bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface and pore structure modification of cellulose fibers through cellulase treatment
Authors: Park Sunkyu , Venditti Richard A. , Abrecht David G. , Jameel Hasan , Pawlak Joel J. , Lee Jung M. 
Published: December 2006

AbstractThe surface and pore structure of cellulose fibers have a significant impact on the properties and performance in applications. Cellulase enzymatic hydrolysis of cellulose fibers can result in changes to the surface and pore structure, thus providing a useful tool for fiber modification. This research characterizes these changes using various test methods such as fiber dimension, water retention value (WRV), hard‐to‐remove (HR) water content, freezing and nonfreezing bound water content, polymer adsorption, and crystallinity index. For a high‐dosage cellulase treatment (600 U/g dry solid), the fiber length was significantly decreased and the fibers were “cut” in the cross direction, not in the axial direction. The swelling capacities as measured by the WRV and HR water content increased for the high‐dosage treatment. Three independent measurements (nonfreezing bound water, polymer adsorption, and crystallinity index) are in good agreement with the statement that the amorphous regions of cellulose fibers are a more readily available substrate relative to crystalline regions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3833–3839, 2007
Comparative effects of cobalt carboxylates on the thermo‐oxidative degradation of LDPE films
Authors: Roy P. K. , Surekha P. , Rajagopal C. , Choudhary V. 
Published: December 2006

AbstractThis article reports the effect of three cobalt carboxylates—cobalt stearate (CoSt3), cobalt palmitate (CoPal3), and cobalt laurate (CoLau3)—on the thermo‐oxidative degradation of low‐density polyethylene (LDPE) films prepared by sheeting process. The carboxylates were blended with LDPE in the concentration range of 0.05–0.2% (w/w). The degradation was monitored by techniques such as FTIR spectroscopy, change in the mechanical properties (tensile strength and elongation at break), viscometry, surface electron microscopy, melt flow index measurements, and apparent density measurements. Studies indicate that films containing these additives are highly susceptible to thermo‐oxidative degradation. Oxygen containing functionalities such as carbonyl and vinyl species are generated on the surface of polyethylene because of thermo‐oxidation, as indicated by FTIR studies. This oxidative process is accelerated in the presence of cobalt carboxylates. The degradation of LDPE was found to increase proportionally with concentration as well as with increasing chain length of the cobalt carboxylate, and follow the order CoSt3 > CoPal3 > CoLau3. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3758–3765, 2007
Electrospinning of high‐molecule PEO solution
Authors: Wan Yu‐Qin , He Ji‐Huan , Yu Jian‐Yong , Wu Yue 
Published: December 2006

AbstractElectrospinning is a simple but powerful method for making nanofibers that can then be collected to create porous mats. We expand the range of this technique by making nanofibers from macromolecules with a molecular weight of 3,000,000, namely poly(ethylene oxide) (PEO). Gelation of PEO blocks its spinning by traditional electrospinning. PEO was mixed with pure alcohol, and in specific concentration 10 wt % and under vibration condition, the mixed solution behaves like polymers for electrospinning, the average diameter of the obtained nanofibers is about 100 nm. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3840–3843, 2007
Microbiocidal activity of chitosan‐N‐2‐hydroxypropyl trimethyl ammonium chloride
Authors: Chi Weilin , Qin Caiqin , Zeng Lintao , Li Wei , Wang Wei 
Published: December 2006

AbstractChitosan‐N‐2‐hydroxypropyl trimethyl ammonium chloride (QTS) was prepared by reaction of chitosan with glycidyl trimethylammonium chloride, which was characterized by FTIR. QTS with different molecular weights (Mw 41.55 × 104, 9.02 × 104, 3.57 × 104, and 0.17 × 104) showed biocidal activity on Staphylococcua aureus, Bacillus subtilis, Staphylococcua epidermidis, and Candida albicans. QTS with high molecular weight had high biocidal activity on the gram‐positive bacteria, and the biocidal effect of QTS decreased with decreasing molecular weight from 9.02 × 104 to 0.17 × 104. QTS with Mw 41.55 × 104 exhibits slightly lower biocidal activity on Candida albicans than other QTS samples. However, no remarkable biocidal activity of QTS was found on gram‐negative bacteria Escherichia coli and Pseudomonas aeruginosa at the concentration up to 10 g L−1. Existence of cationic surfactant, amphoteric surfactant, nonionic surfactant, Ca2+ and Mg2+ had no remarkable effect on microbiocidal activity of these QTS samples. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3851–3856, 2007
Synthesis of organic–inorganic hybrid polymeric nanocomposites for the hard coat application
Authors: Hsiao Shu Chuan , Chiang Hau‐Chun , Chien‐Chao Tsiang Raymond , Liu Ta‐Jo , Wu Jeng‐Jaw 
Published: December 2006

AbstractAn organic–inorganic hybrid polymeric nanocomposite has been synthesized for making UV‐curable hard coats. This nanocomposite consists of nano‐sized colloidal silica functionalized with vinyltriethoxysilane (VTES) and dendritic acrylic oligomers (DAO) which have been formed earlier via a reaction of ethylenediamine (EDA) with trimethylopropane triacrylate (TMPTA). Applied as a hard coat on top of a polyethylene terephthalate (PET) film, this nanocomposite has a short UV‐cure time and the cured coat has an enhanced thermal decomposition temperature (Td), 89–90% transparency, increased hardness up to 3H, better adhesion up to 4B, and a flat surface with a root mean square roughness of 2–4 nm. The preparation as well as the characterization of the constituting species and the final hybrid are described in detail. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3985–3993, 2007
Preparation and characterization of poly(vinyl chloride)/virgin and treated sisal fiber composites
Authors: Djidjelli Hocine , Boukerrou A. , Founas R. , Rabouhi A. , Kaci M. , Farenc J. , Martinez‐Vega Juan‐Jorge , Benachour Djafer 
Published: December 2006

AbstractMechanical property changes, thermal stability, and water absorption capacity of poly(vinyl chloride) (PVC)/sisal fiber composites were assessed with respect to the effect of maleic anhydride chemical treatments of the sisal fiber, for five different sisal fiber contents, varying from 0 to 30% by weight in the composite. The composites prepared with the untreated sisal exhibited higher tensile modulus and hardness than the unloaded resin, while elongation and tensile strength were reduced. The deterioration in the mechanical properties of PVC blended with sisal fiber is attributed to the presence of moisture, interfacial defects at the fiber and polymer interface, and fiber dispersion in the PVC matrix. The amount of absorbed water is a function of the amount of fiber in the composite (F0 = 0 phr, F5 = 0.77 phr, and F20 = 4.83 phr). The comparison of the results of characterization of F5, F20, and F30 formulations prepared with the untreated fibers and the treated ones showed a reduction in absorbed water after the chemical treatment of fiber with maleic anhydride (F0 = 0 phr, F5 = 0.28 phr, and F20 = 2.99 phr), thus improving the mechanical properties of composites prepared with the treated sisal. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3630–3636, 2007
Melt transesterification of bisphenol acetophenone–polycarbonate: A kinetic study
Authors: Godinez C. , Lozano L. J. 
Published: December 2006

AbstractThis article deals with the development of kinetic parameters for bisphenol acetophenone–polycarbonate made by melt transesterification with diphenyl carbonate. The understanding of the influence of borosilicate glass of the reactor construction materials on the accuracy of the kinetic data is reported. During the development of analytical methods, the use of high performance liquid chromatography‐mass spectrometry (HPLC‐MS) was proven to be a valid tool to determine the oligomers existing in the reaction mixture. Accurate kinetics parameters were obtained by elimination of the interference of the construction materials. We provide the rate expressions, kinetic parameters [forward reaction frequency factor = 2.456 × 1013 ± 0.01 (cm3/mol)2/min, forward reaction activation energy = 45.69 ± 0.2 kJ/mol, reverse reaction frequency factor = 2.068 × 1014 ± 0.01 (cm3/mol)2/min, and reverse reaction activation energy = 56.37 ± 0.1 kJ/mol], and equilibrium constants at various temperatures. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4072–4079, 2007
Preparation of rubber composites from ground tire rubber reinforced with waste‐tire fiber through mechanical milling
Authors: Zhang Xin‐Xing , Lu Can‐Hui , Liang Mei 
Published: December 2006

AbstractComposites made from ground tire rubber (GTR) and waste fiber produced in tire reclamation were prepared by mechanical milling. The effects of the fiber content, pan milling, and fiber orientation on the mechanical properties of the composites were investigated. The results showed that the stress‐induced mechanochemical devulcanization of waste rubber and the reinforcement of devulcanized waste rubber with waste‐tire fibers could be achieved through comilling. For a comilled system, the tensile strength and elongation at break of revulcanized GTR/fiber composites reached maximum values of 9.6 MPa and 215.9%, respectively, with 5 wt % fiber. Compared with those of a composite prepared in a conventional mixing manner, the mechanical properties were greatly improved by comilling. Oxygen‐containing groups on the surface of GTR particles, which were produced during pan milling, increased interfacial interactions between GTR and waste fibers. The fiber‐filled composites showed anisotropy in the stress–strain properties because of preferential orientation of the short fibers along the roll‐milling direction (longitudinal), and the adhesion between the fiber and rubber matrix was improved by the comilling of the fiber with waste rubber. The proposed process provides an economical and ecologically sound method for tire‐rubber recycling. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4087–4094, 2007
Preparation and properties of polysulfone–clay composite membranes
Authors: Monticelli Orietta , Bottino Aldo , Scandale Ivan , Capannelli Gustavo , Russo Saverio 
Published: December 2006

AbstractPorous membranes and dense films were prepared from polysulfone solutions in N‐methyl‐2‐pyrrolidone (NMP) containing different types and amounts of clay. Commercial clays supplied by Southern Clay, either unmodified (Cloisite Na) or organically modified (Cloisite 30B and Cloisite 93A), were used. The clay behavior in the organic solvent was dependent on the presence and type of the organic compatibilizer: Cloisite containing Na ions did not swell in NMP, whereas those with the organic compatibilizer swelled, though to a different degree. Electron microscopy observations were made to examine the clay dispersion in the membrane structure. At variance with Cloisite Na and Cloisite 93A formed microaggregates, Cloisite 30B yielded nanostructures composed of both single sheets and well‐ordered multilayer silicate clusters, which were characterized by an interlayer distance higher than that of the neat clay. The increase in the distance between the layers of Cloisite 30B was related to the formation of intercalated nanocomposites, whereas the presence of single sheets well distributed in the polymer matrix supported the occurrence of delaminated nanocomposites. The intercalation of the polymer into clay layers was confirmed with wide‐angle X‐ray diffractometry. The addition of Cloisite 30B to the casting solution influenced the phase‐separation process in the coagulation bath. Therefore, by the variation of the layered‐silicate concentration in the casting solution, membranes with different morphological structures and ultrafiltration properties were obtained. Cloisite 30B was also found to improve the wettability and mechanical properties of dense films. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3637–3644, 2007
Effect of ethylene glycidyl methacrylate compatibilizer on the structure and mechanical properties of clay nanocomposites modified with ethylene vinyl acetate copolymer
Authors: Guduri B. R. , Luyt A. S. 
Published: December 2006

AbstractThe structure and mechanical properties of clay modified with ethylene vinyl acetate copolymer in the presence of ethylene glycidyl methacrylate (EGMA) were investigated as a function of compatibilizer and clay contents. The structure and properties were determined by X‐ray diffraction, transmission electron microscopy, differential scanning calorimetry, and thermogravimetric analysis (TGA). The presence of EGMA caused strong exfoliation of the clay in the polymer matrix, although at higher clay contents, some clay layers still existed. The more effective exfoliation, however, did not seem to substantially influence the tensile properties of the nanocomposites because the EGMA itself had a much stronger influence, which overshadowed any possible influence that the EGMA–clay interaction may have had on these properties. The thermal stability of the nanocomposites (as studied by TGA) improved in the presence of EGMA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4095–4101, 2007
Effect of filler content and size on the properties of ethylene vinyl acetate copolymer–wood fiber composites
Authors: Dikobe D. G. , Luyt A. S. 
Published: December 2006

AbstractIn this study, the main focus was on the effect of wood fiber (WF) content and particle size on the morphology and mechanical, thermal, and water‐absorption properties of uncompatibilized and ethylene glycidyl methacrylate copolymer (EGMA) compatibilized ethylene vinyl acetate copolymer–WF composites. For uncompatibilized composites, the tensile strength decreased with increasing WF content, whereas for compatibilized composites, the tensile strength initially decreased, but it increased for composites containing more than 5% WF. Small‐WF‐particle‐containing composites had higher tensile strengths than composites containing larger WF particles, both in the presence and absence of EGMA. WF particle size did not seem to have much influence on the degradation behavior of the composites, whereas water absorption by the composites seemed to be higher in composites with smaller particle sizes for both compatibilized and uncompatibilized composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3645–3654, 2007
Performance characterization of composite materials based on recycled high‐density polyethylene and ground tire rubber reinforced with short glass fibers for structural applications
Authors: Shojaei A. , Yousefian H. , Saharkhiz S. 
Published: December 2006

AbstractThis study addresses the issue of using recycled materials to obtain low‐cost structural products for practical applications. Through the use and re‐extrusion of virgin high‐density polyethylene (HDPE), the effects of the degradation level of HDPE as a matrix phase on its mechanical properties and the mechanical performance of composites produced with the degraded polyethylene have been examined. The degradation level of HDPE caused by re‐extrusion has been evaluated by the measurement of the melt flow index and mechanical properties of virgin and degraded HDPEs. The results indicate that the modulus and strength of HDPE significantly increase with the addition of polypropylene filled with 30 wt % glass fiber [PP–GF(30)] without any other compatibilizer. However, the final properties of composites with specified glass‐fiber contents are dependent on the degradation level of the matrix phase. In addition, the role of ground tire rubber (GTR) in HDPE/PP–GF(30) systems has been examined by the preparation of composites with various GTR contents without any treatments. The results show that the presence of GTR in the final product results in lower stiffness because of its role as a soft filler, but the elongation of the product increases slightly. Furthermore, GTR does not produce any improvement in the impact properties, probably because of the low interfacial adhesion with the matrix phase; therefore, its content should be kept low in the final composition. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Functional finishing by using atmospheric pressure plasma: Grafting of PET nonwoven fabric
Authors: Shin Younsook , Son Kyunghee , Yoo Dong Il 
Published: December 2006

AbstractPoly (ethylene terephtalate) (PET) nonwoven fabric was treated with He/O2 plasma to produce peroxides and grafted with acrylic acid (AA) for introducing carboxyl groups onto PET surface. The graft yield increased with AA concentration from 1.5M to 2.5M, and then decreased with further increase in AA concentration. Graft yield increased with sodium pyrosulfite (SPS) concentration from 0.005M to 0.02M, and then decreased with further increase of SPS concentration. X‐ray photoelectron spectroscopy results indicated that both of plasma treatment and AA grafting increased oxygen content and decreased carbon content on the PET nonwoven fabric surface. The grafted PET nonwoven fabric showed increase in moisture regain and dye uptake. And drastic increase in wettability was observed after grafting. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3655–3659, 2007
The effect of zinc oxide addition on the compatibilization efficiency of maleic anhydride grafted high‐density polyethylene compatibilizer for high‐density polyethylene/polyamide 6 blends
Authors: Chatreenuwat Benjamaad , Nithitanakul Manit , Grady Brian P. 
Published: December 2006

AbstractA high‐density polyethylene with grafted maleic anhydride units has been investigated as a compatibilizer for high‐density polyethylene with polyamide 6. The material acts as an effective compatibilizer, causing a marked reduction in dispersed phase size as well as an increase in tensile strength and toughness. Compatibilizer also affects the glass‐transition temperature, crystallization kinetics, and amount of crystalline material for certain blend compositions. The addition of zinc cations, which are effective in increasing ethylene‐acid copolymer compatibilizer performance in low‐density polyethylene/polyamide blends, has little, if any, effect on compatibilizer performance in these high‐density polyethylene/polyamide blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3871–3881, 2007
Kinetics of thermal degradation of poly(p‐phenylene benzobisoxazole)
Authors: Lin Heng , Zhuang Qixin , Cheng Jianjun , Liu Zitao , Han Zhewen 
Published: December 2006

AbstractThe kinetics of thermal degradation of poly (p‐phenylen benzobisoxazole) (PBO) were studied by thermogravimetric analysis (TG) in dynamic nitrogen gas at four different heating rates: 5, 10, 15, 20°C/min. The activation energy calculated by Kissinger Method was 352.19 kJ/mol, and the mean value of activation energies evaluated by Flynn‐Wall‐Ozawa Method was 338.32 kJ/mol. The degradation kinetic model of PBO followed the mechanism of random scission of weak bonds of PBO molecule and impact of the active groups obtained from the broken bonds, Mampel Power equation with integral form G(α) = α3/2 and differential form
$ f(\alpha)={2\over 3}\alpha^{-1/2} $. And the mathematical equation of kinetic compensation effect was ln A = 0.1365 Ea − 1.4102. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3675–3679, 2007
Influence of an antimicrobial treatment on the strength properties of polyamide/elastane weft‐knitted fabric
Authors: Mihailovic Tatjana , Asanovic Koviljka , Simovic Ljiljana , Skundric Petar 
Published: December 2006

AbstractPolyamide/elastane weft‐knitted fabric, as a suitable compression material, was treated with gentamicin sulfate and a natural antimicrobial preparation of the autochthonous essential oil of Picea abies. The antimicrobial bioactivity of the treated fabric in vitro was tested for different groups of bacteria and a fungus (Staphylococcus aureus, Escherichia coli, Klabsiella, and Candida albicans). The results of the experiment showed that the antimicrobial‐treated knitted fabric expressed a wide range of bactericidal, fungicidal, and bacteriostatic activity versus the various groups of microorganisms. The influence of the antimicrobial treatments on the tensile strength and elongation, tear strength and elongation, stiffness, and elasticity of the chosen test material was also examined. These properties of the fabric were changed after the antimicrobial treatments. Both the tensile strength and tear strength increased about 14% after the treatment. The scope of the experiment also included the testing of the compression distribution at the skin/knitted fabric interface on the legs of human test subjects. Pressure generated by the application of the knitted fabric on the leg surface increased in correlation with a decrease in the leg circumference. On the basis of these observations, it was concluded that the knitted fabric could be used as a compression textile before and after the treatment. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4012–4019, 2007
Amelioration of acrylonitrile–butadiene copolymer properties using natural rubber graft p‐aminophenol
Authors: El‐Wakil A. A. 
Published: December 2006

AbstractA two‐roll mill machine was used for the grafting of p‐aminophenol (pAP) onto natural rubber (NR). The prepared NR graft p‐aminphenol (NR‐g‐pAP) was characterized by 1H NMR and IR spectroscopy techniques. The goal of this article is to study the effect of commercial antioxidants, N‐phenyl‐N′‐(1,3‐dimethylbutyl)‐p‐phenylenediamine (6PPD) and N‐phenyl‐N′‐isopropyl‐p‐phenylenediamine (IPPD), and the prepared NR‐g‐pAP, on the mechanical properties of acrylonitrile–butadiene (NBR) vulcanizates, the fluid compatibility of NBR vulcanizates, the hydraulic brake and clutch fluid dot, the diffusion out for NBR vulcanizate components, and the compression recovery of NBR vulcanizates. This study indicates that the NBR copolymer vulcanizate which contains the prepared NR‐g‐pAP has good protection against mechanical stress and the diffusion out of NBR vulcanizate components. The 6PPD and the prepared NR‐g‐pAP ameliorates the fluid compatibility of the oil seals, which is based on NBR as elastomer, and the hydraulic brake and clutch fluid dot. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Reverse atom transfer radical polymerization of MMA via immobilized catalysts in imidazolium ionic liquids
Authors: Li Najun , Lu Jianmei , Xu Qingfeng , Xia Xuewei , Wang Lihua 
Published: December 2006

AbstractReverse atom transfer radical polymerization (RATRP) of methyl methacrylate (MMA) employing immobilized catalyst was approached at 50 and 60°C in [C8mim]PF6, and compared with the polymerization of MMA DMF as solvent. Other ionic liquids, [C6mim]BF4, [C8mim]BF4, and [C12mim]BF4, were used as solvents to perform the RATRP of MMA. By comparison, we found that the [C8mim]PF6 was the best solvent in this immobilized catalyst system and the polymerization was best controlled. In addition, the immobilized catalyst spherules can easily separate from the reaction mixture, which avoids the prevalent problem of the catalyst residual in RATRP and also gives us a possibility to recycle the catalyst system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3915–3919, 2007