bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of the addition mode of cycloaliphatic diepoxide on the morphology and film properties of crosslinkable core‐shell latex
Authors: Teng Ganghua , Soucek Mark D. , Yang Xiaofan F. , Tallman Dennis E. 
Published: February 2003

AbstractCore‐shell latexes (LAs) designed for crosslinking with cycloaliphatic diepoxide were synthesized. The core contained methyl methacrylate (MMA), butyl acrylate (BA), and 2‐hydroxyethyl methacrylate, and the shell was prepared with MMA, BA, and methacrylic acid. The crosslinker was coemulsified with the monomer and added during the LA preparation or after the polymerization either as an emulsion or in an organic solvent. The morphology of the LA was studied with atomic force microscopy and transmission electron microscopy. We used titration to establish the acid distribution. The water absorption and tensile and viscoelastic properties of the LA films were investigated as a function of the addition mode of the cycloaliphatic diepoxide crosslinker. The solution approach generally provided better mechanical properties than the emulsion approach, and the addition of epoxide during the polymerization lowered the water adsorption and hardness. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 245–257, 2003
Deposition of poly(diphenylamine‐co‐o‐chloroaniline) by pulse potentiostatic method: Growth equation and characterization
Authors: Rajendran V. , Gopalan A. , Buvaneswari R. , Vasudevan T. , Wen Ten‐Chin 
Published: February 2003

AbstractElectrochemical copolymerization of diphenylamine (DPA) with o‐chloroaniline (OCA) was performed in aqueous 4M sulfuric acid using the pulse potentiostatic method (PPSM). By employing the tunable parameters in PPSM, polymeric films were deposited under different conditions. Cyclic voltammetry was used for evaluating the characteristics of the deposited polymeric films. A suitable growth equation for the deposition of polymer, relating the charge associated for the film deposition and the pulse parameters in PPSM, was deduced. Various surface parameters are evaluated. The formation of copolymer during PPSM deposition was revealed through critical analysis of the results. The characteristic differences between the individual homopolymers, poly(diphenylamine) and poly(o‐chloroaniline) and the copolymer, poly(diphenylamine‐co‐o‐chloroaniline), were brought out. The copolymer was also synthesized through a chemical method and characterized through infrared and ultraviolet‐visible spectroscopic analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 389–397, 2003
Effects of an organic phosphorus nucleating agent on crystallization behaviors and mechanical properties of poly(propylene)
Authors: Gui Quande , Xin Zhong , Zhu Weiping , Dai Gance 
Published: February 2003

AbstractThe effects of an organic phosphorus nucleating agent on the crystallization behavior and mechanical properties of poly(propylene) were investigated. As the concentration of nucleating agent increased from 0 to 0.8%, the tensile and flexural strengths of the nucleated poly(propylene) resin increased by 15%, the flexural modulus increased by 35%, the crystallization peak temperature increased by 10°C, and the nucleation density (calculated with the nonlinear Voltrra integral equation) increased by 106 times. Mechanical properties increased with nucleation density. Linear equations between the mechanical properties and the logarithmic nucleation density were revealed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 297–301, 2003
Properties of soy protein isolate/poly(ethylene‐co‐ethyl acrylate‐co‐maleic anhydride) blends
Authors: Zhong Zhikai , Sun Susan X. 
Published: February 2003

AbstractBlends of soy protein isolate (SPI) with 10, 20, 30, 40, and 50% poly(ethylene‐co‐ethyl acrylate‐co‐maleic anhydride) (PEEAMA), with or without addition of 2.0 wt % methylene diphenyl diisocyanate (MDI), were prepared by mixing with an intensive mixer at 150°C for 5 min, and then milling through a 1‐mm sieve. Blends were then compression‐molded into a tensile bar at 140°C. Thermal and mechanical properties and water absorption of the blends were studied by differential scanning calorimetry (DSC), dynamical mechanic analysis (DMA), a test of modulus and tensile strength (with an Instron tensile tester), a water absorption test, and scanning electron microscopy (SEM). The blends showed two composition‐dependent glass transition temperatures. Furthermore, as the SPI content increased, the melting temperature of PEEAMA remained constant but the heat of fusion decreased. These results indicate that SPI and PEEAMA were partially miscible. Morphology observations support these results. Increasing the PEEAMA content resulted in decreases in the modulus and tensile strengths and increases in the elongation and toughness of the blends. Water absorption of the blends also decreased with increased PEEAMA content. Incorporating MDI further decreased the water absorption of the blends. The mechanism of water sorption of SPI was relaxation controlled, and that of the blends was diffusion controlled. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 407–413, 2003
Ways of strengthening biodegradable soy‐dreg plastics
Authors: Zhang Lina , Chen Pu , Huang Jin , Yang Guang , Zheng Lianshuang 
Published: February 2003

AbstractBiodegradable plastics (GSD) based on soy dreg (SD) were prepared by compression‐molding, with glycerol as the plasticizer and glutaraldehyde (GA) as the cross‐linker. The structure and properties of the GSD sheets were investigated by Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), scanning electron microscope (SEM), and tensile test methods. The results indicate that when GA content was 6.8%, the tensile strength (σb) of the sheet reached the maximum value of 14.5 MPa. Moreover, the strength and water resistance of the sheets coated with castor‐oil‐based polyurethane/nitrochitosan interpenetrating network (IPN) coating were significantly enhanced to 24.6 MPa in the dry state and 9.8 MPa in the wet state. Simultaneously, the test of biodegradability of the GSD sheet in a mineral salts medium containing microorganisms and agar proved that GSD could be fully biodegradable. This work has provided a novel way to utilize low‐cost SD to prepare biodegradable plastics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 422–427, 2003
Preparation of micrometer‐sized, monodisperse, magnetic polymer particles
Authors: Okubo M. , Minami H. , Komura T. 
Published: February 2003

AbstractMicrometer‐sized, monodisperse, magnetic composite particles were prepared by heating micrometer‐sized, monodisperse, hollow polystyrene/polydivinylbenzene composite polymer particles at 200°C for 4 h (particles had been dipped in pentacarbonyliron) and then washed in 12 N HCl and water. The hollow polymer particles were produced by seeded polymerization by the dynamic swelling method that was proposed by authors. The magnetic composite particles contained Fe3O4, the content of which was 49% based on total weight, and were attracted easily in water by a 1650 G magnet. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 428–433, 2003
Review on the development of defect‐free and ultrathin‐skinned asymmetric membranes for gas separation through manipulation of phase inversion and rheological factors
Authors: Ismail Ahmad Fauzi , Yean Lai Ping 
Published: February 2003

AbstractDevelopment of high‐performance asymmetric membranes is a major breakthrough in membrane technology. A comprehensive study on original concepts and new advances in membrane formation process is necessary to generate defect‐free and ultrathin‐skinned asymmetric membranes with superior performance for gas separation process. Correlation of rheological factors with primary‐phase inversion process is a novel approach in membrane research that provides a potential platform to improve membrane performance. The former controls general morphology of membrane, whereas the latter further affects molecular orientation in membrane. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 442–451, 2003
Modification of aqueous acrylic–polyurethane via epoxy resin postcrosslinking
Authors: Shi Yuanchang , Wu Youshi , Zhu Zhiqian 
Published: February 2003

AbstractAn epoxy resin (E‐51)‐modified acrylic–polyurethane emulsion with triethylenetetramine (TETA) serving as the postcrosslinking agent was synthesized. The curing reaction between E‐51 and the curing agent TETA during the film‐forming course was monitored and identified by an infrared spectrophotometer. The stabilities of the single‐pack emulsion during the polymerization course as well as the storage stage were investigated. The effect of the epoxy resin was studied in terms of the dispersion size of the emulsion, the mechanical properties, as well as the swell in water and toluene of the cast film, The emulsion was shown to be stable when the epoxy content was below 20% based on the mass of the polyacrylate in the system. The tensile strength and the modulus and the water and toluene resistance were enhanced with increase of the epoxy resin. In contrast, the elongation at break was decreased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 470–475, 2003
Modeling of the transient viscosity for polymer melts after startup of shearing and elongational deformations
Authors: Seo Yongsok 
Published: February 2003

AbstractIn order to describe the transient stress growth for polymer melts, the empirical model proposed by Seo for the viscosity of steady‐state flow is combined with a phenomenological viscoelastic model of a differential type (the White–Metzner model) along the lines proposed by Souvaliotis and Beris. The relaxation time is taken as a function of the invariant of the stress tensor (hence that of the configuration tensor) rather than that of the rate of the deformation tensor. Numerical results show a good correlation with experimental data. The model predictions approach steady‐state values at long times after the startup. The nonlinear form of the model correlates very well with the experimental data over many decades of the deformation rate, both in shearing and elongational deformations. The proposed model is a simple one that can also describe the overshoot in the transient stress growth. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 510–515, 2003
Preparation and anticoagulant property of phosphorylcholine‐terminated o‐benzoylchitosan derivative
Authors: Zhu Aiping , Zhang Jun , Shen Jian 
Published: February 2003

AbstractTo improve the solubility in organic solvent of chitosan, o‐benzoylchitosan was synthesized by acylation with benzoyl chloride and then used in the reaction with 2‐chloro‐1,3,2‐dioxaphosphospholane (COP) to prepare phosphorylcholine‐terminated o‐benzoylchitosan (PC‐BCS). PC‐BCS had a structure with a phospholipid polar group characterized by FTIR and 1H NMR. PC‐BCS had been polysubstituted by a PC group, which made PC‐BCS viscous liquid. The anticoagulant properties of PC‐BCS were evaluated by means of blood‐clotting and platelet adhesion assay. The blood‐clotting assay indicated that PC‐BCS could prolong the blood‐clotting process. Platelet adhesion assay showed that PC‐BCS could effectively inhibit the platelet adhesion and activation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 489–493, 2003
Modification of phenol–formaldehyde resol resins by lignin, starch, and urea
Authors: Turunen Marko , Alvila Leila , Pakkanen Tuula T. , Rainio Jouni 
Published: February 2003

AbstractLignin‐based chemicals, starch, and urea were used as modifiers for phenol–formaldehyde resol resins. The effects of the addition stage of the modifiers used in the synthesis of the resins and the type of modification reagent on the structures of the resins and their molar masses and reactivities were investigated. The modifications with corn starch and lignin promoted condensation; this was verified by increased molar masses and high ratios of methylene bridges to the sum of free ortho and para aromatic groups with respect to the corresponding reference resin without a modification reagent. The later the modifier was added to the resin condensation mixture, the more methylene bridges were formed with respect to the amounts of free ortho and para aromatic groups. In addition, when urea or wheat starch was added in the later condensation stage, the final condensation also reached high stages. The modifications with lignosulfonate and starch, as well as the early addition of urea, enhanced p–p′ bridge structures. The lowest condensation stage and, therefore, the highest reactivity were found when wheat starch was added with the starting reagents. The curing heat of the wheat‐starch‐modified resins decreased according to the deferred addition point of starch. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 582–588, 2003
Effect of stress state and polymer morphology on environmental stress cracking in polycarbonate
Authors: Raman Arun , Farris Richard J. , Lesser Alan J. 
Published: February 2003

AbstractEnvironmental stress crazing or cracking (ESC), a long studied phenomenon, is the brittle failure of glassy thermoplastics, which are normally ductile, under the synergistic action of stress and certain surface active agents. This work involves a study of a polycarbonate—oleic acid system under two novel in‐depth conditions: multiaxial stress states and changes in the polymer morphology. Initial uniaxial creep tests showed that the formation of cracks rather than crazes is observed. Multiaxial testing is done using blister tests where the polycarbonate film is stressed using a pressurizing medium to form a blister that is in a biaxial state of stress. Changes in the polymer morphology are induced by orientation of the polymer film. On samples exposed to stress and surface active agents, the stress component that is perpendicular to the direction in which the crazes/cracks form appears to influence the crack patterns. The polymer orientation has a significant influence. The orientation not only induces crack formation in a direction parallel to the orientation (regardless of the direction of the major principal stress), but it also reduces the stress required for crack formation for all stress states. Any attempt at modeling the phenomenon of environmental stress cracking therefore needs to take these effects into account. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 550–564, 2003
Polyelectrolyte complex formation between alginate and chitosan as a function of pH
Authors: Simsek‐Ege Fatma A. , Bond Gillian M. , Stringer John 
Published: February 2003

AbstractChitosan and alginate are two polyelectrolytes that can be used as thickening agents in the food industry, in drug‐release systems in pharmaceutical applications as biomaterials in wound healing, and cell culture applications, or as ion exchange material for the removal of heavy metal ions from industrial wastewaters. These two polysaccharides can also be used together to form a polyelectrolyte complex, especially to encapsulate proteins, cells, and enzymes. Although there are many applications of these polyions, few publications explain the interaction between their functional groups. This is mostly because of the difficulty of following ionic interaction in an interface of macromolecules, especially since they alter much with the reaction conditions such as pH. The present study reveals the interaction between chitosan and alginate at different pH values by means of a particular method for Fourier transform infrared (FTIR) studies. A previously reported disagreement between the yield of the complexes in weight and density of the interacting functional groups is explained through this method. The obtained results are supported with the morphological studies of the polyelectrolyte beads prepared at different pH values. Freeze‐dried beads of both alginate and chitosan‐coated alginate beads could be viewed after hexamethyl disilazane (HMDS) treatment. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 346–351, 2003
Complexation of uranyl ions by polypyrrole doped by sulfonated and phosphonated polyethyleneimine
Authors: Leroy D. , Martinot L. , Mignonsin P. , Strivay D. , Weber G. , Jérôme C. , Jérôme R. 
Published: February 2003

AbstractBranched polyethyleneimine (PEI) was sulfonated by reaction with chloropropanesulfonylchloride and phosphonated by reaction with phosphorous acid and formaldehyde. The accordingly formed polyanions were used as doping agents for polypyrrole (PPy). The amount of doping polyanions into thin films of PPy was measured by Rutherford back‐scattering. These films were tested for their capacity to extract uranyl ions from liquid wastes of low level activity. The uranium content was determined by neutron activation analysis, autoradiography, and gravimetry of uranium oxide after calcination. The resistance against static and dynamic leachings was also estimated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 352–359, 2003
Autoantibodies against B23, a nucleolar phosphoprotein, occur in scleroderma and are associated with pulmonary hypertension
Authors: Ulanet Danielle B. , Wigley Fredrick M. , Gelber Allan C. , Rosen Antony 
Published: February 2003

AbstractObjectiveTo determine whether the abundant nucleolar phosphoprotein B23 is a target of autoantibodies in scleroderma, and to examine the clinical phenotype associated with these antibodies.MethodsNinety‐two randomly selected scleroderma sera were screened by enzyme‐linked immunosorbent assay against recombinant human B23. Demographic, clinical, and serologic parameters associated with B23 autoantibody status were examined.ResultsWe demonstrated that autoantibodies against B23 occur in ∼11% of sera obtained from patients with scleroderma. B23 seropositivity was related to pulmonary hypertension, antifibrillarin antibody, anti‐RNP antibody, and decreased lung capacity. In multivariate analysis, B23 autoantibodies remained strongly associated with moderate‐to‐severe pulmonary hypertension and antifibrillarin antibodies.ConclusionThese data unite B23 with the group of nucleolar autoantigens targeted in scleroderma and thus focus attention on changes in the nucleolus that render its components immunogenic in this disease. The demonstration that antibodies to B23 are associated with an increased prevalence of pulmonary hypertension points to anti‐B23 antibodies as a possible marker of a specific phenotype in scleroderma.
Treatment of polyarteritis nodosa and microscopic polyangiitis with poor prognosis factors: A prospective trial comparing glucocorticoids and six or twelve cyclophosphamide pulses in sixty‐five patients
Authors: Guillevin Loïc , Cohen Pascal , Mahr Alfred , Arène Jean‐Pierre , Mouthon Luc , Puéchal Xavier , Pertuiset Edouard , Gilson Brigitte , Hamidou Mohamed , Lanoux Patricia , Bruet Alain , Ruivard Marc , Vanhille Philippe , Cordier Jean‐François 
Published: February 2003

AbstractObjectiveBecause the optimal cyclophosphamide (CY) treatment duration for severe polyarteritis nodosa (PAN) without virus infection and microscopic polyangiitis (MPA) has not been established, we conducted a trial to compare the effectiveness of 6 versus 12 CY pulses given in combination with corticosteroids (CS).MethodsSixty‐five (18 PAN, 47 MPA) previously untreated patients were randomized to receive 12 (n = 34) or 6 (n = 31) CY pulses combined with CS. PAN and MPA were histologically proven or met ACR criteria. All patients presented ≥1 factor of severity according to the five factor score (FFS). CY pulses were administered every 2 weeks for 1 month, then every 4 weeks. The end point of the study was the number of events (relapses and/or deaths) occurring in each group, analyzed according to an intention‐to‐treat strategy. The outcome was evaluated by Cox proportional hazards analysis.ResultsThe baseline characteristics were similar for both groups. The mean (± SD) followup was 32 ± 21 months. Survival analysis showed a significantly lower relapse probability (P = 0.02; hazards ratio [HR] = 0.34) and higher event‐free survival (P = 0.02, HR = 0.44) for the 12 CY‐pulse group while the mortality rates were not significantly different (P = 0.47).ConclusionThese results suggest that 6 CY pulses are less effective than 12 CY pulses to treat severe PAN and MPA, particularly with respect to the risk of relapses.
Use of the trust in physician scale in patients with rheumatic disease: Psychometric properties and correlates of trust in the rheumatologist
Authors: Freburger Janet K. , Callahan Leigh F. , Currey Shannon S. , Anderson Lynda A. 
Published: February 2003

AbstractObjectivesTo assess the psychometric properties of the Trust in Physician Scale and to identify variables associated with patients' trust in their rheumatologist.MethodsAnalyses of self reported data from 713 patients with rheumatoid arthritis, osteoarthritis, or fibromyalgia. Study variables included the Trust in Physician Scale, a decision‐making question, a medical skepticism measure, and demographic and health‐related measures. Internal consistency and construct validity were assessed using correlational analyses and factor analysis. A regression analysis was conducted to identify factors associated with trust in the rheumatologist.ResultsInternal consistency of the scale was high (Cronbach's alpha = 0.87). Scale items also loaded on a single factor. Construct validity was supported by inverse correlations between higher trust scores and both skepticism and independent decision making. Decreased trust was associated with older age, minority status, higher education, diagnosis of fibromyalgia or osteoarthritis, and poorer health.ConclusionThe Trust in Physician Scale is appropriate for patients with rheumatic disease. Several patient characteristics appear to be associated with lower trust in the rheumatologist.
Evidence for aerobic insufficiency in women with systemic lupus erythematosus
Authors: Keyser Randall E. , Rus Violeta , Cade William Todd , Kalappa Neeta , Flores Raymond H. , Handwerger Barry S. 
Published: February 2003

AbstractObjectiveTo determine if fatigue is associated with diminished aerobic capacity in women with systemic lupus erythematosus (SLE).MethodsEighteen women (age 35 ± 9 years) with mild SLE (Systemic Lupus Activity Measure = 3.1 ± 2.1) and 16 healthy but sedentary controls (age 38 ± 8 years) completed peak treadmill exercise tests to determine aerobic capacity and Fatigue Severity Scales to quantify the severity of fatigue. Measures of oxygen consumption (VO2) were recorded during the treadmill tests.ResultsPeak VO2 was lower in patients with SLE (19.2 ± 4.4 ml/kg/minute) as compared with controls (27.4 ± 4.7 ml/kg/minute) and expected values (30.7 ± 3.1 ml/kg/minute; P < 0.0006 versus controls and P < 0.0001 versus expected). Functional aerobic impairment was observed in 14 of the 18 patients with SLE. In patients with SLE, ventilatory threshold, a marker for the onset of lactic acidemia, was observed at the lowest energy requirement for instrumental activities of daily living. Peak VO2 in the patients with SLE was similar to the highest energy requirements for instrumental activities of daily living, leaving little or no reserve for more intense occupational and recreational activities. Peak VO2 was significantly higher (P < 0.0001) than the activity of daily living requirements in controls, providing a substantial energy reserve. Fatigue severity score (FSS) was 5.0 ± 1.4 in patients with SLE, with 14 of the 18 patients having scores above 4.0, a score indicating that fatigue severity limited physical activity. Of the 14, 12 had functional aerobic impairment. An FSS of greater than 4.0 was not observed in controls (mean = 2.5 ± 0.7).ConclusionIn women with SLE, aerobic capacity was diminished to levels that were insufficient for engaging in activities of daily living and below those expected to result from physiologic deconditioning. This functional aerobic impairment was strongly correlated with the perception of severe, activity‐limiting fatigue.