bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrical and mechanical behaviors of carbon nanotube‐filled polymer blends
Authors: Wu Man , Shaw Leon 
Published: October 2005

AbstractFour carbon nanotube (CNT)‐filled polymer blends, i.e., CNT‐filled polyethylene terephthalate (PET)/polyvinylidene fluoride, PET/nylon 6,6, PET/polypropylene, and PET/high‐density polyethylene blends, have been injection‐molded and characterized in terms of their microstructures, electrical conductivities, and mechanical properties. The distribution of CNTs in the polymer blends has been examined based on their wetting coefficients and minimization of the interfacial energy. The electrical conductivity and mechanical properties have been related to the cocontinuous polymer blends, the conductive path formed by CNTs, the CNT distribution, and the intrinsic properties of the constituent polymers. It is found that to obtain a CNT‐filled polymer composite with both high electrical conductivity and good mechanical properties, it is preferred that most CNTs distribute in one polymer phase, while the other polymer phase(s) remain neat. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 477–488, 2006
Structure‐property relations in UV‐curable urethane acrylate oligomers
Authors: Khudyakov Igor V. , Swiderski Kenneth W. , Greer Robert W. 
Published: October 2005

AbstractFour urethane acrylate oligomers were synthesized by a reaction of an excess of isophorone diisocyanate (D) with polypropylene glycol Acclaim 4200N (P) with a subsequent reaction of nonreacted D with a hydroxy acrylate Tone M100 (A). The latter has a common name caprolactone acrylate. Oligomers were prepared by different ways of addition of P to D or D to P and at different ratio of [D]/[P]. The fifth oligomer ADA was prepared as an individual compound. Viscosities, GPC traces, Tg's of oligomers were taken alongside with other physical properties of cured oligomers. It was demonstrated that oligomers with P consist of ADPDA, ADA, and of a chain‐extended product A… Pn… A, which has two or more Ps in a molecule. Additive contributions of these three components essentially determine properties of the liquid and cured oligomers. Structure‐property relations of urethane acrylate oligomers are discussed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:489–494, 2006
New fluorescent monomers and polymers displaying an intramolecular proton‐transfer mechanism in the electronically excited state. III. Thermogravimetric stability study of the benzazolylvinylene derivatives
Authors: Campo Leandra Franciscato , Rodembusch Fabiano Severo , Stefani Valter 
Published: October 2005

AbstractSix fluorescent benzazolylvinylene derivatives were studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and related molecular parameters. The thermal stability was determined in terms of the steps of degradation and its fitting parameters, such as maximum degradation rate (Rmax), maximum degradation rate temperature (TRmax), degradation temperature range, which is related to the half‐width at half‐height values (Γ), and the kinetic parameters: activation energy (Ea), pre‐exponential factor (A), and reaction order (n) obtained by Barrett's method. Different organic substitutes and heteroatoms do not play a fundamental role in the thermal behavior of the studied dyes. The compensation effect between pre‐exponential factor and activation energy was confirmed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 495–500, 2006
Abs/iron nanocomposites prepared by cryomilling
Authors: Zhu Y. G. , Li Z. Q. , Zhang D. , Tanimoto T. 
Published: October 2005

AbstractAcrylonitrile‐Butadiene‐Styrene (ABS)/iron nanocomposites have been prepared by cryomilling (high‐energy ball milling under cryogenic temperature), and a microstructure of iron network in ABS matrix was obtained. The blending scale and homogenization of ABS/iron nanocomposites are observed by Atomic Force Microscope (AFM). The morphology and structure of cryomilled composite powders are characterized by means of Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), and X‐ray Diffraction (XRD). The results indicate that upon cryomilling for 20 h, ABS and Fe are intimately blended with the single composite particle size less than 100 nm, the Fe phase domains less than 50 nm, and Fe grain size reduced to 20 nm. Both the fast rate of homogenization and size reduction are mainly attributed to the introduction of cryogenic temperature and comilling. The evidences suggest that cryomilling is a capable and promising technique for the production of polymer/metal nanocomposites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 501–505, 2006
Interpolymer complex microparticles based on polymethacrylic acid‐chitosan for oral insulin delivery
Authors: S. Sajeesh , Sharma Chandra P. 
Published: October 2005

AbstractIn the present study, microparticles composed of polymethacrylic acid‐chitosan (PMAA‐CS) were prepared by a novel interionic gelation method. Free‐radical polymerization of methacrylic acid was carried out in the presence of CS, using a water‐soluble initiator, and application of these microparticles toward oral insulin delivery was evaluated. Microparticles obtained were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) studies. From SEM studies, it was observed that microparticles had an aggregated morphology with size ∼20 μm, while FTIR confirmed the presence of ionic interaction between PMAA and CS chains. Protein loading was done by diffusion filling method, and from in vitro release study, it was observed that insulin‐loaded microparticles displayed a pH depended release profile at alkaline/acidic pH. Microparticles exhibited sustained release of insulin for 3–4 h at neutral pH, and enzyme linked immunosorbent assay (ELISA) proved that encapsulated protein maintained 100% biological activity at neutral pH. Preliminary study suggests that these microparticles can serve as good candidate for oral protein delivery. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 506–512, 2006
Effect of heat‐sealing temperature on the properties of OPP/CPP heat seals. Part II. Crystallinity and thermomechanical properties
Authors: Tetsuya Tsujii , Hashimoto Yasuo , Ishiaku U. S. , Mizoguchi M. , Leong Y. W. , Hamada Hiroyuki 
Published: October 2005

AbstractThe crystalline structure of the heat‐sealed part of oriented polypropylene (OPP) and cast polypropylene (CPP) films was investigated by differential scanning calorimetry, Fourier transform infrared spectroscopy, and thermal mechanical analysis (TMA). The relationship between the crystalline structure and the mechanical properties was analyzed. It was found that the high total crystallinity of both OPP and CPP gave rise to good mechanical properties and that the orientation of the crystalline structure in the OPP film also was an important factor. The optimum condition for heat sealing was the temperature at which total crystallinity was highest while still retaining the crystalline orientation of OPP. The assessment of crystalline orientation by TMA is an innovation initiated by the authors. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 513–519, 2006
Silicon‐29 and carbon‐13 nuclear magnetic resonance identification of intermediates developed during the formation of a hybrid based on tetraethoxysilane (TEOS) and 4‐[(5‐dichloromethyl)(silyl)pentyloxy]cyanobenzene (DCN)
Authors: Trejo‐Duran Mónica , Martínez‐Richa Antonio , Vera‐Graziano Ricardo , Mendoza‐Diaz Guillermo , Castaño‐Meneses Victor M. 
Published: October 2005

AbstractDuring the formation of organic–inorganic hybrid materials by the sol–gel process, the observation of multiphase systems at different stages of the reaction is not uncommon. An assessment of the chemical species formed before and after gelation is not an easy task because complex mixtures are generally found in these systems. In this study, the identification of intermediates developed during the formation of a hybrid obtained from tetraethoxysilane (TEOS) and 4‐[(5‐dichloromethylsilyl)pentyloxy]cyanobenzene monomer has been undertaken. Solution and solid‐state29Si‐ and13C‐NMR spectra, recorded at different degrees of conversion, allow the elucidation of the mechanism of hybrid formation. 4‐[(5‐dichloromethylsilyl)pentyloxy]cyanobenzene, (DCN), DCN–TEOS cyclosiloxanes and low‐molecular‐weight linear copolysiloxanes are formed in the early stages of the process and before gelation occur. Before the gel is formed, cyclic species undergo an acid‐catalyzed ring‐opening copolymerization with silica to produce a random copolymer. Other intermediates of the Qijtype (where Q indicates a four‐functional silicon, the first subscript indicates the number of siloxane bridges connected to the silicon site, and the second subscript indicates the number of silanol groups) that develop before the gel is formed have also been identified. Spectral peak patterns of the final hybrid, observed in solid‐state29Si and13C‐NMR spectra, are also discussed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 520–531, 2006
Effect of an epoxy‐based bonding agent on the cure characteristics and mechanical properties of short‐nylon‐fiber‐reinforced acrylonitrile–butadiene rubber composites
Authors: Seema A. , Kutty S. K. N. 
Published: October 2005

AbstractThe cure characteristics and mechanical properties of short‐nylon‐fiber‐reinforced acrylonitrile–butadiene rubber composites with and without an epoxy resin as a bonding agent were studied. The epoxy resin was a good interfacial‐bonding agent for this composite system. The minimum torque showed a marginal increase with the resin concentration. The maximum–minimum torque showed only a marginal change with the resin. The scorch time decreased with the fiber concentration and resin content. The tensile strength and abrasion resistance were improved and the tear resistance and resilience were reduced with the resin concentration. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 532–539, 2006
Viscosity of polystyrene solutions expanded with carbon dioxide
Authors: Whittier Rachel E. , Xu Dawei , van Zanten John H. , Kiserow Douglas J. , Roberts George W. 
Published: October 2005

AbstractThe viscosity of solutions of polystyrene (PS) in decahydronaphthalene (DHN) was measured in the presence of carbon dioxide (CO2) with a moving‐piston viscometer. The effects of the CO2 pressure (0–21 MPa), polymer concentration (1–15 wt %), temperature (306–423 K), and polymer molecular weight (126 and 412 kDa) on the viscosity were investigated. In the absence of CO2, the increase in the viscosity with increasing polymer concentration was approximately exponential in concentration and was well described by the Martin equation. All the data fell on a single line when the relative viscosity was plotted against cM0.50 (where c is the concentration of the polymer in solution and M is the molecular weight of the polymer). The viscosity of the polymer solution decreased with increasing CO2 pressure under otherwise constant conditions. For a given CO2 pressure, the viscosity reduction was greatest when the relative viscosity was high in the absence of CO2, that is, for high‐molecular‐weight polymer, high polymer concentrations, and low temperatures. Reductions in the relative viscosity of almost 2 orders of magnitude were observed in some cases. The viscosity of solutions of PS in DHN also was measured in the presence of sulfur hexafluoride (SF6). At a given pressure, SF6 was about as effective as CO2 in reducing the solution viscosity. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 540–549, 2006
DSC study of the cure kinetics during nanocomposite formation: Epoxy/poly(oxypropylene) diamine/organically modified montmorillonite system
Authors: Ivankovic Marica , Brnardic Ivan , Ivankovic Hrvoje , Mencer Helena Jasna 
Published: October 2005

AbstractThe effect of an organically modified montmorillonite (OMMT) on the curing kinetics of a thermoset system based on a bisphenol A epoxy resin and a poly(oxypropylene)diamine curing agent were studied by means of differential scanning calorimetry (DSC) in isothermal and dynamic (constant heating rate) conditions. Montmorillonite and prepared composites were characterized by X‐ray diffraction analysis (XRD) and simultaneous differential scanning calorimetry–thermogravimetric analysis (DSC–TGA). Analysis of DSC data indicated that the presence of the filler has a very small effect on the kinetics of cure. A kinetic model, arising from an autocatalyzed reaction mechanism, was applied to the DSC data. Fairly good agreement between experimental and modeling data was obtained. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 550–557, 2006
Synthesis and characterization of fluoropolymer modified polyacrylate in emulsion polymerization
Authors: Chen Zhengxia , Cui Xuejun , Jiang Wenyong , Cheng Xiuli , Wang Hongyan 
Published: October 2005

AbstractA novel method to produce fluorine‐containing polyacrylate emulsion is presented. It is prepared by the copolymerization of n‐methyl methacrylate, n‐styrene, n‐butyl acrylate, and α‐methacrylic acid in the presence of swollen particles of PTFE. The structure and properties of the polymers are characterized by GPC, PSD, SEM, and XPS. The number‐average molar mass (Mn) 51,332, and the polydispersity 5.8688 are obtained. The mean diameter of latex particles is 300nm. Scanning electron microscopy reveals that particles of the emulsion are well dispersed. Meanwhile, the F1S content of the surface on the latex membrane is 8.99%. It is shown that the method of mixing micron and nanometer‐sized particles should be made the next step of research. It is also proved that inertia polymers can be used in emulsion property modification. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 558–562, 2006
Optical monitoring of polyesters injection molding
Authors: Marinelli Alessandra Lucas , Farah Marcelo , Elida Rosario , Bretas Suman 
Published: October 2005

AbstractAn optical fiber sensor similar to the one developed by Thomas and Bur1 was constructed for the monitoring of the crystallization of three polyesters during the injection molding process. The polyesters studied were: polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), and polyethylene terephthalate (PET). With this optical system it was possible to obtain, in real time, some essential parameters of the polyester crystallization kinetics at different processing conditions. Thus, a study of the influence of injection molding variables on the nonisothermal crystallization kinetics of these polyesters was done. The processing variables were: mold wall and injection temperatures, Tw and Ti, respectively; flow rate, Q; and holding pressure, Ph. The experiments were done following a first order central composite design statistical analysis. The morphology of the samples was analyzed by polarized light optical microscopy, PLOM. The signal of the laser beam during the filling and the crystallization stages of the injection molding of these materials was found to be reproducible. The measurements showed that this system was sensitive to variations of the crystallization of different types of polymers under different processing conditions. The system was not able, however, to monitor the crystallization process when the crystallinity degree developed by the sample was very low, as in the PET resin. It was also observed that Tw and Ti were the most influential variables on the crystallization kinetics of PBT and PTT. Due to its slower crystallization kinetics, PTT was found to be more sensitive to changes in these parameters than the PBT. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 563–579, 2006
Effects of composition of hardener on the curing and aging for an epoxy resin system
Authors: Wu Lixin , Hoa Suong V. , Minh‐Tan  , Ton‐That  
Published: October 2005

AbstractDifferent mixture ratios of Shell Epon 828 (based on diglycidyl ether of bisphenol A, DGEBA) and Shell EPI‐CURE 3046 (based on triethylenetetramine, TETA) were evaluated under different environments of isothermal curing at 80°C in DSC, room temperature curing in air, and aging in water at 45°C. The curing reactions were monitored using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and infrared spectroscopy (IR). It was shown that the initial curing rate increased with the amount of hardener. However, the epoxy groups in samples with excess hardener were prone to reaction with primary amines located at the ends of TETA molecules, resulting in a less dense epoxy network. During aging in water at 45°C, significant effects of water on the postcure and the increased water absorption with an increase of hardener amount were observed. The DMA results show that the samples with hardener around stoichiometric composition have the greatest storage modulus while curing in air environment. However, the samples with hardener much less than stoichiometric composition have greater storage modulus under aging in water at 45°C. in water at 45°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 580–588, 2006
Momentary relationship between cortisol secretion and symptoms in patients with fibromyalgia
Authors: McLean Samuel A. , Williams David A. , Harris Richard E. , Kop Willem J. , Groner Kimberly H. , Ambrose Kirsten , Lyden Angela K. , Gracely Richard H. , Crofford Leslie J. , Geisser Michael E. , Sen Ananda , Biswas Pinaki , Clauw Daniel J. 
Published: October 2005

AbstractObjectiveTo compare the momentary association between salivary cortisol levels and pain, fatigue, and stress symptoms in patients with fibromyalgia (FM), and to compare diurnal cycles of cortisol secretion in patients with FM and healthy control subjects in a naturalistic environment.MethodsTwenty‐eight patients with FM and 27 healthy control subjects completed assessments on salivary cortisol levels and pain, fatigue, and stress symptoms, 5 times a day for 2 consecutive days, while engaging in usual daily activities. Only those participants who adhered to the protocol (assessed via activity monitor) were included in the final analyses.ResultsTwenty FM patients and 16 healthy control subjects adhered to the protocol. There were no significant differences in cortisol levels or diurnal cortisol variation between FM patients and healthy controls. Among women with FM, a strong relationship between cortisol level and current pain symptoms was observed at the waking time point (t = 3.35, P = 0.008) and 1 hour after waking (t = 2.97, P = 0.011), but not at the later 3 time points. This association was not due to differences in age, number of symptoms of depression, or self‐reported history of physical or sexual abuse. Cortisol levels alone explained 38% and 14% of the variation in pain at the waking and 1 hour time points, respectively. No relationship was observed between cortisol level and fatigue or stress symptoms at any of the 5 time points.ConclusionAmong women with FM, pain symptoms early in the day are associated with variations in function of the hypothalamic–pituitary–adrenal axis.
The lateral view radiograph for assessment of the tibiofemoral joint space in knee osteoarthritis: Its reliability, sensitivity to change, and longitudinal validity
Authors: LaValley Michael P. , McLaughlin Sara , Goggins Joyce , Gale Daniel , Nevitt Michael C. , Felson David T. 
Published: October 2005

AbstractObjectiveTo evaluate the reliability, validity, and sensitivity to change of tibiofemoral (TF) narrowing on lateral radiographic views.MethodsIn a natural history study of symptomatic knee osteoarthritis (OA), both lateral view and fluoroscopically positioned posteroanterior (PA) semiflexed view radiographs of the knee in 30° of flexion and with weight bearing were obtained at baseline and at 30 months. Test–retest reliability was evaluated using repeat radiographs, with joint space width measured using electronic calipers. All radiographs were scored on a 0–3 scale, and progression of joint space loss was defined as narrowing of the joint space by 1 grade. We evaluated sensitivity to change compared with the PA view. We evaluated validity by examining whether knees with progression showed expected malalignment on full‐limb films.ResultsTest–retest reliability of the TF joint space using the lateral view had a root mean square error of 0.303 mm, with 92.5% of repeats within 1 mm. More knees showed progression on the lateral view alone (n = 41) than on the PA view alone (n = 27). Compared with knees without joint space loss, knees with medial compartment loss on the lateral view only were more varus malaligned (P < 0.001), while those with lateral compartment loss were more valgus malaligned (P = 0.008).ConclusionIn the assessment of TF joint space loss, lateral view radiographs are reliable, valid, and more sensitive to change than fluoroscopically positioned PA radiographs.
Does hand osteoarthritis predict future hip or knee osteoarthritis?
Authors: Dahaghin S. , Bierma‐Zeinstra S. M. A. , Reijman M. , Pols H. A. P. , Hazes J. M. W. , Koes B. W. 
Published: October 2005

AbstractObjectiveTo evaluate the risk of future hip or knee osteoarthritis (OA) in subjects with hand OA at baseline and to evaluate whether the concurrent presence of hand OA, other risk factors for OA, or an OA biomarker (type II collagen C‐telopeptide degradation product [CTX‐II]) further increases the risk.MethodsRadiographs of the hands (baseline) and the hips and knees (baseline and 6.6 years later) were obtained in a randomly selected subset of participants in the Rotterdam Study who were ages 55 years and older. Radiographs were scored for the presence of OA using the Kellgren/Lawrence (K/L) system. A total of 1,235 subjects without OA of the hip/knee (K/L score 0–1) at baseline were included in the study. CTX‐II levels were measured at baseline. The independent risk of future hip/knee OA in subjects with hand OA at baseline was assessed by logistic regression, as stratified for age, sex, body mass index, family history of OA, and heavy workload.ResultsOverall 12.1% of the participants (19.7% of those with hand OA versus 10.0% of those without) developed hip or knee OA (odds ratio [OR] 2.1 [95% confidence interval (95% CI) 1.3–3.1]). Subjects with hand OA had an increased risk of future hip OA (OR 3.0 [95% CI 1.6–5.4]), which was further increased in those with a family history of OA. Subjects with hand OA had an OR of 1.6 [95% CI 1.0–2.8) for the future development of knee OA, which was further increased in those who were overweight. Concurrent hand OA and high levels of CTX‐II further increased the risk of having hip or knee OA at followup (OR 4.2 [95% CI 2.3–7.8]).ConclusionThe presence of hand OA at baseline showed an increased risk of future hip/knee OA (higher for hip OA than for knee OA). The concurrent presence of hand OA and other OA risk factors or high CTX‐II levels further increased the risk of future hip/knee OA.