bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting the effect of dissolved carbon dioxide on the glass transition temperature of poly(acrylic acid)
Authors: Cao Gui‐Ping , Liu Tao , Roberts George W. 
Published: October 2009

AbstractThe morphology and size of poly(acrylic acid) (PAA) particles produced by precipitation polymerization in supercritical CO2 (scCO2) depends on the glass transition temperature (Tg) of the polymer at reaction conditions. In this study, the use of the Sanchez–Lacombe equation of state (SL‐EOS), in conjunction with Chow's equation, to predict the effect of CO2 pressure on the Tg of PAA was evaluated. Characteristic parameters for PAA were determined by fitting density data. Characteristic parameters for CO2 were determined by fitting density data in the supercritical region. When the SL‐EOS was used in a purely predictive mode, with a binary interaction parameter (ψ) of 1, the solubility of CO2 in PAA was underestimated and Tg was overestimated, although the trend of Tg with CO2 pressure was captured. When was determined by fitting the SL‐EOS to the measured sorption of scCO2 in PAA, the calculated Tg's agreed very well with measured values. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Anionic polymerization of 1,3‐cyclohexadiene: Addition of poly(1,3‐cyclohexadienyl)lithium to fullerene‐C60
Authors: Natori Itaru , Natori Shizue 
Published: October 2009

AbstractThe addition of poly(1,3‐cyclohexadiene) (PCHD) carbanion to fullerene‐C60 (C60) was examined using poly(1,3‐cyclohexadienyl)lithium (PCHDLi), PCHDLi/1,4‐diazabicyclo[2,2,2]octane (DABCO), and PCHDLi/N,N,N′,N′‐tetramethylethylenediamine (TMEDA). The reactivity of PCHD carbanions was in the order of PCHDLi > PCHDLi/DABCO > PCHDLi/TMEDA, regardless of the polymer main chain structure. PCHDLi, PCHDLi/DABCO, and PCHDLi/TMEDA in toluene formed σ‐structures, σ‐ and π‐structures, and π‐structures, respectively. The degree of localization on the terminal carbanion was a main factor for control of this addition reaction. In addition, all 1,2‐cyclohexadiene (1,2‐CHD) unit sequences contributed to preventing the addition reaction. That is, large steric hindrance of the polymer main chain was another important factor to control the addition reaction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Nanostructures and thermomechanical properties of epoxy thermosets containing reactive diblock copolymer
Authors: Xu Zhiguang , Hameed Nishar , Guo Qipeng , Mai Yiu‐Wing 
Published: October 2009

AbstractPolystyrene‐block‐poly(glycidyl methacrylate) reactive diblock copolymer (PS‐b‐PGMA) was synthesized via atom transfer radical polymerization (ATRP). The diblock copolymer was characterized using nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). The cured epoxy thermosets with 10–20 nm PS particles were prepared by blending the diblock copolymer with epoxy resin. The nanostructures were examined by means of transmission electronic microscopy (TEM) and small angle X‐ray scattering (SAXS). The formation of the nanostructures was caused by the reaction‐induced microphase separation mechanism. It is significant that the glass transition temperatures (Tgs) of these epoxy thermosets were increased by the addition of PS‐b‐PGMA reactive block copolymer as revealed by both differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Incorporating amylopectin in poly(lactic acid) by melt blending using poly(ethylene‐co‐vinyl alcohol) as a thermoplastic carrier. (I) morphological characterization
Authors: Nordqvist D. , Sanchez‐García Maria D. , Hedenqvist Mikael S. , Lagaron Jose M. 
Published: October 2009

AbstractIn this study, the possibility of using a biodegradable grade of thermoplastic poly(ethylene‐co‐vinyl alcohol) with high (71 mol %) vinyl alcohol (EVOH‐29), as a carrier to incorporate the renewable and biodegradable component amylopectin (AP) into poly(lactic acid) (PLA) through melt blending, was investigated. The effect of using a plasticizer/compatibilizer (glycerol) in the blend systems was also investigated. In a first step, the EVOH/AP blends were produced and thereafter, in a second step, these were mixed with PLA. In this first study, the blend morphology was investigated using optical microscopy, scanning electron microscopy and Raman imaging spectroscopy and the thermal properties were measured by differential scanning calorimetry. Despite the fact that EVOH and AP are both highly polar, their blends were immiscible. Still, the blends exhibited an excellent phase dispersion on a micron level, which was enhanced further by the addition of glycerol. A good phase dispersion was finally observed by incorporation of the latter blends in the PLA matrix, suggesting that the proposed blending route can be successfully applied for these systems. Finally, the Differential scanning calorimetry (DSC) data showed that the melting point of EVOH dropped in the EVOH/AP blends, but the properties of the PLA phase was still relatively unaffected as a result of blending with the above components. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The fracture mechanism of polylactic acid resin and the improving mechanism of its toughness by addition of acrylic modifier
Authors: Ito Masakazu , Abe Satomi , Ishikawa Masaru 
Published: October 2009

AbstractThe fracture mechanism of polylactic acid (PLA) resin and the improving mechanism of its toughness by addition of an acrylic modifier were examined. Plane strain compression testing of PLA clearly showed strong softening after yielding. Because the stress for craze nucleation of PLA was close to the yield stress, brittle fractures resulted. The addition of an acrylic modifier to the PLA significantly lowered the yield stress and formed many voids. The release of the strain constraint because of the formation of many voids and the decrease of yield stress resulted in the relaxation of stress concentration, and the toughness was improved. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Vinylester resin‐clay hybrids using various intercalating agents
Authors: Agag Tarek , Akelah Ahmed , Abdelwahab Mohamed , Takeichi Tsutomu , Muto Hiroyuki 
Published: October 2009

AbstractVinylester resin‐clay hybrids were prepared by the mixing different types of organically‐modified montmorillonite (OMMT) with vinylester resin (VER) prepolymer, followed by thermal polymerization. VER prepolymer was synthesized from the reaction of diglycidylether of bisphenol‐A (DGEBA) with acrylic acid. Various types of organic ammonium salts have been used as intercalating agents for montmorillonite, including N,N‐dimethyl‐N‐(4‐vinylbenzyl)stearyl ammonium chloride (VSA), N‐allyl‐N,N‐dimethyl‐stearyl ammonium chloride (ASA) and N,N‐dimethyl‐stearyl ammonium chloride (SA). The dispersion of OMMT into VER matrix was studied by XRD, which indicates the dependence of the morphology mainly on the OMMT content. UV–vis spectra of the hybrids were used to give a quantitative value of the effect of OMMT content on the transparency of VER/OMMT hybrid films. Also, the Vickers test has been performed to study the effect of OMMT content on the surface hardness of the hybrid films. In addition, the thermal properties of the hybrids have been characterized by measuring the softening points and thermogravimetric analyses of the hybrids in comparison with the pure resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
New generation polymeric nanospheres for lysozyme adsorption
Authors: Akgöl Sinan , Öztürk Nevra , Denizli Adil 
Published: October 2009

AbstractNovel hydrophobic nanospheres with an average size of 100 nm utilizing N‐methacryloyl‐(l)‐tryptophan methyl ester (MAT) as a hydrophobic monomer were prepared by surfactant free emulsion polymerization of 2‐hydroxyethyl methacrylate (HEMA) and MAT. MAT was synthesized using methacryloyl chloride and l‐tryptophan methyl ester. Specific surface area of the nonporous nanospheres was found to be 1914 m2/g. Poly(HEMA–MAT) nanospheres were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Average particle size, size distribution, and surface charge measurements were also performed. Elemental analysis of MAT for nitrogen was estimated as 1.95 mmol/g polymer. Then, poly(HEMA–MAT) nanospheres were used in the adsorption of lysozyme in batch system. Using an optimized adsorption protocol, a very high loading of 1075 mg lysozyme/g nanosphere was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. It was observed that enzyme could be repeatedly adsorbed and desorbed without significant loss in adsorption amount or enzyme activity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis of stimuli‐responsive star‐like copolymer H20‐PNIPAm‐r‐PEGMA via the ATRP copolymerization technique and its micellization in aqueous solution
Authors: Di Chunfeng , Jiang Xuesong , Yin Jie 
Published: October 2009

AbstractA series of novel star‐like copolymers H20‐poly(N‐isopropylacrylamide)‐random‐poly(poly(ethylene glycol) methyl ether methacrylate) (H20‐PNIPAm‐r‐PEGMA), which could respond to both temperature and ionic strength stimuli in aqueous solution were synthesized by atom transfer radical polymerization. Stimuli‐response of these copolymers in aqueous solution was characterized by dynamic laser scattering (DLS), 1H‐NMR and turbidity. In aqueous solution, these star‐like copolymers exhibited response to temperature and ionic strength with tunable low‐critical solution temperature (LCST) from 32 to 100°C. The LCST values of copolymers increased with increasing PEGMA contents, while decreased with increasing ionic strength. An interesting phenomenon, which should be a unique character of star‐like copolymer, was observed by the turbidity test of copolymer 1160. The addition of sodium chloride and increase of concentration can let copolymer 1160 behave normally, which was further confirmed by atomic force microscopy and DLS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study on the influence of thermal characteristics of hyperbranched polyurethane phase change materials for energy storage
Authors: Cao Qi , Liao Li , Xu Haili 
Published: October 2009

AbstractA series of hyperbranched polyurethane (HB‐PU) phase change induced energy storage materials were prepared by polyethylene glycol (PEG), methylene diphenyl 4,4′‐diisocyanate (MDI), and hyperbranched polyester polyalcohol via a two‐step process. The influence of thermal characteristics of HB‐PU was investigated using differential scanning calorimetry (DSC) and wide‐angle X‐ray diffraction (WAXD). It has been found that the thermal characteristics of HB‐PU are affected by some factors. Such as the molecular weight and content of soft segment, once the Mn of PEG soft segments is larger than the critical Mn (2000 g/mol), both the phase change enthalpy and temperature increase as Mn of PEG soft segment and soft segment content (SSC) increase. The influence of the microstructure of hard segment originates from diisocyanate and hyperbranched polyester polyalcohol, HB‐PUs with regular microstructure and lower generation of hyperbranched polyester polyalcohol have high energy storage capability. Furthermore, the conditions of measurement affect the thermal characteristics of materials. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Reactive compatibilization of polymer blends by γ‐irradiation: Influence of the order of processing steps
Authors: Sonnier Rodolphe , Massardier Valérie , Clerc Laurent , Lopez‐Cuesta Jose Marie , Bergeret Anne 
Published: October 2009

AbstractResults concerning γ‐irradiation of polymer blends such as HDPE/ground tire rubber (GTR) and PP/HDPE are reported in this article with a special emphasis on the order of processing steps. Irradiation dose varied in the range 0–100 kGy. The two first polymers (HDPE and rubber) are preferentially crosslinked under γ irradiation while PP undergoes chain scission. Mechanical tests and differential scanning calorimetry (DSC) analysis show that the efficiency of the reactive compatibilization by γ irradiation depends greatly on the chronology of γ‐irradiation and injection‐molding steps. Electron spin resonance (ESR) results reveal that numerous radicals remain trapped in the materials after γ‐irradiation even after a long time. Then the effect of irradiation on material properties is different if polymers are melted after irradiation or not. Crosslinking and chain scission are not affected in an equivalent way by the order of processing steps. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study on thermal enhancement mechanism of POSS‐containing hybrid nanocomposites and relationship between thermal properties and their molecular structure
Authors: Feng Yan , Jia Yong , Guang Shanyi , Xu Hongyao 
Published: October 2009

AbstractIn this study, a series of poly(4‐acetoxystyrene) (PAS)‐octavinyl polyhedral oligomeric silsesquioxane (POSS) blends and the polystyrene (PS)‐octavinyl POSS blends were prepared by the solution‐blending method and characterized with Fourier transform infrared (FTIR), X‐ray diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques. The results show that the glass‐transition temperature (Tg) of the PAS‐POSS blends increases at a relatively low POSS content and then decreases at a relatively high POSS content. POSS can effectively improve the thermal stability of the PAS‐POSS blends at low POSS content, and Tg of PAS‐POSS blends decreases with the increase in POSS content at relatively high POSS content. However, the Tg of the PS‐POSS blends persistently decreases even at very low POSS content. Tg change mechanism was investigated in detail by XRD, TEM, and FTIR spectra. The influence mechanism of POSS content and dispersion in composites, and parent polymer structure on thermal properties of the blends was investigated in detail. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Enhanced corrosion protective coating based on conducting polyaniline/zinc nanocomposite
Authors: Olad Ali , Rasouli Haleh 
Published: October 2009

AbstractConducting polyaniline (PANI) is being explored as promising material for protection of metals against corrosion. It has the possibility of making smart coatings on metals, which can prevent corrosion even in scratched areas where bare metal surface is exposed to the aggressive environment. However, PANI coatings have poor barrier and mechanical properties. The barrier property of coatings can be enhanced by the addition of appropriate filler particles. Also it has been demonstrated that nanoparticulate fillers give much better barrier properties even at lower concentrations. In this study, the effect of zinc nanoparticles on the anticorrosive property of PANI coating on iron samples has been investigated. The PANI/Zn nanocomposite was synthesized by in situ polymerization of aniline in the presence of Zn nanoparticles. The nanocomposite was characterized by using FTIR, conductivity measurement, cyclic voltammetry, and AFM techniques. Results showed that PANI/Zn nanocomposite coating has improved corrosion protection effect when compared with pure PANI coating. The corrosion current of PANI/Zn coated samples were found to be much lower than that of pure PANI coated samples. The results were referred to the good barrier properties of Zn nanoparticles and improvement in electrochemical corrosion protection of PANI coating in the presence of Zn nanoparticles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and electrochemical capacitance of poly(pyrrole‐co‐aniline)
Authors: Zhang Ai‐Qin , Wang Li‐Zhen , Zhang Lin‐Sen , Zhang Yong 
Published: October 2009

AbstractThe copolymer of pyrrole and aniline, poly(pyrrole‐co‐aniline), has been prepared by chemical oxidation of corresponding monomer mixtures with ammonium peroxysulfate. Techniques of FTIR, SEM‐EDS, and BET surface area measurement were used to characterize the structure and morphology of the copolymer. The electrochemical properties of the copolymer were investigated by cyclic voltammetry, galvanostatic charge‐discharge, and electrochemical impedance spectroscopy. The results indicated that poly(pyrrole‐co‐aniline) was about 100–300 nm in diameter and showed better electrochemical capacitive performance than polypyrrole and polyaniline. The specific capacitance of the copolymer electrode was 827 F/g at a current of 8 mA/cm2 in 1 mol/L Na2SO4 electrolyte. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis of poly(butylene succinate‐co‐butylene terephthalate) (PBST) copolyesters with high molecular weights via direct esterification and polycondensation
Authors: Luo Shengli , Li Faxue , Yu Jianyong , Cao Amin 
Published: October 2009

AbstractIn this article, biodegradable poly(butylene succinate‐co‐butylene terephthalate) (PBST) copolyesters with high molecular weights were synthesized by direct esterification and polycondensation route. The reaction conditions and catalytic systems were investigated in detail. Through balancing the reaction efficiency and the costs of reactants, the proper molar ratio of diol to diacid was determined. Titanium tetraisopropoxide (TTiPO) was found to be an effective catalyst both in esterification and polycondensation reaction, and its content was optimized based on the esterification ratio and amount of formed by‐products. The complex reaction was determined to be the dominant catalytic reaction mechanism. By importing the additives of metal oxides coupled with TTiPO, the weight‐average molecular weights of PBST increased sharply from 8.51 × 104 to 14.38 × 104, manifesting the additives promoted the polymerization reaction greatly. The enhancement of carbonyl polarization and provision of suitable reaction space arose from the metal oxides were the reasons for promoting the polymerization reaction. With respect to thermal properties, the same melting point and heat of fusion were found, while thermal stability increased with the import of additives. The result was prone to be interpreted by the higher molecular weights of PBST in the presence of additives. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The mechanical properties and thermal performances of polypropylene with a novel intumescent flame retardant
Authors: Zhang Qingbo , Xing Haitao , Sun Caiying , Xiang Haiwang , Jiang Dawei , Qin Linlin 
Published: October 2009

AbstractA novel intumescent flame retardant: tetra‐spirophosphoryl‐benzoguanamine (TSPB) containing three constituents was used as a new flame retardant for polypropylene to prepare flame‐retardant materials, whose flammability and thermal behavior were studied by the limited oxygen index (LOI), thermogravimetric analysis (TGA), in addition whose mechanical properties were investigated in this work. It was found that when the addition of TSPB was 25 wt %, the LOI value of the PP could achieve to 29.5 and pass the UL‐94 V‐0 rating test. The TGA data showed that TSPB could enhance the thermal stability of PP and effectively increase the char residue formation. The mechanical performance test showed that the addition of TSPB improve the mechanical performances of PP to some extent. Thus, the trinity intumescent flame retardant TSPB is good to modify PP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Patterned conductive polyaniline films fabricated using lithography and in situ polymerization
Authors: Liu Cheng‐Dar , Wu Sheng‐Yen , Han Jin‐Lin , Hsieh Kuo‐Huang 
Published: October 2009

AbstractIn this article, we describe a novel bottom‐up technique for the preparation of transparent conductive films of polyaniline (PANI). A UV‐curable photoresist was formulated containing an acrylate‐endcapped urethane oligomer [UA(PPG400)], acrylic acid, a photoinitiator, and a reactive diluent (tripropylene glycol diacrylate), and the lithography techniques were used to pattern the structure with line widths/spaces of 100 μm/100 μm, 10 μm/10 μm, and 5 μm/5 μm on a polyethylene terephthalate substrate. The carboxylic acid units on the surface of the patterned photoresist interacted with the aniline monomer units to form anilinium complexes; using ammonium persulfate as a chemical oxidant, we then synthesized a layer of conductive PANI on the surface of the patterned resist through in situ polymerization. The optimal conductivity of the PANI conductive film was ca. 10 S/cm. The thin film was characterized, and its physical properties investigated using Fourier transform infrared spectroscopy, UV–Vis spectroscopy, differential scanning calorimetry, optical and atomic force microscopy, and four‐point probe conductivity measurements. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Dyeing and deodorizing properties of cotton, silk, wool fabrics dyed with Amur Corktree, Dryopteris crassirhizoma, Chrysanthemum boreale, Artemisia extracts
Authors: Lee Young‐Hee , Hwang Eun‐Kyung , Jung Young–Jin , Do Seong‐Kook , Kim Han‐Do 
Published: October 2009

AbstractThis study used four kinds of natural colorant solutions extracted from Amur Corktree, Dryopteris crassirhizoma, Chrysanthemum boreale, Artemisia using water at 90°C for 90 min with a liquor ratio (solid natural colorant material/solvent water, weight ratio) of 1/10. The dyeing, color fastness, deodorizing properties of cotton, silk, wool fabrics dyed with natural colorant extracts were compared. These properties were found to be significantly dependent on the extract concentration, colorant structure, fabric type. Color fastness (light, water, perspiration fastness) ranged between second and fifth grades and deodorizing performance of fabrics dyed with various natural colorant extracts between 34 and 99%. It is worth noting that the use of natural colorants notably enhanced the deodorizing performance. Wool fabrics showed the highest performance increase at 98–99%, followed by silk and cotton. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A novel soluble PANI/TPU composite doped with inorganic and organic compound acid
Authors: Wang Jiliang , Yang Wanqing , Tong Pengcheng , Lei Jingxin 
Published: October 2009

AbstractA series of novel soluble and thermoplastic polyurethane/polyaniline (TPU/PANI) composites doped with a compound acid, which was composed of an organic acid (p‐toluene sulfonic acid) and an inorganic acid (phosphoric acid), were successfully prepared by in situ polymerization. The effect of aniline (ANI) content, ratio of organic acid/inorganic acid, and different preparation methods on the conductivity of the TPU/PANI composites were investigated by using conductivity measurement. Lithium bisoxalato borate (LiBOB) was added to the prepared in situ TPU/PANI to coordinate with the ether oxygen groups originating from the soft molecular chains of TPU, and thus the conductivity of the composites was further enhanced. The molecular structure, thermal properties, and morphology of the TPU/PANI composites were studied by UV–visible spectroscopy, differential scanning calorimetry, and scanning electron microscopy, respectively. The results show that the in situ TPU/PANI composites doped with the compound acid can be easily dissolved in normal solvents such as dimethylformamide (DMF) and 1,4‐dioxane. The conductivity of the TPU/PANI composites increases with the increase of the ANI content, in the ANI content range of 0–20 wt %; however, the conductivity of the composites reduces with further increment of ANI content. The conductivity of the TPU/PANI composites prepared by in situ polymerization is about two orders of magnitude higher than that prepared by solution blending method. LiBOB can endow the in situ TPU/PANI composites with an ionic conductivity. The dependence of the conductivity on temperature is in good accordance with the Arrhenius equation in the temperature range of 20–80°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010