bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phase behavior of binary and ternary blends of poly(styrene‐co‐methacrylic acid), poly(styrene‐co‐4‐vinylpyridine), and poly(2,6‐dimethyl‐1,4‐phenylene oxide)
Authors: Benabdelghani Z. , Djadoun S. , Etxeberria A. , J Iruin J. , Uriarte C. 
Published: December 2007

AbstractPoly(styrene‐co‐methacrylic acid) (PSMA) and poly(styrene‐co‐4‐vinylpyridine) (PS4VP) of different compositions were prepared and characterized. The phase behavior of these copolymers as binary PSMA/PS4VP mixtures or with poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) as PPO/PSMA or PPO/PS4VP and PPO/PSMA/PS4VP ternary blends was investigated by differential scanning calorimetry (DSC). This study showed that PPO was miscible with PS4VP containing up to 15 mol % 4‐vinylpyridine (4VP) but immiscible with PS4VP‐30 (where the number following the hyphen refers to the percentage 4VP in the polymer) and PSMA‐20 (where the number following the hyphen refers to the percentage methacrylic acid in the polymer) over the entire composition range. To examine the morphology of the immiscible blends, scanning electron microscopy was used. Because of the hydrogen‐bonding specific interactions that occurred between the carboxylic groups of PSMA and the pyridine groups of PS4VP, chloroform solutions of PSMA‐20 and PS4VP‐15 formed interpolymer complexes. The obtained glass‐transition temperatures (Tg's) of the PSMA‐20/PS4VP‐15 complexes were found to be higher than those calculated from the additivity rule. Although, depending on the content of 4VP, the shape of the Tg of the PPO/PS4VP blends changed from concave to S‐shaped in the case of the miscible blends, two Tg were observed with each PPO/PS4VP‐30 and PPO/PS4VP‐40 blend. The thermal stability of the PSMA‐20/PS4VP‐15 interpolymer complexes was studied by thermogravimetry. On the basis of the obtained results, the phase behavior of the ternary PPO/PSMA‐20/PS4VP‐15 blends was investigated by DSC. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Study on superabsorbent composites. XVIII. Preparation, characterization, and property evaluation of poly(acrylic acid‐co‐acrylamide)/organomontmorillonite/sodium humate superabsorbent composites
Authors: Zheng Yian , Wang Aiqin 
Published: December 2007

AbstractA series of novel multifunctional poly (acrylic acid‐co‐acrylamide) (PAA‐AM)/organomontmorillonite (O‐MMT)/sodium humate (SH) superabsorbent composites were synthesized by the graft copolymerization reaction of partially neutralized acrylic acid and acrylamide on O‐MMT micropowder and SH with N,N′‐methylene bisacrylamide as a crosslinker and ammonium persulfate as an initiator in an aqueous solution. The superabsorbent composites were characterized by means of Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The effect of the relative weight ratio of SH to O‐MMT on the water absorbency was studied, and the results indicated that the best water absorbency of 591 g/g in distilled water was obtained when an O‐MMT content of 20 wt % and an SH content of 30 wt % were incorporated. The superabsorbent composite possessed a good capacity for water retention; even after 30 days, 24.4 wt % of water could still be saved by the sand soil containing 1.0 wt % superabsorbent composite. The results from this study show that the water absorbency of a superabsorbent composite is improved by the simultaneous introduction of O‐MMT and SH into a PAA‐AM network in comparison with the incorporation of only O‐MMT or SH. Also, in comparison with PAA‐AM/MMT/SH, an appropriate amount of O‐MMT can benefit the developed composites with respect to their water absorbency, salt resistance, and capacity for water retention in sand soil. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Aqueous dispersion polymerization of acrylamide with quaternary ammonium cationic comonomer
Authors: Wu Y. M. , Chen Q. F. , Xu J. , Bi J. M. 
Published: December 2007

AbstractUsing aqueous solution of ammonium sulfate as medium, acrylamide (AM) and dimethylaminoethyl methacrylate methyl chloride (DMC) as main raw materials, poly(dimethylaminoethyl methacrylate methyl chloride) (PDMC) as stabilizer and 2,2′‐azobis (2‐amidinopropane) dihydrochloride (V‐50) as initiator, the cationic polyelectrolyte of P(DMC‐AM) was synthesized by aqueous dispersion polymerization. The effects of the major reaction variables on synthesis conditions, product characteristics (particle size and molecular weight), and polymerization rate were investigated. The polymerization was retarded by the presence of the ammonium sulfate. The optimum reaction conditions for obtaining a stable aqueous dispersion were concentrations of 1.8 × 10−4–7.0 × 10−4mol L−1for V‐50, 1.5–3.5% for stabilizer, and 23.2–30.0% for salt. The molecular weight of PDMC formed was 1.5 × 105to 7.0 × 105. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation of porous PVdF membrane via thermally induced phase separation using sulfolane
Authors: Cui Zhen‐Yu , Du Chun‐Hui , Xu You‐Yi , Ji Gen‐Liang , Zhu Bao‐Ku 
Published: December 2007

AbstractSulfolane was acted as a kind of diluent to prepared PVdF porous membranes via TIPS process. Its impact on structure and morphology was studied. Phase diagram for this system was determined by different scanning calorimetry (DSC). Not any structure in the region higher than the dynamic crystallization temperature can be found and the temperature at which particle formation was observed by the optical microscope was approximately in agreement with the dynamic crystallization temperature, which revealed that only S–L phase separation happened for PVdF/sulfolane system during TIPS process. It was found that the heat of crystallization increased with the increase of polymer content. The increase of the cooling rate will increase the crystallization rate. SEM, which showed that membranes had symmetrical structure and pores formed between PVdF crystallization, revealed that PVdF will present different crystallization morphology as the cooling rate changed. With the cooling rate decrease, both the size of particles and the channel size of open pores between particles became larger, but more uneven. As the cooling rate increased, the size of particles decreased and pore became well interconnected and uniform, which were confirmed by the measurement of average pore size and pore size distribution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Unsymmetrical α‐diimine nickel (II) complex with rigid bicyclic ring ligand: Synthesis, characterization, and ethylene polymerization in the presence of AlEt2Cl
Authors: Li Ting , Zhang Chuan Hui , Zhu Fang Ming , Wu Qing 
Published: December 2007

AbstractUnsymmetrical α‐diimine ligand 1 was successfully synthesized via condensation of trimethylaluminum (TMA) metalated 2‐methyl‐6‐isopropyl‐aniline with rigid bicyclic aliphatic diketone camphorquinone. Syn‐ and anti‐stereoisomers were detected by 13C NMR in the condensation product. The corresponding α‐diimine nickel (II) complex 1 was prepared from the exchange reaction of (DME)NiBr2 with the ligand 1, and displayed high activity for ethylene polymerization in the presence of diethylaluminum chloride (AlEt2Cl). The resultant polymers were confirmed by gel permeation chromatography and 13C NMR characterization to be broad molecular weight distribution polyethylene with various branches, and high degree of branching, even at low polymerization temperature −10°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of novel moisture‐curable polyurethanes end‐capped with alkoxysilane and use as solvent‐free elastic adhesives
Authors: Nomura Yukihiro , Sato Akihiro , Sato Shinichi , Mori Hideharu , Endo Takeshi 
Published: December 2007

AbstractNovel silane endcappers and novel polyurethanes end‐capped with alkoxysilane (silylated polyurethanes) were developed as moisture‐curable materials, in which curing reaction occurs under humid conditions in the presence of dioctyltin diversatate as a curing catalyst. Two secondary amine‐terminated alkoxysilane compounds (silane endcappers) were synthesized by Michael addition reaction of commercially available N‐(2‐aminoethyl)‐3‐aminopropyltrimethoxysilane (or N‐(2‐aminoethyl)‐3‐aminopropylmthyldimethoxysilane) with methyl acrylate. The resulting silane endcappers were utilized to end‐capped isocyanate‐terminated polyurethanes, providing the silylated polyurethanes. The physical properties of the moisture‐curable silylated polyurethanes derived from several polyols and the silane endcappers were evaluated in terms of 50% modulus, tensile strength at break, elongation at break, and Shore A hardness after curing. The longer main chain of the silylated polyurethanes led to the lower Shore A hardness, the lower 50% modulus, and the longer elongation at break. In contrast, the tensile strengths at break were almost the same for all silylated polyurethanes, irrespective of the length of the main chain and the structure of the terminal silyl group. The silylated polyurethanes were employed for the preparation of novel solvent‐free moisture‐curable elastic adhesives, which were evaluated at the tensile shear bond strength. No significant influence of the molecular weight of the polyols and silane endcappers was observed on the tensile shear bond strength. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thermally stable polyurethane‐ureas and copolyurethane‐ureas containing zinc and nickel dihydroxysaltrien complexes
Authors: Khamma Nittaya , Krisiri Datchanee , Tachaprasertporn Prakaywan , Chantarasiri Nuanphun 
Published: December 2007

AbstractNew 4,4′‐dihydroxysaltrien metal complexes, (MOHSal2trien, where M = Zn and Ni) were synthesized and used for the synthesis of metal‐containing polyurethane‐ureas and copolyurethane‐ureas. MOHSal2trien underwent polymerization reaction with two diisocyanates, namely 4,4′‐diphenylmethane diisocyanate (MDI) and isophorone diisocyanate (IPDI) to yield polyurethane‐ureas. Copolyurethane‐ureas were synthesized by the reaction between MOHSal2trien, MDI, and diamines or dialcohols. The diamines or dialcohols employed were 4,4′‐methylenedianiline (MDA), hexamethylenediamine (HMA), bisphenol A (BPO), and hexamethylene glycol (HMO). The polymers were characterized by IR, NMR, elemental analysis, XRD, solubility, and viscosity. Thermal stability and flammability of polymers were studied by thermogravimetric analysis (TGA) in air and by measuring limiting oxygen index (LOI) values, respectively. It was found that the resulting metal‐containing polyurethane‐ureas and copolyurethane‐ureas exhibited good thermal stability. Among all metal‐containing polyurethane‐ureas, NiOHSal2trien‐MDI was the most thermally stable polymer with char yield of 55% at 600°C. Solubility in DMSO of zinc‐containing copolyurethane‐ureas based on dialcohols was greatly improved when compared with those of zinc‐ and nickel‐containing polyurethane‐ureas. ZnOHSal2trien‐MDI‐BPO and ZnOHSal2trien‐MDI‐HMO gave high char yield of 46% at 600°C, which is almost comparable with that of NiOHSal2trien‐MDI. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effects and optimization of processing parameters in water‐assisted injection molding
Authors: Huang Han‐Xiong , Deng Zhi‐Wu 
Published: December 2007

AbstractExperiments of water‐assisted injection molded polypropylene curved pipe were carried out on newly developed equipment in this lab. First, four processing parameters, including short‐shot size, melt temperature, water injection delay time, and water pressure, were investigated in terms of their effects on the water penetration length and residual wall thickness of curved pipe. Second, an orthogonal array of Taguchi, the S/N ratio, and ANOVA were utilized to find the optimal processing parameters resulting in maximum water penetration length. Finally, the crystallization behavior difference between the beginning and the end of the water channel of the curved pipe was analyzed using differential scanning calorimetry. It was interesting to find that the crystallinity of sample from the middle is higher than those from both outer and inner layers at position near the water inlet. The samples taken from the outer layer, middle, and inner layer show similar melting peak and crystallinity at position near the end of water channel. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Fluid biomulching based on poly(vinyl alcohol) and fillers from renewable resources
Authors: Chiellini E. , Cinelli P. , Magni S. , Miele S. , Palla C. 
Published: December 2007

AbstractThis article reports on the results obtained in an investigation on the application of biodegradable polymeric materials in the agricultural practice of mulching. Particular attention has been devoted to the effect of biobased mulching films generated in situ by low‐pressure spraying of polymeric water dispersions on the various cultivars. In a field trial, the effectiveness of the hydromulching (liquid‐mulching) technique was assessed by the monitoring of the growth and yield of lettuce and corn, which were used as reference plants. Conventional plastic films and straw mulching (SM) were compared with liquid‐mulching treatments based on poly(vinyl alcohol) and natural fillers derived from agroindustrial wastes (sugar cane bagasse, wheat flour, saw dust, and wheat straw). An improvement of the biomass yield of the two selected plants with respect to conventional polyethylene mulching was attained in various liquid‐mulching formulations with positive effects on the maintenance of soil structure. Alternative fluid‐mulching treatments based on biodegradable components were effective in preserving soil aggregates and improving some crop growth parameters. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Use of input selection techniques to improve the performance of an artificial neural network during the prediction of yarn quality properties
Authors: Mwasiagi Josphat Igadwa , Wang Xin Hou , Huang Xiu Bao 
Published: December 2007

AbstractThe performance of an artificial neural network (ANN) is affected by the number and types of inputs. The aim of this article is to study the performance of ANN algorithms, used for the prediction of cotton yarn strength, elongation, and evenness, as the input units are subtracted (skeletonized) and added to the input layer. Nineteen factors, consisting of fiber properties, processing parameters, and yarn quality properties, were used as the main source of inputs. The initial sets of inputs, which were selected on the basis of their relationship with the output factors, were 13, 13, and 12 for yarn strength, elongation, and evenness, respectively. The final sets of inputs were 14 factors for the three yarn quality properties being predicted, and the new ANN algorithms showed performance improvement of 40, 37, and 47% for strength, elongation, and evenness, respectively, when compared to the algorithms with 19 factors. Yarn twist, fiber length, and fiber length uniformity were common among the five most influential factors affecting yarn strength, elongation, and evenness, accounting for 40, 37, and 37% for the prediction of yarn strength, elongation, and evenness, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
In situ fibrous structure oriented polymer blends composed of poly(lactic acid) and polycaprolactone containing peroxide
Authors: Semba Takeshi , Kitagawa Kazuo , Kotaki Masaya , Hamada Hiroyuki 
Published: December 2007

AbstractA fibrous dispersed phase stuffed with polycaprolactone (PCL) was constructed in a poly(lactic acid) (PLA) matrix during an injection‐molding process. The injection‐molding process showed efficiency in forming dispersions with fibrous shapes, and they could impart the ductile property of PCL to the brittle PLA matrix, with appropriate interfacial adhesion arising from the cocrosslinking structure at the PLA/PCL interface by dicumyl peroxide (DCP). However, the addition of excess DCP caused a split of the dispersions resulting from the compatibility increment and the excess crosslinking reaction at the interface and inside each phase. The addition of a small amount of DCP could adhere the interface without splitting of the dispersions. The observed internal structure in the injection moldings showed a morphology transition that changed gradually from a fine fibrous morphology to a coarse morphology at a deeper position in the injection moldings. The tensile properties of sliced local layers, which were fabricated with a sliding microtome, proved that the fibrous morphology was effective in the improvement of ductility of the blends. An X‐ray analysis showed that the shear flow increased the crystalline orientation and formed a different crystalline structure only in the PCL dispersed phase, but its crystalline structure was not the main factor for ductility improvement. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Viscosity behavior of microwave‐heated and conventionally heated poly(ether sulfone)/dimethylformamide/lithium bromide polymer solutions
Authors: Idris Ani , Ahmed Iqbal 
Published: December 2007

AbstractThis article investigates the viscosity behavior of new membrane dope solutions of poly(ether sulfone) (PES) and dimethylformamide with low‐molecular‐weight halogenated lithium bromide (LiBr) additives prepared with two different techniques: (1) a microwave (MW) technique and (2) a conventional heating (CH) technique. In addition, the influence of different concentrations of anhydrous halogenated LiBr additives (0–5 wt %) on the viscosity behavior is analyzed. The viscosity of the dope solutions was assessed with a conical rheometer equipped with a high‐viscosity adapter. The results revealed that the pure PES solutions prepared by the MW and CH techniques exhibited pseudoplastic and Newtonian behavior, respectively. Both the MW and CH PES solutions containing the LiBr additives exhibited dilatant behavior, which obeyed the power law. The apparent viscosity of all the dope solutions prepared with the MW technique was lower than that of those prepared with the CH technique. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effect of UV‐photocrosslinking on the nonisothermal crystallization kinetics of polyethylene
Authors: Tang Longxiang , Yan Manqing , Liu Chunhua , Wang Pinghua , Qu Baojun 
Published: December 2007

AbstractThe influences of UV‐photocrosslinking on crystallite structure and nonisothermal crystallization kinetics of polyethylene (PE) were investigated by optical microscope (OM) and differential scanning calorimetry (DSC) at different cooling rates, respectively. The observation of crystallite structure showed that, due to crosslinking of molecular chains of PE, the PE spherulites grow more imperfectly with increasing gel content. The Avrami analysis modified by Jeziorny was applied to describe the nonisothermal crystallization process of virgin PE and photocrosslinked PE (XLPE) samples. The values of half‐time of crystallization t1/2 and the parameter Zc showed that the crystallization rate increased with increasing cooling rates for both XLPE and virgin PE, but the crystallization rate of XLPE is lower than that of virgin PE at the same cooling rate. The activation energies were estimated by the Kissinger method, and the values were 176.7 and 197.1 kJ/mol for virgin PE and XLPE, respectively, indicating that UV‐photocrosslinking might hinder the overall nonisothermal crystallization process of PE. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Grafting polymer from poly(ethylene terephthalate) films by surface‐initiated ATRP
Authors: Zhang Hongwen , Shouro Daisuke , Itoh Koichi , Takata Tadahiko , Jiang Yan 
Published: December 2007

AbstractSurface‐initiated atom transfer radical polymerization (ATRP) from poly(ethylene terephthalate) (PET) film was studied. Poly(methyl methacrylate) (PMMA), poly (acrylamide) (PAAM), and their diblock copolymer (PMMA/PAAM) on the surface of PET film were successfully prepared by surface‐initiated ATRP. The structures and properties of the modified PET film were characterized by FT‐IR/ATR, X‐ray photoelectron spectroscopy (XPS), measurements of contact angles, and scanning electronic microscopy (SEM). The results indicate that the surface properties of PET film were greatly improved by grafted polymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Oxidative radical generation via nitrogen dioxide dimer conversions induced by amide groups of macromolecules
Authors: Davydov E. Ya. , Gaponova I. S. , Pokholok T. V. , Pariiskii G. B. , Zaikov G. E. 
Published: December 2007

AbstractThe features of initiation of free radical reactions in polymers by dimers of nitrogen dioxide are considered. The conversion of planar dimers into nitrosyl nitrate in the presence of amide groups of macromolecules has been revealed. Nitrosyl nitrate initiates radical reactions in oxidative primary process of electron transfer with formation of intermediate radical cations and nitric oxide. As a result of subsequent reactions, nitrogen‐containing radicals are produced. The dimer conversion has been exhibited by estimation of the oxyaminoxyl radical yield in characteristic reaction of p‐benzoquinone with nitrogen dioxide on addition of aromatic polyamide and polyvinylpyrrolidone to reacting system. The isomerization of planar dimers is efficient in their complexes with amide groups, as confirmed by ab initio calculations. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation, morphology, and physical properties of transparent PSt hybrid materials containing silicone macromonomer
Authors: Daimatsu Kazuki , Anno Yusuke , Sugimoto Hideki , Nakanishi Eiji , Inomata Katsuhiro , Ikeda Tomoki , Yokoi Kazuki 
Published: December 2007

AbstractThe aim of this study was to prepare transparent polystyrene (PSt) hybrid materials containing silicone macromonomer. Silicone urethane methacrylate (SiUMA) was synthesized by the reaction between the hydroxyl end groups of a silicone macromonomer and the isocyanate group of 2‐methacryloyloxyethyl isocyanate (MOI), and copolymers with different weight proportions were prepared by copolymerization of styrene (St), SiUMA and ethyleneglycol dimethacrylate (EGDMA). Though the prepared P(St‐co‐SiUMA) copolymers which had not introduced EGDMA were opaque, the prepared P(St‐co‐SiUMA‐co‐EGDMA) copolymers were transparent, similarly to pure PSt. DSC and 1H‐NMR measurements were carried out to investigate the factors in this transparency in detail. From these measurement results, it was confirmed that the reactivity of the copolymerization had a significant influence on the transparency of the product. In addition, the contact angle of P(St‐co‐SiUMA‐co‐EGDMA) with 10 wt % SiUMA was greater than 90°, which was a 10° improvement compared to pure PSt. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Alkaline dyeing of polyester and polyester/cotton blend fabrics using sodium edetate
Authors: Youssef Y. A. , Ahmed Nahed S. E. , Mousa A. A. , El‐Shishtawy Reda M. 
Published: December 2007

AbstractAn alkaline dyeing of polyester with an alkali‐stable disperse dye, Dianix® Scarlet AD‐RG, was developed using sodium edetate as an alkaline buffering agent. The results obtained indicate the suitability of using sodium edetate for alkaline dyeing of polyester when compared with the control alkaline dyeing using Dianix AD system. Selected mono and bifunctional reactive dyes were used in combination with the alkali‐stable disperse dye for dyeing of polyester/cotton blend. Different dyeing methods for cotton and polyester/cotton blend fabrics using sodium edetate were evaluated in comparison with their respective control alkaline dyeing methods. The results of using sodium edetate in one‐bath two‐stage and two‐bath dyeing of polyester/cotton blend were comparable with that of the control dyeing method. Particularly, no change in the leveling and fastness properties was evaluated for all samples irrespective of the dyeing method. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008