bluuebunny/crossref_metadata_2025_split huggingface dataset:
Speciation of volatile antimony compounds in culture headspace gases of Cryptococcus humicolus using solid phase microextraction and gas chromatography–mass spectrometry
Authors: Smith L. M. , Maher W. A. , Craig P. J. , Jenkins R. O. 
Published: August 2002

AbstractDirect analysis of the volatile antimony compounds stibine (SbH3), monomethylantimony, dimethylantimony (Me2Sb) and trimethylantimony (Me3Sb) using solid phase microextraction (SPME) with polydimethylsiloxane fibres and gas chromatography–mass spectrometry (GC–MS) is described. The best analyte to background signal ratio was achieved using a 20 min extraction time. Antimony species were separated using a 3% phenylmethylsilicone capillary column operated at a column pressure of 70 kPa, a flow rate of 1.4 ml min−1 and temperature ramping from 30 to 36 °C at 0.1 °C min−1. Cryogenic focusing of desorbed species was required to achieve resolution of antimony species. The optimized SPME–GC–MS method was applied to the analysis of headspace gases from cultures of Cryptococcus humicolus incubated with inorganic antimony(III) and (V) substrates. The headspace gases from biphasic (aerobic–anaerobic) biomass‐concentrated culture incubations revealed the presence of SbH3, Me2Sb and Me3Sb. Stibine was the major antimony species detected in cultures amended with inorganic antimony(V). Me3Sb was the sole volatile antimony species detected when cultures were amended with antimony(III). Copyright © 2002 John Wiley & Sons, Ltd.
Organotin speciation analyses in marine biota using sodium tetraethylborate ethylation and gas chromatography with flame photometric detection
Authors: Cassi Roberto , Tolosa Imma , Bartocci Jean , Mora Stephen de 
Published: August 2002

AbstractThe analysis of organotin compounds based on the in situ simultaneous derivatization and extraction with sodium tetraethylborate has been optimized to overcome the most common matrix effect problems with biological samples. To obtain a complete dissolution of the samples, free of colloidal interfaces problems, mechanical agitation has been coupled with stirring in a warmed ultrasonic bath. A strict quality control system using three internal standards was implemented. Tripropyltin chloride was used as internal standard to assess the derivatization reaction and tetraoctyltin was used to check the overall extraction efficiency. Tetrabutyltin was used to verify the gas chromatography (with flame photometric detector) performance of the analyses. The technique was validated using Certified Reference Materials (NIES‐11 and BCR‐477) and has been applied successfully to different biological matrices (fish, mussels, oyster and barnacles). Copyright © 2002 John Wiley & Sons, Ltd.
Morphological analysis of linear low density polyethylene films by atomic force microscopy
Authors: Drummond Kate M. , Shanks Robert A. , Cser Ferenc 
Published: August 2002

AbstractAtomic force microscopy has been used to investigate the morphology of hexene linear low density polyethylene (LLDPE) blown film in the undrawn and drawn states. The morphology of the undrawn film, which is biaxially oriented due to the nature of the extrusion process, is composed of crystallites, which consist of aggregates of lamellae. Elongation of the film caused these crystallites to undergo deformation, resulting in the gradual formation of a fibrillar structure in the draw direction. The transformation of these crystallites into fibrils corresponded with an initial increase in the surface roughness, until 250% elongation. Further extension of the film to 450% caused the surface roughness to reach a plateau. The changes observed in the surface roughness and morphology indicate that drawing of the film caused the crystallites to tilt and slip, rupturing crystalline blocks, which then develop into a fibrillar structure. Further extension of these initial fibrillar structures resulted in a more oriented fibrillar morphology. Wide‐angle x‐ray scattering clearly showed the orientation of the crystals with respect to the draw direction throughout the film. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 777–784, 2002
Mechanical properties, morphology, and crystallization behavior of new thermoplastic polyimide (N‐TPI)/poly(ether sulfone) blends
Authors: Shibata Mitsuhiro , Ozawa Koichi , Yosomiya Ryutoku 
Published: August 2002

AbstractBlends of wholly aromatic new thermoplastic polyimide (N‐TPI) and poly(ether sulfone) (PES) were prepared by melt‐mixing and subsequent injection molding. Their mechanical properties, morphology, and crystallization behavior were investigated. A synergistic effect on the flexural properties was observed for the N‐TPI/PES blends over the whole compositions. Differential scanning calorimetric analysis confirmed that the blend is an immiscible system and that the crystallinity of the N‐TPI component is very low (0.4–1.4%) irrespective of the composition. Scanning electron microscopic analysis suggested that the improvement in flexural properties is likely due to the reinforcement of the PES matrix by the fibrous N‐TPI phase for the N‐TPI/PES (40/60, 20/80) blends. For N‐TPI/PES (80/20, 60/40), the orientation of the matrix N‐TPI rather than the fibrillation of the PES phase along the melt‐flow direction may contribute to the synergism observed. Also, study of the isothermal crystallization behavior of the blends revealed that the addition of 10 wt % PES accelerates the crystallization of N‐TPI and further addition causes the retardation of it. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1366–1374, 2002
Grafting of poly(acrylic acid) onto cellulosic microfibers and continuous cellulose filaments and characterization
Authors: Loría‐Bastarrachea M. I. , Carrillo‐Escalante H. J. , Aguilar‐Vega M. J. 
Published: August 2002

AbstractResults from the grafting of poly(acrylic acid) (PAA) onto cellulosic microfibers and continuous cellulose filaments are presented. The grafting of PAA onto cellulosic fibers offers the possibility of developing enhanced ion exchange and fluid absorbency on the fibers. The grafting of PAA was carried out with a two‐step procedure. First, vinyl‐terminated ethoxy silane was deposited on the surface of the fiber. This was followed by a grafting polymerization reaction in aqueous media of acrylic acid with different concentrations of potassium persulfate (KPS), which acted as the initiator. The percentage of grafting increased with increasing KPS concentration and reached a maximum value at a concentration of about 0.4 wt % with respect to the weight of the fiber. The grafted copolymer was characterized by Fourier transform infrared spectroscopy. Strong evidence that the grafting reaction was successful was given by the presence of a band, with a maximum at 1732 cm−1, that was characteristic of carbonyl group absorption and was not initially present in the cellulosic fibers. The water absorption of the cellulosic microfibers grafted with PAA was three times greater than the water absorption of the nongrafted microfibers. The mechanical properties of continuous cellulose filaments did not change drastically with PAA grafting. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 386–393, 2002
Study of the crystal structure of P(HBA/HNA)/PET blend fibers
Authors: Xiao Changfa , Zhang Yufeng , Wu Shizhen , Takahashi Toshisada 
Published: August 2002

AbstractThe crystal structure of p‐hydroxybenzoate/2‐hydroxy‐6‐naphthoic acid copolyester [P(HBA/HNA)]/poly(ethylene terephthalate) (PET) blend (ACPET) fiber was studied with wide‐angle X‐ray diffraction and differential scanning calorimetry. The results showed that crystallites of P(HBA/HNA) and PET were formed in ACPET fibers; that is, some crystallites of ACPET fiber were composed of PET chains, and others were composed of P(HBA/HNA) chains. The thermal behaviors of the crystals of each component in the blend fiber were different from those of each corresponding pure component. For the fibers heat‐treated at 300 and 350°C, the degree of supercooling of P(HBA/HNA) segments in the blend fibers was the same as that of P(HBA/HNA) fiber, but the degree of supercooling of PET in the blend fibers was distinctly higher than that of pure PET fibers. Evidently, the aforementioned changes were attributable to the blending of PET with P(HBA/HNA). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 394–400, 2002
Competitive sorption of water vapor and CO2 in photocrosslinked PVCA film for a capacitive‐type humidity sensor
Authors: Matsuguchi Masanobu , Maeda Nozomi , Sakai Yoshiro 
Published: August 2002

AbstractThe sorption behavior of water vapor and CO2 gas in photocrosslinked poly(vinyl cinnamate) (PVCA) film was examined at 30°C under atmospheric pressure. Both the water sorption isotherm and the CO2 sorption isotherm obtained with quartz crystal microbalance (QCM) method obeyed the simple Langmuir's equation. Water vapor/CO2 mixed‐gas sorption isotherms were also obtained. Total amount of sorbed mixed gases was clearly influenced by the partial pressure of water vapor (pw) and CO2 gas (pc) in the atmosphere. A modified Langmuir's equation based on a dual‐site model was employed for predicting the competitive adsorption isotherm, and the isotherm was clearly described by the equation. The theoretically estimated amount of adsorbed water at the constant pw decreased slightly with increasing pc. The effect of this phenomenon on the sensitivity of the capacitive‐type relative humidity sensor was examined. As expected, the electrical capacitance of the sensor at the constant relative humidity decreased because of the coexistence of CO2 gas. However, the influence was quite small in the CO2 concentration range in the ordinary environment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 401–407, 2002
Studies on compression behavior of carbon–epoxy laminates with and without buffer‐strip layers in dry and water‐absorbed conditions
Authors: Kishore  , Khan Bijoysri , Viswanath B. 
Published: August 2002

AbstractThis work looks at the compression behavior of laminated carbon–epoxy (C–E) composites with inserted interleaved polytetrafluoroethylene‐coated fabric material at different locations either continuously or discontinuously within the specimen. Also, the effect of water ingress in these specimens on the strength values is reported. Although significant differences were noticed in the trend of the strengths for different architectural arrangements in dry and water‐immersed samples, significant differences for the modulus was less perceptible. The introduction of small amounts of less‐adherent layers of material at specific locations causes a decrement in the load‐carrying capability of the C–E system. It is further observed that with an increase in the number of buffer/delaminating strips insertions, the water ingress increases and the compressive strength values decrease. Examination of the samples, noting macroscopic features including the interfacial regions, assisted in observing a correlation between the observed strength values, architecture, and the failure mode. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 408–416, 2002
Synthesis of poly(vinyl alcohol) phosphorylate–dicyandiamide–formaldehyde resin complex and its absorption of rare earth ions
Authors: Su Zhi‐Xing , Zhou Yun‐Bin , Chang Xi‐Jun , Jin Yi , Qi Shang‐Kui 
Published: August 2002

AbstractPoly(vinyl alcohol) phosphorylate was prepared and its complex with dicyandiamide–formaldehyde resin was used for adsorption and separation of Sm3+, Nd3+, Gd3+, Ho3+, and Er3+ ions. The factors that affect the adsorption and separation of these ions on the polyacid–polybase complex, such as the acidity of the sample solution, adsorption capacity, and conditions of desorption, were investigated by means of spectrophotometry and inductively coupled plasma optical emission spectrometry. IR spectrometry and X‐ray photoelectric spectrometry were used to study the adsorption mechanism, and the probably coordination structure was given. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 962–968, 2002; DOI 10.1002/app.10197
Activation of bifunctional coupling agents in fiberglass/polyethylene composites by electron beam
Authors: Van Dyke J. D. , Gnatowski Marek , Burczyk Andrew 
Published: August 2002

AbstractElectron beam (EB) radiation was investigated as a means to initiate coupling between the fiberglass and plastic phases in fiberglass/polyethylene plastic composites using two bifunctional compounds, 12‐azido‐1‐diazo‐2‐dodecanone (A) and 1‐diazo‐17‐octadecene‐2‐one (B). Chemical studies reveal that EB radiation has the potential to bind both of these compounds to fiberglass. Fiberglass coated with either A or B shows reduced values of percentage recovery upon exposure to EB, indicating a reaction between these compounds and the glass surface. However, even 400 kGy of radiation was not as effective as a heat treatment for 45 min at 150°C. To test the effectiveness of EB radiation to couple these compounds to polyethylene, fiberglass samples were heat‐treated with compounds A and B, followed by extrusion mixing with polyethylene, and exposure of molded tensile and impact samples to EB radiation. Compound B showed the best overall ability to couple with the polyethylene matrix, but a 400‐kGy dose was necessary to bring about substantial coupling. At 400 kGy, samples containing B showed a 23% improvement in tensile properties and a 30% change in Izod impact. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2579–2594, 2002
Improvement in impact property of continuous glass mat reinforced polypropylene composites
Authors: Zhou Xiaodong , Dai Gance , Lin Qunfang 
Published: August 2002

AbstractThe toughened polypropylene (PP) was obtained by the blending of PP with ethylene‐propylene diene monomer (EPDM). The impact property of continuous glass mat‐reinforced polypropylene was adjusted through three ways: different toughness PPs and their blends were used as matrices, the functionalized polypropylene was added into the matrix to control the interfacial adhesion; the ductile interlayer was introduced at the fiber/matrix interphase by the grafting and crosslinking of rubber chains on fiber surface. The effect of PP toughness, interfacial adhesion, and ductile interlayer on the mechanical properties of composite systems was studied. The impact toughness of GMT increased with increasing the matrix toughness, whereas the flexural strength and modulus decreased. The good interfacial adhesion resulted in the low impact toughness. However, GMT composite with high strength, modulus, and impact toughness could be obtained by the introduction of a ductile interlayer at fiber/matrix interphase. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2680–2688, 2002
Pertraction of cations in a hybrid membrane system containing soluble polymeric ionophores
Authors: Wódzki Romuald , Świątkowski Marek , Kałużyński Krzysztof , Pretula Julia 
Published: August 2002

AbstractA hybrid membrane system composed of two insoluble cation‐exchange membranes (Nafion) and a liquid membrane in between was studied. A series of organic and aqueous liquid membranes containing soluble polymers as macromolecular ionophores (macroionophores) was prepared and tested. The pertraction (membrane‐transport) characteristics of poly(ethylene glycol) and its ionizable derivatives, including as poly[poly(oxyethylene) phosphate] (PPOEP) and di‐[ω‐methoxy poly(oxyethylene)] phosphate, were measured and are discussed as dependent on the composition and molecular mass of a macroionophore. The liquid membrane composed of PPOEPs dissolved in dichloroethane combined the cation‐exchange properties with neutral coordination functionalities introduced by the poly(oxyethylene) backbone of this ionophore. The overall fluxes, facilitation factors, and the membrane system selectivity were measured in the carrier‐mediated pertraction of transient metal cations (Cu2+, Zn2+, Mn2+, Co2+, and Ni2+). PPOEP could facilitate the pertraction of Zn2+ and Cu2+ over Ni2+ and Co2+. In the case of an aquatic hybrid membrane system, high but nonselective ionic fluxes were observed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 99–109, 2002; DOI 10.1002/app.10263
Hydroxyalkylation of parabanic acid. I. Reactions with formaldehyde
Authors: Zarzyka‐Niemiec Iwona , Lubczak Jacek 
Published: August 2002

AbstractThe results of investigations into the reaction of parabanic acid with formaldehyde at different molar ratios of the reagents are presented. A fast and effective method of synthesis of N,N′‐bis(hydroxymethyl)parabanate was developed. The reaction of parabanic acid with an excess of formaldehyde was analyzed and the structure of the products proposed. Conditions at which the hydroxymethyl derivatives of parabanic acid undergo self‐condensation as well as prospects of using them in subsequent oxyalkylation with oxiranes are specified. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2858–2872, 2002; DOI 10.1002/app.10274
Equivalent processing time analysis of glass transition development in epoxy/carbon fiber composite systems
Authors: Park In‐Kyung , Lee Doo‐Sung , Nam Jae‐Do 
Published: August 2002

AbstractThe cure kinetics and glass transition development of a commercially available epoxy/carbon fiber prepreg system, DMS 2224 (Hexel F584), was investigated by isothermal and dynamic‐heating experiments. The curing kinetics of the model prepreg system exhibited a limited degree of cure as a function of isothermal curing temperatures seemingly due to the rate‐determining diffusion of growing polymer chains. Incorporating the obtained maximum degree of cure to the kinetic model development, the developed kinetic equation accurately described both isothermal and dynamic‐heating behavior of the model prepreg system. The glass transition temperature was also described by a modified DiBeneditto equation as a function of degree of cure. Finally, the equivalent processing time (EPT) was used to investigate the development of glass transition temperature for various curing conditions envisioning the internal stress buildup during curing and cooling stages of epoxy‐based composite processing. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 144–154, 2002; DOI 10.1002/app.10282
Study of the influence of the reaction parameters on the composition of the metallocene‐catalyzed ethylene copolymers using temperature rising elution fractionation and 13C nuclear magnetic resonance
Authors: Barrera Griselda , Galland  , Santos Raquel , Mauler  , Portal Luciana , Silva Da , Liberman Susana , Arli Adilson , Silva Da , Filho  , Quijada Raúl 
Published: August 2002

AbstractPolyethylene copolymers prepared using the metallocene catalyst rac‐Et[Ind]2ZrCl2 were fractionated by preparative Temperature Rising Elution Fractionation (p‐TREF) and characterized by 13C nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) to study the heterogeneity caused by experimental conditions. Two ethylene–1‐hexene copolymers with different 1‐hexene content and an ethylene–1‐octene copolymer all obtained using low (1.6 bar) ethylene pressure were compared with two ethylene–1‐hexene copolymers with different 1‐hexene content obtained at high ethylene pressure (7.0 bar). Samples obtained at low ethylene pressure and with low 1‐hexene concentration in the reactor presented narrow distributions in composition. Samples prepared with high comonomer concentration in the reactor or with high ethylene pressure showed an heterogeneous composition. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 155–163, 2002; DOI 10.1002/app.10284
Poly(1,3‐disila‐1,3‐diphenyl‐2‐oxaindane)– poly(dimethylsiloxane) block copolymers
Authors: Mukbaniani O. , Matsaberidze M. , Karchkhadze M. , Khananashvili L. , Achelashvili V. 
Published: August 2002

AbstractThe hydrolytic condensation of 1,3‐dichloro‐1,3‐disila‐1,3‐diphenyl‐2‐oxaindane under neutral conditions produced α'ω‐dihydroxy‐1,3‐disila‐1,3‐diphenyl‐2‐oxaindane (polymerization degree ≈ 4). The homofunctional condensation of α'ω‐dihydroxy‐1,3‐disila‐1,3‐diphenyl‐2‐oxaindane in a toluene solution and in the presence of activated carbon was performed, and dihydroxy‐containing oligomers with various degrees of condensation were obtained. Through the heterofunctional condensation of dihydroxy‐containing oligomers with α'ω‐dichlorodimethylsiloxanes in the presence of amines, corresponding block copolymers were obtained. Gel permeation chromatography, differential scanning calorimetry, thermomechanical analysis, thermogravimetry, and wide‐angle roentgenography investigations were carried out. Differential scanning calorimetry and roentgenography studies of the block copolymers showed that their properties were determined by the ratio of the lengths of the flexible and linear poly(dimethylsiloxane) and rigid poly(1,3‐disila‐1,3‐diphenyl‐2‐oxaindane) fragments in the macromolecular chain. At definite values of the lengths of the flexible and rigid fragments, a microheterogeneous structure was observed in the synthesized block copolymers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1409–1417, 2002; DOI 10.1002/app.10335
Phenol‐modified polypropylenes as adhesion promoters in glass fiber–reinforced polypropylene composites
Authors: Eteläaho P. , Järvelä P. , Stenlund B. , Wilén C.‐E. , Nicolas R. 
Published: August 2002

AbstractThis publication is based on research work done on functional phenol‐modified polypropylenes (PPs) as adhesion promoters in glass fiber–reinforced PP composites. The glass fiber roving was first impregnated with different combinations of functional polymers and polypropylene in a melt impregnation die attached to an extruder to obtain prepreg. The prepreg was then tested in many ways both macro‐ and micromechanically. The tests included notched tensile tests, optical and electron microscopy, and DMTA (dynamic mechanical thermal analyzer) and DSC (differential scanning calorimetry) analyses as well as determination of the glass content. The tests were run on prepregs containing pure PP, PP with a commercial adhesion promoter, and PP with a number of functional, mostly phenol‐based, polymers. Also, single‐fiber tests were performed on individual glass fibers to test the level of adhesion with the above‐mentioned material combinations. With these tests it could be seen that some of the phenol‐based functional polymers provided the prepreg with better adhesion between the fibers and the matrix than did the commercial adhesion promoter. Optical and electron microscopy also were used in determining the level of adhesion as well as the deformation and fracture mechanisms of the prepreg. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1203–1213, 2002; DOI 10.1002/app.10441
High solids content emulsions. II. Preparation of seed latices
Authors: Schneider M. , Graillat C. , Guyot A. , McKenna T. F. 
Published: August 2002

AbstractThe preparation of concentrated seed latices for use in bimodal and trimodal formulations is presented in the current work. Various recipes of surfactant and initiator were tested in order to allow us to control the number of particles produced during the nucleation stage. Following this, a semi‐batch feed recipe that combined the use of oil‐soluble initiators and pre‐emulsified monomer was used to produce well‐defined latices having well defined particle size distributions. It was found that the primary concern in maintaining latex stability and favorable viscosity was the reduction of undesirable secondary nucleation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1897–1915, 2002; DOI 10.1002/app.10512