bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wlds mice are resistant to paclitaxel (taxol) neuropathy
Authors: Wang Min Sheng , Davis Albert A. , Culver Deborah G. , Glass Jonathan D. 
Published: October 2002

AbstractThe WldS mouse is a unique mutant strain that demonstrates the remarkable phenotype of prolonged survival of transected axons (“slow Wallerian degeneration”). In these studies, we tested whether this neuroprotective phenotype extends to axonal degeneration seen in a progressive peripheral neuropathy. WldS and wild‐type mice were intoxicated with the cancer chemotherapeutic agent paclitaxel (Taxol). The severity of the resultant sensory neuropathy was compared with behavioral, physiological, and pathological measures. WldS mice were resistant to paclitaxel neuropathy by all measures, and the resistance was because of protection against axonal degeneration. These studies demonstrate for the first time that the WldS mouse is more than a slow Wallerian degeneration phenotype, emphasizing the mechanistic link between Wallerian degeneration and peripheral neuropathy. Understanding how this mutant gene confers protection against axonal degeneration will provide important clues toward prevention of axonal degeneration in several human neurological disorders.
Water‐uptake kinetics in poly(methyl methacrylate) films with a fluorescent rotor probe
Authors: Goodelle J. P. , Pearson R. A. , Santore M. M. 
Published: October 2002

AbstractA fluorescence method was adapted to measure moisture‐uptake kinetics in films of poly(methyl methacrylate), and data were interpreted in the context of a Fickian diffusion model. The films, 2–60 μm thick, were supported on acid‐etched microscope slides. They were compared with several freestanding slabs about 1 mm thick. The moisture diffusion in the slabs was Fickian with a diffusivity of 3.2 × 10−9 cm2/s. The apparent Fickian diffusivity in the films decreased substantially with decreasing film thickness; however, a careful examination revealed that the initial moisture uptake was governed by a thickness‐independent diffusivity for a wide range of film thicknesses. This suggested that the appearance of non‐Fickian behavior originated within about a micrometer of the buried interface, possibly as a result of water accumulation beneath the film or slight thickness variations. Moisture uptake in the thickest films was more rapid than in the slabs, most likely because of residual thermal stresses. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2463–2471, 2002
The effect of structural features on mechanical properties of loose optical fiber poly(butylene terephthalate) tubes
Authors: Ambroziak Mariusz , Gruin Irma , Wronikowski Marian , Zdunek Krzysztof 
Published: October 2002

AbstractResults of a study on the modifying mechanical properties of loose optical‐fiber poly(butylene terephthalate) (PBT) tubes, produced during the standard industrial extrusion process, show that heat treatment make the structure of their material to change. The study comprised measurements of mechanical strengths properties of the tubes (tensile strength, compression strength, kinking) and determination of tube material structure [by differential thermal analysis (DTA), wide angle X‐ray scattering analysis (WAXD), and scanning electron microscopy (SEM)]. Results of the study allowed observation that the annealing at 70°C for 34 h of the tubes caused the crystalline α phase to increase in the tube material from ∼28.5% to ∼31.5% and the structure of the existing crystallites to become more perfect. This made the values of certain mechanical properties of the tubes to increase even by as much as 30%. The tubes following such thermal treatment could be used in cables exposed to heavy‐duty operation in arduous environments, where a larger margin from the standpoint of mechanical properties is required. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2130–2134, 2002
Degradation of low density polyethylene during extrusion. I. Volatile compounds in smoke from extruded films
Authors: Andersson Thorbjörn , Wesslén Bengt , Sandström John 
Published: October 2002

AbstractMany problems with odor and taste in food packaging can be traced to degradation of the packaging materials during processing. From this starting point, the degradation of polyethylene in a commercial extrusion coating process was studied by analyzing degradation products present in smoke sampled at the extruder die orifice. Two low‐density polyethylenes, A and B, with similar melt flow indexes and densities and obtained from different producers, were investigated. A third polymer, C, consisting of recycled material B, was also investigated. More than 40 aliphatic aldehydes and ketones, together with 14 different carboxylic acids, were identified in the smoke. The highest concentration was found for acetaldehyde, regardless of polymer and processing conditions. Increasing the extrusion temperatures in the range 280–325 °C increased the amounts of the oxidized products in the smoke. The extruded film thickness, 12 and 25 μm, influenced the concentrations of degradation products, with the thicker film giving higher amounts of product. The recycled polymer C generally gave lower concentrations of degradation products compared with the virgin polymer B. Differences in the product spectrum between the two virgin polymers may be related to differences in the manufacturing process. Many of the identified compounds have very characteristic taste and smell and are consequently of interest from an odor and taste point of view in food packaging applications. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1580–1586, 2002
Mechanical properties of conducting H‐type polysiloxane–polypyrrole graft copolymers and polytetrahydrofuran–polypyrrole block copolymers
Authors: Biran C. , Toppare L. , Tinçer T. , Yağci Y. , Harabagiu V. 
Published: October 2002

AbstractThe mechanical properties of block copolymers of polypyrrole and pyrrolyl‐ended azobis‐polytetrahydrofuran (TPPy) and graft copolymers of pyrrolyl‐ended H‐type polydimethylsiloxane (SPPy) were investigated and compared with those of polypyrrole (PPy). Conducting films were prepared electrochemically at a constant potential and doped with p‐toluene sulfonate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1663–1666, 2002
Synthesis and characterization of degradable copoly(ester–amide)s: Poly(trans‐4‐hydroxy‐L‐proline‐co‐ε‐caprolactam)
Authors: Lee Ren‐Shen , Yang Jen‐Ming 
Published: October 2002

AbstractNovel copolyesteramides were synthesized by reacting trans‐4‐hydroxy‐N‐benzyloxycarbonyl‐L‐proline (N‐CBz‐Hpr) with ε‐caprolactam (CLM) in the presence of stannous octoate [Sn(II) Oct.] as a catalyst. Various techniques, including 1H‐NMR, IR, DSC, and viscosity, were used to elucidate structural characteristics and thermal properties of the resulting copolymers. Data showed that the optimal reaction condition for the synthesis of the copolymers was obtained by using 3 wt % Sn(II) Oct. at 170°C for 24 h. The DSC analysis demonstrated amorphous structure for most of the copolymers. The glass‐transition temperature of the copolymers shifts to a higher temperature with increasing Hpr/CLM molar ratio. In vitro degradation of these poly(N‐CBz‐Hpr‐co‐CLM)s was evaluated by weight loss measurements. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1615–1621, 2002
Synthesis, degradation, and drug delivery of cycloaliphatic poly(ester anhydride)s
Authors: Zhang Tao , Xu Min , Chen Hong , Yu Xuehai 
Published: October 2002

AbstractThe high melting point of poly(1,4‐cyclohexanedicarboxylic anhydride) [poly(CHDA)] is a disadvantage, in that it is intractable in the melting process of a drug delivery system. This report relates to diols introduced into the polyanhydride main chain to decrease its melting point. Various poly(ester anhydride)s containing ethylene glycol, 1,3‐propanediol, 1,4‐butanediol, or 1,6‐hexandiol [poly(CHDA–XDO)] were synthesized by the esterification reaction and melt polycondensation. FTIR, DSC, WAXD, and intrinsic viscosity of polymers were recorded and hydrolytic degradation, as well as in vitro drug delivery, was conducted. The results show that the samples are stable in an anhydrous environment at room temperature and degrade in water following a surface erosion mechanism. The degradation period of poly(CHDA–XDO) ranged from 130 to 320 h as a result of the different diols and amounts of XDO introduced. The in vitro drug delivery gave 130–350 h of stable delivery along with the typical surface erosion mechanism. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2509–2514, 2002
Synthesis and characterization of the copolymer of dodecyl methacrylate/styrene containing an amidine functional group
Authors: Erhan Sevim Z. , Sheng Quan , Adhvaryu Atanu 
Published: October 2002

AbstractA copolymer of dodecyl methacrylate/styrene (DMA/St) containing the amidine functionality was synthesized and characterized. The one‐step solution copolymerization process was carried out using a mixed solvent, high temperature, and a functional azo initiator, 2,2′‐azobis[N,N′‐dimethylene isobutyramidine]. Copolymers with different compositions (DMA/St 10/1 to 1/2), molecular weight (Mn 2000–9000), and functionality (1.0–2.0) were prepared and characterized by NMR, FTIR, DSC, and elemental analysis. The molecular weight of the copolymers could be controlled by the amount of the initiators. Copolymer composition depends on the feed molar ratio of comonomers. The amidine functionality of the copolymers was determined by elemental analysis. It was found that 72% of the polymer chain has one functionality. The Tg of the copolymer depends on the feed molar ratio. This copolymer could be used as a potential dispersant for lubricant oil. Published 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1684–1691, 2002
On the development of natural fiber composites of high‐temperature thermoplastic polymers
Authors: Jana Sadhan C. , Prieto Alberto 
Published: October 2002

AbstractA new method is presented for the development of natural fiber composites of high‐performance thermoplastic polymers considering poly(phenylene ether) (PPE) and wood flour as an example system. The large gap between the high processing temperature of PPE, typically between 280 and 320°C, and the low decomposition temperature of wood flour, about 200°C, was reduced by using a reactive solvent, a low molecular weight epoxy. The epoxy formed miscible blends with PPE, which offered much lower viscosity compared to PPE and processing temperatures well below the decomposition temperature of wood flour. In addition, the epoxy component accumulated around the polar wood flour particles upon polymerization during the fabrication step. The composite materials consisted of a thermoplastic continuous phase and two dispersed phases, one of polymerized epoxy and the other of wood flour particles coated with polymerized epoxy. These composites offered a significant reduction in density and better mechanical and physical properties when compared to commercially available grades of engineering polymer blends filled with short glass fibers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2159–2167, 2002
Synthesis and characterization of side‐chain liquid‐crystalline polyacrylates containing azobenzene moieties
Authors: Silong S. , Lutfor M. R. , Ab Rahman M. Z. , Wan Yunus W. M. Z. , Haron M. J. , Ahmad M. B. , Wan Yusoff W. M. D. 
Published: October 2002

AbstractSyntheses of novel liquid‐crystalline polymers containing azobenzene moieties were performed by a convenient route with an acrylate backbone. The azobenzenes were key intermediates of the monomers, and side‐chain liquid‐crystalline polymers were prepared, that is, poly[α‐{4‐[(4‐acetylphenyl)azo]phenoxy}alkyloxy]acrylates, for which the spacer length was 3 or 11 methylene units. In addition, poly[3‐{4‐[(3,5‐dimethylphenyl)azo]phenoxy}propyloxy]acrylate was prepared with a spacer length of 3 methylene units. The structures of the precursors, monomers, and polymers were characterized with Fourier transform infrared, 1H‐NMR, and 13C‐NMR techniques. The polymers were obtained by conventional free‐radical polymerization with 2,2′‐azobisisobutyronitrile as an initiator. The phase‐transition temperatures of the polymers were studied with differential scanning calorimetry, and the phase structures were evaluated with a polarizing optical microscopy technique. The results showed that two of the monomers and their corresponding polymers exhibited nematic liquid‐crystalline behavior, and one of the monomers and its corresponding polymer showed smectic liquid‐crystalline behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2653–2661, 2002
Modification of epoxy resin with optically active carboxylic acid
Authors: Samui A. B. , Ratna D. , Chavan J. G. , Deb P. C. 
Published: October 2002

AbstractL‐leucine was converted to S‐2‐chloro, 4‐methyl pentanoic acid (CMPA) with retention of optical activity. CMPA was reacted with the epoxy resin to form chiral monoester and chiral diester compounds. The modified epoxy resin (MER) was characterized by FTIR spectrophotometer and polarimeter and was analyzed for epoxy content. The MER shows optical activity and the optical rotation increases with increasing concentration of CMPA. DSC studies indicate similar reactivity of the enantiomers of CMPA as well as the recemic mixture. The MER containing different concentrations of chiral modifier was cured with a stoichiometric amount of amine hardener. The cured film (obtained up to 21 mol % of CMPA) exhibits chiral property as well. Dynamic mechanical thermal analysis (DMTA) studies indicate high damping behavior. A shift in tan δ peak toward lower temperature was observed with increasing concentration of chiral modifier. The tan δmax increases up to 14 mol % of CMPA in MER and decreases thereafter. However, storage modulus gradually decreases with an increase in CMPA. Cured film based on two enantiomer‐modified epoxy samples shows different damping behavior. CMPA was also blended with poly(methyl methacrylate) and the blend films were studied similarly. The system behaves in a similar fashion as observed with cured MER films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2523–2529, 2002
On the compatibility of polysaccharide/maleic copolymer blends. II. Thermal behavior of pullulan‐containing blends
Authors: Bumbu Gina‐Gabriela , Vasile Cornelia , Chiţanu Gabrielle Charlotte , Carpov Adrian 
Published: October 2002

AbstractThe compatibility of pullulan with maleic acid/vinyl acetate copolymers in the solid state in the form of thin films was studied with thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and optical microscopy. With respect to morphology, blends with a content of pullulan greater than 85 wt % exhibited an even distribution of finely dispersed particles. The thermal properties were dependent on the mixing ratio, and the interactions between components were quite pronounced in the pullulan‐rich blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1782–1791, 2002
Synthesis and properties of polyether with short alternating conjugated and nonconjugated blocks containing oxadiazole units
Authors: Meng Fanbao , Zhang Baoyan , Zhi Junge , Guan Yan , Jia Yinggang 
Published: October 2002

AbstractA polyether, poly[(2,5‐dimethylene‐1,3,4‐oxadiazole)dioxy‐1,4‐phenylene‐1,2‐ethenylene‐1,4‐phenylene‐1,2‐ethenylene‐1,4‐phenylene], based on short alternating conjugated oxadiazole units, has been synthesized, which is a kind of PPV derivative that emits blue light. The resulting polymer is fairly soluble in chloroform. The synthesized polymer shows a UV–visible absorbency maximum wavelength around 310 nm in solution. The photoluminescence maximum wavelength for the resulting polymer appears around 470 nm. The polymer also exhibits good thermal stability up to 300°C under N2 atmosphere. It is also observed that the onset temperature of thermal decomposition is as high as 355°C. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2682–2686, 2002
Mechanical properties of films prepared from model high‐glass‐transition‐temperature/low‐glass‐transition‐temperature latex blends
Authors: Tang Jiansheng , Daniels Eric S. , Dimonie Victoria L. , Vratsanos Menas S. , Klein Andrew , El‐Aasser Mohamed S. 
Published: October 2002

AbstractThe mechanical properties of films prepared from model high‐glass‐transition‐temperature (Tg)/low‐Tg latex blends were investigated with tensile testing and dynamic mechanical analysis. Polystyrene (PS; carboxylated and noncarboxylated) and poly(n‐butyl methacrylate‐co‐n‐butyl acrylate) [P(BMA/BA); noncarboxylated] were used as the model high‐Tg and low‐Tg latexes, respectively. Carboxyl groups were incorporated into the PS latex particles to alter their surface properties. It was found that the presence of carboxyl groups on the high‐Tg latex particles enhanced the Young's moduli and the yield strength of the PS/P(BMA/BA) latex blend films but did not influence ultimate properties, such as the stress at break and maximum elongation. These phenomena could be explained by the maximum packing density of the PS latex particles, the particle–particle interfacial adhesion, and the formation of a “glassy” interphase. The dynamic mechanical properties of the latex blend films were also investigated in terms of the carboxyl group coverage on the PS latex particles; these results confirmed that the carboxyl groups significantly influenced the modulus through the mechanism of a glassy interphase formation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2788–2801, 2002
Effect of the thermal treatment of ionomer films on permeability and permselectivity
Authors: Al‐Ati Tareq , Hotchkiss Joseph H. 
Published: October 2002

AbstractIonomers have been studied in detail and have gained widespread commercial use. Interested in altering the ratio of CO2/O2 permeability (i.e., permselectivity) of films for use in packaging respiring produce, we pressed sodium‐neutralized poly(ethylene methacrylic acid) ionomers into films at 120–160°C and investigated their thermal, morphological, and permeability properties. The heat treatment of the ionomers at 160°C increased the gas permeability for O2 more than for CO2 and reduced the CO2/O2 permselectivity ratio from 4.1 to 1.6. The reasons for these changes in the permeability characteristics of the ionomers are not understood but could be related to a reduction in the polyethylene (PE) crystallinity and the destruction of the aggregates into smaller, dispersed clusters. These results were supported by differential scanning calorimetry data and scanning electron micrographs. This suggests that the heat treatment of ethylene–methacyrlic ionomers may improve their potential for applications as selective barriers for modified‐atmosphere packaging of respiring produce. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2811–2815, 2002
Synthesis and properties of poly(amide imide)s based on 2,2′‐ or 4,4′‐bis(4‐aminophenoxy)biphenyl and various bis(trimellitimide)s
Authors: Yang Chin‐Ping , Liou Guey‐Sheng , Jeng Shu‐Huei , Chen Ruei‐Shin 
Published: October 2002

AbstractThree series of isomeric poly(amide imide)s (series III, IV, and V) were synthesized by the direct polycondensation of 2,2′‐bis(4‐aminophenoxy)biphenyl (2,2′‐BAPB), 4,4′‐bis(4‐aminophenoxy)biphenyl (4,4′‐BAPB), or their equimolar mixture (2,2′‐BAPB/4,4′‐BAPB = 1/1) with 12 diimide diacids and with triphenyl phosphite and pyridine as condensing agents. A comparison of the physical properties of these three series was also made. The inherent viscosities of series III, IV, and V were 0.25–0.84, 0.25–1.52, and 0.43–1.30 dL g−1, respectively. Most of the series III polymers showed better solubility because of the non‐para structure, with the solubility order found to be III > V > IV. According to X‐ray diffraction patterns, the amorphous poly(amide imide)s had excellent solubility, whereas the crystalline polymers were less soluble. All the soluble polymers afforded transparent, flexible, and tough films, which had tensile strengths of 57–104 MPa, elongations at break of 3–20%, and initial moduli of 2.05–2.86 GPa. The glass‐transition temperatures (measured by differential scanning calorimetry) were highest for series IV, which contained the rigid 4,4′‐biphenyl units (254–299°C); copolymer series V ranked second (237–277°C), and series III, with crank 2,2′‐biphenyl structures, had the lowest values (227–268°C). The 10% weight‐loss temperatures (measured by thermogravimetric analysis) were close to one another, ranging from 527 to 574°C in nitrogen and from 472 to 543°C in air. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2763–2774, 2002
Radiation‐induced graft polymerization of methyl methacrylate onto ultrahigh molecular weight polyethylene in the presence of a metallic salt and acid
Authors: Kwon Oh Hyun , Nho Young Chang 
Published: October 2002

AbstractAn attempt was made to graft methyl methacrylate (MMA) onto ultrahigh molecular weight polyethylene preirradiated in air in the presence of a metallic salt and acid. The grafting yield increased with increasing monomer concentration. The maximum grafting yield was around a 60 vol % monomer concentration. The results showed that the inclusion of FeSO4 · 7H2O and sulfuric acid in MMA grafting solutions was extremely beneficial and led to a most unusual synergistic effect in the radiation grafting, much more than with only a metallic salt. However, CuSO4 · 5H2O led to a detrimental effect. It is believed that sulfuric acid accelerates the decomposition of hydroperoxides in the presence of metallic salts such as Fe2+, inhibiting homopolymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2348–2356, 2002
Graft copolymerization of acrylamide–methylacrylate comonomers onto cellulose using ceric ammonium nitrate
Authors: Gupta K. C. , Khandekar Keerti 
Published: October 2002

AbstractThe graft copolymerization of acrylamide–methylacrylate comonomers was carried out using ceric ammonium nitrate as initiator in the presence of nitric acid at 25 ± 1°C. The effects of feed molarity, feed composition, reaction time, and temperature on graft yield (%G) and other grafting parameters were investigated. The determination of rate of ceric (IV) ions disappearance as a function of feed molarity and reaction time was useful in the determination of the rate of ceric (IV) ions consumption during graft copolymerization. The graft yield (%G) in the presence of acrylamide increases because of the synergistic effect of acrylamide comonomer. The composition of the grafted chains (FAAm) varies on varying the feed composition and reaction temperature but is almost constant during feed molarity variation. The Mayo and Lewis method was used to determine the reactivity ratios of acrylamide (r1) and methylacrylate (r2), which are 0.65 and 1.07, respectively. The product of reactivity ratio (r1
r2) is less then unity; hence, an alternate arrangement of comonomer blocks in the grafted copolymer chain is proposed. The rate of graft copolymerization of comonomers onto cellulose is second power to the concentration of comonomers and square root to the concentration of ceric ammonium nitrate. Suitable reaction steps for graft copolymerization of comonomers onto cellulose are proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2631–2642, 2002