrylonitrial butadiene rubber (NBR)/Polyvinyl chloride (PVC) composites with different PVC content were prepared. The effect of PVC content on the mechanical strength and tribological properties of the NBR/PVC composites was investigated. The morphologies of the worn traces and debris of NBR/PVC composites and worn traces of mating ball were observed using a scanning electron microscope (SEM). It was found that the friction and wear of NBR/PVC was lower than that of NBR without PVC. The NBR/PVC composite with 30% PVC content showed the best synthetic mechanical and tribological properties. The inferior elastic properties and the lesser deformation under the applied load of composites with PVC resulted in hysteric force and adhesion force decrease, which leading to a lower friction and wear of NBR/PVC composites. The frictional failure unit of NBR70/PVC30 composite being smaller should be an important reason of the wear of the composite being lowest. The lubricating effect of PVC played an important role in decreasing the friction coefficient and wear of NBR/PVC composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Esterification effect of maleic anhydride on swelling properties of natural fiber/high density polyethylene composites
Authors: Naik J. B. , Mishra S. 
Published: July 2007

AbstractThe natural fibers (banana, hemp, and sisal) and high density polyethylene were taken for the preparation of natural fiber/polymer composites in different ratios of 40 : 60 and 45 : 55 (w/w). These fibers were esterified with maleic anhydride (MA) and the effect of esterification of MA was studied on swelling properties in terms of absorption of water, at ambient temperature, and steam. It was found that the steam penetrates more within lesserperiod of time than water at ambient temperature. Untreated fiber composites show more absorption of steam and water in comparison to MA‐treated fiber composites. The more absorption of water was found in hemp fiber composites and less in sisal fiber composites. Steam absorption in MA‐treated and untreated fiber composites are higher than the water absorption in respective fiber composites. The natural fiber/polymer composites containing low amount of fibers show less absorption of steam and water at ambient temperature than the composites containing more amount of fibers in respective fiber composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Moisture diffusion into palm/polypropylene composites in sodium chloride solutions
Authors: Kahraman Ramazan , Abu‐Sharkh Basel F. 
Published: July 2007

AbstractA previous study showed that it was feasible to use wood fibers obtained from palm‐tree branches to reinforce polypropylene. It was the objective of this study to investigate the moisture‐sorption characteristics of palm‐fiber/polypropylene composites and the effect of using a compatibilizer on that important material property. The results of the investigation showed that the amount of moisture absorbed at saturation by polypropylene during immersion in distilled water and various salt solutions increased significantly with the introduction of palm fiber into the polymer. On the other hand, the use of maleated (maleic anhydride modified) polypropylene (Epolene E‐43) as the compatibilizer did not have a significant effect on the amount of moisture intake of palm/polypropylene composites at saturation. However, there was a significant change in the moisture‐diffusion rate with the incorporation of the Epolene E‐43 compatibilizer into the composites: the compatibilizer resulted in a significant increase in the diffusion rate. The moisture diffusivity was not affected by the solution type for the palm/polypropylene composite specimens without any compatibilizer, but some increase in the mass diffusivity was observed as the purity of the solution increased (as the salt concentration decreased) when the Epolene E‐43 compatibilizer was used in the palm/polypropylene composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Influence of electric and mechanical forces on the oxidation kinetics and electroconductive polyisoprene composition properties
Authors: Gul' V. E. , Kirsh I. A. , Kvasnikova E. V. , Zabulonov D. U. , Soina M. V. , Zaikov G. E. 
Published: July 2007

AbstractThe investigation results of the simultaneous effect of electric current and tensile deformation on the oxidation processes and electroconductive polyisoprene composition (EPIC) properties are presented in the study. The effects of the EPIC oxidation process under the conditions of complex factor action, consisting of the gaseous product emission and decrease of the oxidation rate at the final stage of the experiment, were disclosed. It was found out that the change in the electric resistance of EPIC aging with time was characterized by three sections: decrease, constant value area, and increase of the electric resistance. It was demonstrated that the values of the electric resistance and duration of the above sections depended on the deformation temperature and extent. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Crystallization behavior of carbon nanofiber/linear low density polyethylene nanocomposites
Authors: Lee Sungho , Kim Myung‐Soo , Ogale Amod A. 
Published: July 2007

AbstractCrystallization behavior of LLDPE nanocomposites is reported in the presence of three types of carbon nanofibers (CNFs) (MJ, PR‐19, and PR‐24). During nonisothermal crystallization studies, all three crystalline melting peaks for LLDPE matrix were observed in the presence of PR‐19 nanofibers (up to 15 wt % content), but only the high‐ and low‐temperature peaks were observed in the presence MJ nanofibers. The broad melting peak at low‐temperature became bigger, suggesting an increase in the relative content of thinner lamellae in the presence of MJ nanofibers. TEM results of nanocomposites revealed transcrystallinity of LLDPE on the surface of CNFs, and a slightly broader distribution of lamellar thickness. STEM studies revealed a rougher surface morphology of the MJ nanofibers relative to that of PR nanofibers. Also, BET studies confirmed a larger specific surface area of MJ nanofibers relative to that of PR nanofibers, suggesting that the larger and the rougher surface of MJ nanofibers contributes toward the different crystallization behavior of MJ/LLDPE nanocomposites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Studies on the electrical diffusivities of mono‐carboxylates through heterogeneous anion exchange membranes
Authors: Balaji V. , Adhikary S. K. , Ray P. 
Published: July 2007

AbstractHeterogeneous anion exchange membranes have been prepared by solution casting technique with poly (vinyl chloride) (PVC) as inert binder and anion exchange resin (−300 + 400 mesh) by varying their blend ratio from 60 : 40 to 30 : 70. The membranes were characterized with respect to their physical, mechanical, and electrochemical behavior. The transport behavior of such membranes was studied in the solutions of different homologous monocarboxylate salts starting from formate to butyrate. Membrane conductance values, in conjunction with the solution conductance, were used to determine the isoconductance points following the microheterogeneous model developed by Zabolotsky and Nikonenko, J Membr Sci 1993, 79, 181. From the electro conductivity (κ) and exchange capacity (Q) of the joint gel phase, the diffusion coefficients of different carboxylate anions have been determined. The specific conductivities of the joint gel phase decreases in the order κ formate > κ acetate > κ propionate > κ butyrate. For any specific carboxylate counter ion, the κ70 > κ60 > κ50 > κ40. For any particular resin loading the diffusion coefficient in membrane for formate > acetate > propionate > butyrate. The membranes studied here (varying in their blend ratios) may be synchronized by nearly same heterogeneity factor β of value 0.38 ± 0.04. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Filmogen organic–inorganic hybrids obtained by sol–gel in the presence of cationic polymer
Authors: Donescu Dan , Serban Sever , Uricanu Violeta , Duits Michel , Perichaud Alain , Olteanu Mihaela , Spiroiu Manuela , Vasilescu Marilena 
Published: July 2007

AbstractSelf‐standing and coated‐on‐glass films were prepared from polymer–inorganic ormosils, using the cationic polymer poly(methacrylamide propyl quaternarydimethyldodecyl bromide). The inorganic compound was grown in sol–gel reactions based on methyltriethoxysilane (MeTES), with or without addition of the titanium‐precursor: tetraisopropyl orthotitanate. As evidenced by thermogravimetric analysis and differential scanning calorimetry data, the thermal properties of the films are highly dependent on the internal morphology. Inorganic granules with a TiO2 rich shell have a more polar surface, which stimulates stronger electrostatic interactions with the polymer, hence, a reduced mobility for the amino end and a smaller probability to have amino ends engaged in interactions at the surface of the granules. Coated‐on‐glass films drawn from pure cationic polymer suffer from partial dewetting. Topographic and force‐versus‐distance recordings using atomic force microscopy showed a change in the energy balance and no dewetting regions were encountered for polymer/MeTES based composites. However, because of nongrafted polymer, these films are not immune at washing with water/ acetone. Explorations of antibacterial activity against the gram‐negative bacteria, Pseudomonas aeruginosa, were done using ormosil films with alkoxysilanes combinations. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Antimicrobial finishing of cellulose with incorporation of aminopyridinium salts to reactive and direct dyed fabrics
Authors: Zhao Tao , Sun Gang 
Published: July 2007

AbstractThree quaternary ammonium salts namely 4‐amino‐laurylpyridinium chloride, 4‐benzoylamino‐1‐dodecylpyridinium bromide, and 4‐(1‐naphthoyl) amino‐1‐dodecylpyridinium bromide were employed in antimicrobial finishing of dyed and undyed cotton fabrics. The intermolecular interactions between the dyes and the aminopyridinium salts, and their impact on the exhaustions of salts on the dyed fabrics were discussed. The quaternary ammonium salts could form ionic interactions with sulfonate groups on the dyed cotton fibers, which contribute to higher exhaustion uptakes of the salts and better antimicrobial activities against Escherichia coli of the dyed cotton fabrics compared with that of the undyed sample. However, the washing durability of the antimicrobial functions on the finished cotton fabrics was still low because of easy dissociation of the ionic interactions in water. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Morphological features and melting behavior of nanocomposites based on isotactic polypropylene and multiwalled carbon nanotubes
Authors: Avila‐Orta Carlos A. , Medellín‐Rodríguez Francisco J. , Dávila‐Rodríguez Mario V. , Aguirre‐Figueroa Yrayda A. , Yoon Kyunghwan , Hsiao Benjamin S. 
Published: July 2007

AbstractNanocomposites based on low molar mass isotactic polypropylene (iPP) and a low concentrations (1–2 wt %) of multiwalled carbon nanotubes (MWCNTs) were studied using thermal analysis, optical and electronic microscopy, and X‐ray diffraction/scattering techniques. It was first determined that MWCNT decrease induction time and act as nucleating agents of the iPP crystals during nonisothermal crystallization. One of the consequences of the nucleation effect was that the original spherulitic morphology of iPP was transformed into a fibrillar‐like. The corresponding long period of the original well‐defined lamellar structure slightly increased suggesting the formation of thicker crystals in samples containing MWCNT. The nature of the α‐iPP crystalline structure was not affected by MWCNT. After nonisothermal crystallization, two melting endotherms were present during thermal scanning of the iPP/MWCNT nanocomposites their proportion changing with the heating rate. After resolving the total DSC signal in its components using MDSC, the overall evolution of such behavior could be explained in terms of the melting/recrystallization mechanism. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Toughening and compatibilization of polyphenylene sulfide/nylon 66 blends with SEBS and maleic anhydride grafted SEBS triblock copolymers
Authors: Tang Weihua , Hu Xiaoyi , Tang Jian , Jin Riguang 
Published: July 2007

AbstractIn this study, styrene‐b‐ethylene/butylene‐b‐styrene triblock copolymer (SEBS) and maleic anhydride grafted SEBS (SEBS‐g‐MA) were used as compatibilizers for the blends of polyphenylene sulfide/nylon 66 (PPS/PA66). The mechanical properties, including impact and tensile properties and morphology of the blends, were investigated by mechanical properties measurements and scanning electron microscopy. Impact measurements indicated that the impact strength of the blends increases slowly with elastomer (SEBS and SEBS‐g‐MA) content upto 20 wt %; thereafter, it increases sharply with increasing elastomer content. The impact energy of the elastomer‐compatibilized PPS/PA66 blends exceeded that of pure nylon 66, implying that the nylon 66 can be further toughened by the incorporation of brittle PPS minor phase in the presence of SEBS or SEBS‐g‐MA. The compatibilization efficiency of SEBS‐g‐MA for nylon‐rich PPS/PA66 was found to be higher than SEBS due to the in situ forming SEBS interphase between PPS and nylon 66. The correlation between the impact property and morphology of the SEBS‐g‐MA compatibilized PPS/PA66 blends is discussed. The excellent impact strength of the nylon‐rich blends resulted from shield yielding of the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation and characterization of soluble polyaniline
Authors: Dan Ananya , Sengupta P. K. 
Published: July 2007

AbstractPolyaniline, which is soluble in common organic solvents, has been synthesized through the oxidative chemical polymerization of aniline in the presence of benzene diazonium chloride salt in an aqueous HCl acid medium. The blue‐black polyaniline thus prepared exists in a lower oxidation state than emeraldine. An X‐ray photoelectron spectroscopy study has shown that the intrinsic oxidation state of the polymer is 0.38. An elemental analysis has shown that the fractional doping level or degree of oxidation of the blue‐black polyaniline is 0.26. The product is believed to consist of a lower number of imine nitrogens in comparison with the polyemeraldine base. This fact is also corroborated by the lower electrical conductivity of the polymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Convenient and efficient synthesis of a lanthanide3+‐coordinated, diethylene triamine pentaacetic acid labeled biopolymer as an assay for the cholecystokinin B receptor
Authors: Gao F. , Handl H. , Vagner J. , Hruby V. , Gillies R. 
Published: July 2007

AbstractTo develop an assay for the cholecystokinin B receptor with an Eu3+‐labeled cholecystokinin peptide via a diethylene triamine pentaacetic acid chelating linker, a commercial dianhydride diethylene triamine pentaacetic acid precursor was directly attached to the N‐terminus of cholecystokinin peptides by a solid‐phase synthesis method with a satisfactory yield and purity after reverse‐phase high‐performance liquid chromatography separation. Lanthanide was then coordinated to the peptide via a diethylene triamine pentaacetic acid bifunctional agent. This method is a useful approach to the large‐scale synthesis of lanthanide3+‐coordinated, diethylene triamine pentaacetic acid labeled biopolymers. This research provides not only a simple and convenient method for the preparation of lanthanide‐based peptide ligand libraries but also possible lanthanide‐based high‐throughput screening of peptide receptors with a time‐resolved fluorescence assay system. Five biopolymers were synthesized and characterized with high‐resolution electrospray ionization in this study. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Mutant tumor necrosis factor receptor associated with tumor necrosis factor receptor–associated periodic syndrome is altered antigenically and is retained within patients' leukocytes
Authors: Todd Ian , Radford Paul M. , Daffa Noura , Bainbridge Susan E. , Powell Richard J. , Tighe Patrick J. 
Published: July 2007

AbstractObjectiveTo investigate the effect of mutations in tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) in TNFR‐associated periodic syndrome (TRAPS) on the binding of anti‐TNFRSF1A monoclonal antibodies (mAb), and to investigate the subcellular distribution of mutant versus wild‐type (WT) TNFRSF1A in patients with TRAPS.MethodsHEK 293 cells transfected with WT and/or mutant TNFRSF1A were used to investigate the interaction of anti‐TNFRSF1A mAb with the WT and mutant proteins. Monoclonal antibodies that differentially bound to C33Y TNFRSF1A were used to investigate the distribution of WT and mutant TNFRSF1A in TRAPS patients with the C33Y mutation.ResultsWe identified a mAb whose binding to TNFRSF1A was completely abolished by the C33Y or C52F TRAPS‐associated mutations, whereas other mutations (T50M, C88Y, R92Q) had lesser effects on the binding of this mAb. A different mAb was found to bind efficiently to all of the mutant forms of TNFRSF1A examined as well as to the WT receptor. Exploitation of the differential binding properties of these mAb indicated that mutant (as distinct from WT) TNFRSF1A showed abnormal intracellular retention in the neutrophils of TRAPS patients with the C33Y mutation, with little if any expression of mutant TNFRSF1A on the cell surface or as soluble receptor in plasma.ConclusionTRAPS‐associated mutant TNFRSF1A has an antigenically altered structure and shows abnormal retention in the leukocytes of patients with TRAPS, which is consistent with previous findings from in vitro and transgenic model systems. This is consistent with a misfolded protein response contributing to the pathophysiology of TRAPS.
Evidence that the p38 MAP kinase pathway is dysregulated in HLA–B27–expressing human monocytic cells: Correlation with HLA–B27 misfolding
Authors: Sahlberg Anna S. , Penttinen Markus A. , Heiskanen Kaisa M. , Colbert Robert A. , Sistonen Lea , Granfors Kaisa 
Published: July 2007

AbstractObjectiveTo investigate the cause of the enhanced intracellular replication of Salmonella enteritidis in HLA–B27–transfected U937 human monocytic cells and the contribution of HLA–B27 heavy chain (HC) misfolding.MethodsU937 monocytic cell transfectants stably expressing pSV2neo resistant vector (mock), wild‐type HLA–B27, or mutated HLA–B27 HCs with amino acid substitutions in the B pocket were differentiated, infected with S enteritidis, and treated with signaling pathway inhibitors or specific p38 small interfering RNA (siRNA). The numbers of living intracellular bacteria were determined with the colony‐forming unit method. To visualize S enteritidis, the bacteria were transformed with green fluorescent protein, and studied by microscopy.ResultsTreatment with the p38 MAPK inhibitors or with p38 siRNA enhanced the replication of S enteritidis in U937 transfectants, whereas the other inhibitors had no effect. In mock‐transfected cells and in cells expressing the mutated B27 HCs in which the misfolding had been corrected, p38 inhibitors impaired their ability to resist the replication of bacteria (mock, B27.A2B, B27.E45M, and B27.C67A). In contrast, the number of intracellular bacteria was not significantly increased in p38 inhibitor‐treated cells expressing misfolded B27 HCs (B27g, B27cDNA, and B27.H9F).ConclusionOur results show that p38 activity plays a crucial role in controlling intracellular S enteritidis in U937 cells. Enhanced replication of bacteria in B27‐expressing cells requires that the HCs contain glutamic acid at position 45 and cysteine at position 67. Furthermore, in transfectants expressing misfolded B27 HCs, p38 inhibition had no significant effect on bacterial replication, suggesting that in these cells, the p38 pathway may not function properly.