bluuebunny/crossref_metadata_2025_split huggingface dataset:
Peroxosalts initiated graft copolymerization of aniline onto rayon fiber—A kinetic approach
Authors: Anbarasan R. , Jayaseharan J. , Sudha M. , Devi J. Lakshmi , Nirmala P. V. , Gopalan A. 
Published: August 2002

AbstractOxidative chemical polymerization of aniline was carried out using peroxydisulphate and peroxomonosulphate as a lone initiator in an aqueous acidic medium in the presence of Rayon fiber. The Rayon fiber was tested for the chemical grafting of polyaniline onto it. The content of polyaniline (wt %) in the backbone was found to vary while varying the [M], [I], and (amount of Rayon fiber) during the polymerization of aniline. Various graft parameters like rate of grafting, % grafting, and % efficiency were calculated. Rate of homopolymerization was also followed for both cases. The chemical grafting was confirmed using FTIR spectroscopy, cyclic voltammetry, weight loss study, and conductivity measurements. Probable mechanism has been proposed to explain the experimental results obtained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 468–478, 2001
Mechanical properties and superstructure of isotactic polypropylene fibers prepared by continuous vibrating zone‐drawing
Authors: Suzuki Akihiro , Sugimura Toshio , Kunugi Toshio 
Published: August 2002

AbstractA continuous vibrating zone‐drawing (CVZD) was applied to study the effect of vibration on the mechanical properties and superstructure of isotactic polypropylene fibers. The CVZD treatment was a new drawing method by which the fiber was continuously drawn at a rate of 0.5 m/min under vibration using the specially designed apparatus. The CVZD treatment was carried out in five steps at a drawing temperature of 150°C and a frequency of 100 Hz, and applied tensions increased step by step with processing in the range of 14.8 to 207 MPa. The obtained fiber had a birefringence of 0.0373, crystallinity of 62.4%, tensile modulus of 17.6 GPa, and tensile strength of 1.11 GPa. These values are higher than those of the continuous zone‐drawn isotactic polypropylene fiber previous reported. The vibration added to the fibers during the zone‐drawing was effective in developing amorphous orientation and improving the mechanical properties. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 600–608, 2001
Synthesis, characterization of polyacrylate‐g‐carbon black and its application to soap‐free waterborne coating
Authors: Li Wei , Xie Zhiming , Li Zhuomei 
Published: August 2002

AbstractPolyacrylate‐g‐Carbon Black (abbrev. as gCB) was prepared by free radical polymerization of acrylate monomers on the carbon black surface, which was initiated by a redox system consisting of cerium ammonium nitrate and hydroxymethyl carbon black. gCB was ascertained by X‐ray Photoelectron Spectrometry (XPS). The optimum conditions of synthesis were studied. The stabilities of gCB dispersing in water were studied by zeta potential measurement and spectrophotometric analysis. The results showed that gCB could disperse in water better than the ungrafted carbon black. gCB could be dispersed in the soap‐free hydrosol forming a colored soap‐free water‐borne coating with satisfactory comprehensive performance. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1100–1106, 2001
Adsorption of blood proteins on glow‐discharge‐modified polyurethane membranes
Authors: Kayirhan Nesrin , Denizli Adil , Hasirci Nesrin 
Published: August 2002

AbstractPolyurethanes are a class of polymers that have a wide range of applications in the medical field although their blood compatibility still needs improvement. In order to obtain medical purity, this study prepared membrane‐form polyurethanes from toluene 2,4‐diisocyanate (TDI) and poly(propylene ethylene glycol) without the addition of any ingredients such as solvents, catalysts, or chain extenders. The aim was to increase surface hydrophilicity and improve blood compatibility. Therefore, the prepared membranes were modified by treatment with oxygen or argon plasmas. Characterizations of the samples were achieved by contact‐angle and water‐uptake studies as well as from atomic force microscope (AFM) pictures. It was found that oxygen‐modified samples were more hydrophilic than argon‐modified samples. The AFM images showed that surface roughness increased with plasma treatment. The protein adsorption experiments carried out with single protein solutions demonstrated that the adsorption of bovine serum albumin and fibrinogen decreased drastically by increasing the applied power and exposure time of the glow discharge. A similar decrease in the adsorption of protein was also observed for human blood proteins. The alterations of the conformational structures of the adsorbed proteins were examined by fluorescence spectrophotometry. Similar spectra with the same maximum wavelength were observed for native and desorbed proteins. These results showed that no denaturation of the proteins occurred upon adsorption on the surfaces of the prepared membranes. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1322–1332, 2001
Syntheses and magnetic properties of novel bithiazole‐containing polymeric complexes
Authors: Weng Jian , Sun Weilin , Jiang Liming , Shen Zhiquan 
Published: August 2002

AbstractThree novel bithiazole‐containing polymers were synthesized from 2,2′‐diamino‐4, 4′‐bithiazole (DABT) condensed with bismaleimide, bis(methyloxycarbonyl ethyl)tin dichloride (BETD), and 4,4′‐diphenylmethane diisocyanate (DPDI), respectively. A new series of polymeric complexes were prepared from Fe2+ and the three polymers. These polymers and their complexes were characterized through FTIR, 1H‐NMR, and related techniques. The chemical compositions of the complexes were determined by XPS. The presence of the exchange interaction between the unpaired electrons was investigated by ESR spectroscopy. The magnetic behavior of these complexes was measured as a function of the magnetic field strength (0–40 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1353–1359, 2001
Solid‐phase extraction of phenolic compounds with poly[metalloprotoporphyrin IX]
Authors: Lo Balbo Alfredo , Hurst Jorge , Campo Dall'Orto Viviana , Rezzano Irene 
Published: August 2002

AbstractA highly insoluble metalloporphyrin polymeric material was used as sorbent for the solid‐phase extraction of phenolic compounds. Substantial quantities of phenols (40 to 60 mg/g polymer) were absorbed from aqueous solution comparing satisfactorily with other extraction methods. The polymeric phase presented similar KSPE values for the hydrophobic compounds tested such as p‐chlorophenol, BPA, p‐nitrophenol, and a significant lower value for the more hydrophilic p‐aminophenol and cresol. Several metallic complexes of protoporphyrin IX (Co2+, Cu2+, Ni2+, Zn2+, and Fe3+) have been tested. The analytes were extracted with high recoveries at acid and neutral pH values, whereas at pH 10 low recoveries were obtained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3038–3043, 2001
Cellulose/casein blend membranes from NaOH/urea solution
Authors: Yang Guang , Zhang Lina , Han Hongwei , Zhou Jinping 
Published: August 2002

AbstractCellulose membranes and cellulose/casein blend membranes were successfully prepared from a new solvent system (6 wt % NaOH/4 wt % urea aqueous solution) by coagulation with a sulfuric acid aqueous solution. The structures and properties of the membranes were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), wide‐angle X‐ray diffraction, differential scanning calorimetry, and a tensile test. The experimental results showed that the suitable coagulation condition was 5 wt % H2SO4 for 5 min. When the casein content of the mixture was less than 15 wt %, the blend membranes were miscible because of the interactions between the hydroxyl groups of cellulose and the peptide bonds of casein. The blend membranes with 10 wt % casein had good miscibility, higher crystallinity, and the highest mechanical properties and thermal stability. In this case, the tensile strength and breaking elongation of the blend membranes were 109 MPa and 16%, respectively, and its pore size, obtained by SEM, was 290 nm, which suggests that the blend membranes provide a potential application for the field of separation technology. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3260–3267, 2001
Water‐soluble polymers. LXXXIII. Correlation of experimentally determined drag reduction efficiency and extensional viscosity of high molecular weight polymers in dilute aqueous solution
Authors: Cowan Martin E. , Garner Chad , Hester Roger D. , McCormick Charles L. 
Published: August 2002

AbstractThe extensional viscosity for aqueous solutions of high molecular weight poly(acrylamide) copolymers and poly(ethylene oxide) homopolymers was measured using a laboratory‐designed screen extensional rheometer. A Bingham model was developed to estimate the average local polymer coil extensional viscosity (ηcoil). A strong correlation was found between the measured ηcoil values and the polymer extensional viscosity predicted by a bead‐spring model. The dilute aqueous solution drag reduction was measured with a rotating disk instrument under conditions minimizing the effects of shear degradation. Extensional viscosity and drag reduction measurements were performed in deionized water and in 0.514M sodium chloride. The relative drag reduction efficiency values (Δ) in both solvents were found to strongly correlate with measured ηcoil values. This is the first report of the accurate prediction of drag reduction behavior for a wide range of polymer types in various solvents from the independently measured molecular parameters ηcoil and [η]C. The often‐used relative drag reduction efficiency expressed as the product of [η]C and Δ can now be replaced by the absolute drag reduction efficiency [η]Cηcoil. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1222–1231, 2001
Isotactic polypropylene morphology–Raman spectra correlations
Authors: Wang Xueqin , Michielsen Stephen 
Published: August 2002

AbstractIsotactic polypropylene (iPP) is used in a wide variety of products, including the rapidly growing area of nonwoven fabrics. A new method based on Raman microspectroscopy is developed to determine the morphology of iPP fibers in complex structures through correlations with specific features of the Raman spectra and the birefringence and Lorentz density of a series of fibers. A good correlation is found between the fourth Legendre polynomial (P4) of the principle axis of the Raman tensor of the 841 cm−1 band and the birefringence. Only vibrations that include the CCC backbone stretch correlate well with the birefringence. There is a second, empirical correlation between the birefringence and the depolarization ratios of the 841 and 809 cm−1 Raman bands when the fiber axis is oriented parallel to the laser polarization. The experimental protocol for this empirical correlation is much simpler than for the P4 correlation while simultaneously yielding improved accuracy. There is another empirical correlation between the Lorentz density and the depolarization ratios of the 841 and 1330 cm−1 Raman bands. Thus, the birefringence and Lorentz density of iPP fibers could be determined quantitatively using polarized Raman microspectroscopy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1330–1338, 2001
Flow visualization and extrudate swell of natural rubber in a capillary rheometer: Effect of die/barrel system
Authors: Sombatsompop N. , Dangtungee R. 
Published: August 2002

AbstractAn investigation was carried out to examine the effect of die/barrel system on the flow patterns and extrudate swell of natural rubber in the barrel of a capillary rheometer, using a colored tracer as the visualization technique. The capillary rheometer used in this work had two dies located along the barrel, which is novel in rheometer design. The flow of the rubber in the upper barrel was dependent on the piston/barrel action and changed with piston displacement, whereas the complexity of the flow in the lower barrel was dependent not only on the piston displacement, but also on the geometry of the upper die design. The flow patterns that developed in the whole barrel were independent of the die located at the bottom of the barrel. In addition, the change in extrudate swell was associated with the flow occurring in the barrel, residence time, elastic characteristic, and the temperature rise during the flow. It was concluded that the general style of the flow patterns of natural rubber was greatly dependent on the die geometry that the material had previously moved past. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2525–2533, 2001
Atomic force microscopy (AFM) study of poly(ethylene terephthalate‐co‐4,4′‐bibenzoate): A polymer of intermediate structure
Authors: Schiraldi D. A. , Occelli M. L. , Gould S. A. C. 
Published: August 2002

AbstractAn atomic force microscope (AFM) operating in both tapping and contact modes was used to study the surface topography and the molecular organization of a molded flexural test bar prepared from a poly(ethylene terephthalate‐co‐4,4'‐bibenzoate) copolymer containing a terephthalate:4,4′‐bibenzoate molar ratio of 45:55 (PETBB‐55). Micrometer‐scale (15 × 15 μm) contact‐mode AFM images revealed that the PETBB surface contains a deep indentation that forms trenches that extend over the entire surface examined. In addition, the surface may appear as an overlay of fibrils having different orientation. At greater magnification (1 × 1 μm), it is possible to observe the existence of micropores. These results were also observed in images obtained while operating the AFM in the tapping mode. The side of the part is more homogeneous and ordered than is its top surface. It has the appearance of a stacked lamellar structure in which missing fibrils can originate cracks ∼0.5‐μm wide. Fine surface details were observed in nanometer‐scale images, showing the presence of chains of white spots that could represent molecules or a cluster of molecules. These chains can form domains in which they are almost parallel to each other and have a preferred orientation; this structural organization was generated without any orientation other than that produced during a mold flow. Alternatively, chain lengths are interrupted and white spots form, distorted by easily recognizable hexagonal arrangements. The degree of lamellar order observed in the side of the bar, the area of greatest flow orientation in the part, was not been observed for the PET homopolymer in the past and bears some resemblance to previously imaged liquid crystalline polyester (LCP) structures. Combined with some previously reported LCP‐like mechanical properties, we propose that this PETBB copolymer is, in fact, a “frustrated LCP,” one that with some driving force could be converted to liquid crystallinity. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2616–2623, 2001
Synthesis and characterization of thermoplastic polyurethanes as binder for novel thermoplastic propellant
Authors: Duo Yingquan , Tan Huimin , Chen Futai 
Published: August 2002

AbstractTwo series of thermoplastic polyurethanes (TPUs), which used nitroester plasticiable tetrahydrofuran‐ethylene oxide random copolyether as soft segment and adduction products of isophorone diisocyanate (IPDI) and toluene diisocyanate (TDI) with 1,4‐butanediol as hard segments respectively, were successfully synthesized as binders for novel thermoplastic propellant. Mechanical tests and DSC techniques were applied to make characterizations of the polymers in order to choose candidate materials. Results shown that the TPU based on IPDI with fraction of the hard segment around 45% will meet requirements of propellant in terms of mechanical properties and glass transition of the soft segment phase. The results were further manifested in detail by quantitative studies of the degree of microphase separation as well as hydrogen bonding within the hard segment domain based on the equations established through FTIR and DSC analyses. It was found that mixing of two phases, which mainly referred to the mount of the hard segment dissolving into the soft segment phase, was as little as 10% in IPDI series TPUs, whereas it was almost up to 30% in TDI series. This indicated that better phase separation was achieved in IPDI series TPU. By contrast, studies of hydrogen bonding in domain revealed that the domain of TPUs prepared with TDI was much oriented in comparison with that with IPDI, which indicated higher processing temperatures. The results were raised by the melting index results under required conditions. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2961–2966, 2002; DOI 10.1002/app.2324
Biomonitoring of heavy metal contamination along the Salento coast (Italy) by metallothionein evaluation in Mytilus galloprovincialis and Mullus barbatus
Authors: Lionetto M.G. , Giordano M.E. , Caricato R. , Pascariello M.F. , Marinosci L. , Schettino T. 
Published: August 2002

Abstract1. The aim of the present study was to identify possible ecotoxicological risk of heavy metal contamination along the coast of the Salento Peninsula (South of Italy) evaluating levels of metallothioneins (Mts), by a spectrophotometric method, in two bioindicator species: Mytilus galloprovincialis and Mullus barbatus.2. Cellular stress response to heavy metals, indicated by increased levels of Mt, measured in marine organisms can represent an early warning of heavy metal contamination along the Salento coast particularly at the hot spot of Brindisi and act as an alert for possible toxic effects on higher level organisms. Copyright © 2001 John Wiley & Sons, Ltd.
The human cadaver in the age of biomedical informatics
Authors: Aziz M. Ashraf , Mckenzie James C. , Wilson James S. , Cowie Robert J. , Ayeni Sylvanus A. , Dunn Barbara K. 
Published: August 2002

AbstractMajor national and international critiques of the medical curriculum in the 1980s noted the following significant flaws: (1) over‐reliance on learning by rote memory, (2) insufficient exercise in analysis and synthesis/conceptualization, and (3) failure to connect the basic and clinical aspects of training. It was argued that the invention of computers and related imaging techniques called to question the traditional instruction based on the faculty‐centered didactic lecture. In the ensuing reform, which adopted case‐based, small group, problem‐based learning, time allotted to anatomical instruction was severely truncated. Many programs replaced dissection with prosections and computer‐based learning. We argue that cadaver dissection is still necessary for (1) establishing the primacy of the patient, (2) apprehension of the multidimensional body, (3) touch‐mediated perception of the cadaver/patient, (4) anatomical variability, (5) learning the basic language of medicine, (6) competence in diagnostic imaging, (7) cadaver/patient‐centered computer‐assisted learning, (8) peer group learning, (9) training for the medical specialties. Cadaver‐based anatomical education is a prerequisite of optimal training for the use of biomedical informatics. When connected to dissection, medical informatics can expedite and enhance preparation for a patient‐based medical profession. Actual dissection is equally necessary for acquisition of scientific skills and for a communicative, moral, ethical, and humanistic approach to patient care. Anat Rec (New Anat) 269:20–32, 2002. © 2002 Wiley‐Liss, Inc.
Ultrastructure of canine type II pneumocytes during hypothermic ischemia of the lung: A study by means of conventional and energy filtering transmission electron microscopy and stereology
Authors: Ochs Matthias , Fehrenbach Heinz , Richter Joachim 
Published: August 2002

AbstractAlterations in pulmonary surfactant have been reported to be associated with ischemia/reperfusion injury in experimental and clinical lung transplantation. It is unknown whether these alterations are due to damage to surfactant synthesizing type II pneumocytes during hypothermic ischemic storage. The aim of the present study was to examine the effects of hypothermic ischemic storage of the lung on canine type II pneumocytes by means of conventional (CTEM) and energy filtering TEM (EFTEM) and stereology. The lungs of 18 dogs were fixed for TEM immediately after cardiac arrest (6 double lungs) and after storage in Tutofusin® at 4°C for 20 min, 4 hr, 8 hr, and 12 hr (6 single lungs, respectively). Using a systematic uniform random sampling scheme, type II pneumocytes were analyzed qualitatively and stereologically. The relative phosphorus content of cell organelles, especially the surfactant containing lamellar bodies, was investigated by EFTEM. By CTEM, no major qualitative alterations could be observed in type II pneumocytes of the experimental groups. Stereologically, no significant changes in the volume densities or the volume‐to‐surface ratios of type II pneumocytes and their lamellar bodies were found. By EFTEM, the highest intracellular phosphorus signals were recorded over lamellar bodies in all experimental groups. No changes in the phosphorus signals were observed during ischemia. These results indicate that the ultrastructure of canine type II pneumocytes and their lamellar bodies is not affected by hypothermic ischemia of the lung up to 12 hr. Structural preservation of intracellular surfactant is possible during prolonged ischemic lung storage. Anat Rec 263:118–126, 2001. © 2001 Wiley‐Liss, Inc.