bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of silicon dioxide/polyurethane nanocomposites by a sol–gel process
Authors: Zhu Yan , Sun Duo‐Xian 
Published: March 2004

AbstractAqueous emulsions of cationic polyurethane ionomers, based on poly(ϵ‐caprolactone glycol) as soft segment, isophorone diisocyanate as hard segment, 3‐dimethylamino‐1,2‐propanediol as chain extender and potential ionic center, and hydrochloric acid as neutralizer, were mixed with tetraethoxysilane to prepare silicon dioxide–polyurethane (SiO2/PU) nanocomposites by a sol–gel process during which the inorganic mineral is deposited in situ in the organic polymer matrix. The sizes and distributions of the particles were measured by dynamic light scattering, and the structure and morphology of the nanocomposites were observed by transmission electron microscope and FTIR spectrum. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2013–2016, 2004
Study on the mechanical properties of hybrid reinforced rigid polyurethane composite foam
Authors: Yang Zhen‐Guo , Zhao Bin , Qin Sang‐Lu , Hu Zheng‐Fei , Jin Zhong‐Kao , Wang Jian‐Hua 
Published: March 2004

AbstractThe mechanical properties of hybrid reinforced rigid polyurethane (PU) foams were investigated with the reinforcing agent SiO2 and fibers. The effect of content of SiO2 and fibers and the effect of length of fibers on the properties of the PU composite foam were emphatically analyzed. The experiment results show that the tensile strength of the PU composite foam is optimal when the content of SiO2 and glass fiber is 20 and 7.8%, respectively. Furthermore, the reinforcing effect of glass fiber, Nylon‐66 fiber, and PAN‐matrix carbon fiber were compared and the results show that the tensile strength of the PU composite foam reinforced with 3–5% carbon fiber is optimal. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1493–1500, 2004
Synthesis of functionalized phenolformaldehyde polymer resins by the reaction of 2,4‐dihydroxyacetophenone formaldehyde resin with various amines and their metal ion uptake properties
Authors: Reddy A. Ravikumar , Reddy K. Hussain 
Published: March 2004

AbstractA series of functionalized phenolformaldehyde polymer resins have been synthesized by the reaction of 2,4‐dihydroxyacetophenone‐formaldehyde resin with the amines, such as ethanolamine, aminophenol, ethylenediamine, and propylenediamine in dichloromethane. The Schiffbase polymers were characterized by IR and 1H‐NMR spectroscopic techniques. Thermal stabilities of the polymers were determined by TG and DTA studies. Heavy and toxic metal ions viz., Pb(II), Hg(II), Cd(II), and Cr(VI) have been removed using these polymer resins. Metal uptake efficiency, reusability, effect of pH, effect of time, and effect of initial concentration on the metal uptake were also studied. Amount of metal removed by the resin was determined using atomic absorption spectrophotometry. The retention properties were also tested under competitive conditions and were found to be depend strongly on the pH. Elution of metal ions were investigated in acid media. The uptake behaviour of the resins was approximately described by Freundlich's equation. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1501–1509, 2004
Sorbents for removal surfactants from aqueous solutions: Surface modification of natural solids to enhance sorption ability
Authors: Łukaszczyk Jan , Łękawska Ewa , Lunkwitz Klaus , Petzold Gudrun 
Published: March 2004

AbstractParticulate materials of natural origin, sulfite cellulose and two kaolinite clays, were modified by the formation of nonstoichiometric polyelectrolyte complex on the surface of particles. This resulted in positive surface charge on cellulose and clays. Modified materials as well as selected commercial polymers were used as sorbents for removal of anionic, nonionic, and cationic surfactants from aqueous solutions. It was stated that cationic surface modification of cellulose and kaolinite clays resulted in a significant increase of sorption rate and degree of removal of oppositely charged anionic surfactants. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1510–1515, 2004
Synthesis of new soluble aromatic poly(amide imide)s from unsymmetrical extended diamine containing phthalazinone moiety
Authors: Cheng Lin , Jian Xi Gao 
Published: March 2004

AbstractThe preparation of a new unsymmetrical kink non‐coplanar heterocyclic diamine, 1,2‐dihydro‐2‐(4‐aminophenyl)‐4‐[4‐(3‐phenyl‐4‐aminophenoxy)phenyl]‐(2H)phthalazin‐1‐one (3), from a readily available unsymmetrical phthalazinone bisphenol‐like (1) was described. The diamine can be directly polymerized with various aromatic bis(trimellitimide)s (4a–e) by using triphenyl phosphite and pyridine as condensing agents to give a series of new aromatic poly(amide imides) (5a–e) containing the kink non‐coplanar phthalazinone heterocyclic units with inherent viscosities of 0.57–1.06 dL/g. The polymers were readily soluble in a variety of solvents such as N,N‐dimethylformamide, N,N‐dimethylacetamide, dimethylsulfoxide, N‐methyl‐2‐pyrrolidinone, and even in pyridine and m‐cresol and could be cast to form flexible and tough films. The glass transition temperatures were in the range of 315–340°C, and the temperatures for 5% weight loss in nitrogen were in the range of 487–512°C. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1516–1520, 2004
Processing thermal stability and degradation kinetics of poly(vinyl chloride)/montmorillonite composites
Authors: Wan Chaoying , Tian Guohua , Cui Ning , Zhang Yinxi , Zhang Yong 
Published: March 2004

AbstractThermal stability of polyvinyl chloride (PVC) based montmorillonite composites with either sodium montmorillonite (MMT) or alkyl ammonium ion modified montmorillonite (OMMT) were investigated by thermogravimetric analysis. The apparent activation energies associated with the first thermal degradation stage were calculated by the methods of Flynn–Wall–Ozawa and Kissinger in nitrogen atmosphere at several different heating rates. The processing thermal stability of PVC and PVC/MMT(OMMT) composites was also discussed. Increase of mixing torque did not result in a larger intercalation extent of PVC on MMT; instead, it unexpectedly induced discoloration of PVC and then deteriorated the processing stability, especially in the presence of OMMT. The apparent activation energies in the first thermal degradation stage exhibited little difference among PVC, PVC/MMT, and PVC/OMMT composites, and the kinetic compensation effect of Sp* kept a constant value, indicating that the thermal stability and thermal degradation mechanism of PVC were not affected by the presence of either MMT or OMMT, although the processing discoloration of PVC is observed for PVC/OMMT composite. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1521–1526, 2004
Studies on γ‐Fe2O3–high‐density polyethylene composites and their additives
Authors: Govindaraj B. , Sastry N. V. , Venkataraman A. 
Published: March 2004

Abstractγ‐Fe2O3–high‐density polyethylene (HDPE) composite films are prepared by a gel‐casting technique. To understand the effect of additives, rice husk ash and thiourea are made to disperse in the HDPE matrix to obtain the composite films with additives. The as‐prepared γ‐Fe2O3–HDPE composite films with their additives are subjected to characterization and study through X‐ray diffraction, thermal, scanning electron microscopy, and dielectric measurements. The results are qualitatively treated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1527–1533, 2004
Isotactic polypropylene microfiber prepared by carbon dioxide laser‐heating
Authors: Suzuki Akihiro , Narusue Shinichi 
Published: March 2004

AbstractAn isotactic polypropylene (i‐PP) microfiber was obtained by irradiating a carbon dioxide laser to previously drawn fibers. To prepare the thinner i‐PP microfiber, it is necessary to previously draw original i‐PP fibers under an applied tension of 7.8 MPa at a drawing temperature of 140°C. The drawn fiber was heated under an applied tension of 0.3 MPa using the laser operated at a power density of 39.6 W cm−2. The thinnest i‐PP microfiber obtained under optimum conditions had a diameter of 1.8 μm and a birefringence of 30 × 10−3. Its draw ratio estimated from the diameter reached 51,630. It is so far impossible to achieve such a high draw ratio by any drawing. The wide‐angle X‐ray diffraction photograph of the microfiber shows the existence of the oriented crystallites. Laser‐heating allows easier fabrication of microfibers compared with the conventional technology such as the conjugate spinning. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1534–1539, 2004
Synthesis and characterization of spinning poly(acrylonitrile‐co‐silk fibroin peptide)s
Authors: Chen Zhongmin , Suzuki Masahiro , Kimura Mutsumi , Kondo Yoshiyuki , Hanabusa Kenji , Shirai Hirofusa 
Published: March 2004

AbstractA novel spinning acrylic polymer containing silk protein was synthesized by copolymerization of acrylonitrile (AN) and silk fibroin peptide (SFP) modified by acryloyl chloride (AC) with vinyl groups. From results of the examination to the chemical compositions, we established that the modified SFP is more reactive than AN in the copolymerization. The intrinsic viscosity values of these copolymers showed that the copolymers have good spinnability, which were synthesized under the condition of adding a trace of metal ions into the synthesizing solvent. These copolymers exhibited good thermal property. The fiber based on the poly(acrylonitrile‐co‐silk fibroin peptide) was prepared and characterized by SEM, FTIR measurement of its shell and core flakes, and moisture absorption. The fiber exhibited a smooth surface and could be assumed to have excellent adhesive property between SFP and PAN. Furthermore, these fibers showed a core–shell structure and excellent moisture absorption. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1540–1547, 2004
Rod‐climbing characteristics of α‐Fe2O3 suspended polyisobutylene/polybutene solution
Authors: Lim Sung T. , Choi Hyoung J. , Jhon Myung S. 
Published: March 2004

AbstractFrom rod‐climbing rheometer measurements, we systematically investigated the normal stress values of suspended particles in polymeric liquids at low shear rates using the second‐order fluid constitutional relationship. The climbing constants β of the suspended α‐Fe2O3 particles in polyisobutylene/polybutene solutions, which exhibit Boger fluid characteristics (highly elastic, but no shear‐thinning), were estimated from the rod‐climbing experiment, showing that β increased with polymer concentration and polymer molecular weight. The first normal stress difference coefficient of the suspended α‐Fe2O3 in polymeric liquids obtained from the rod‐climbing rheometer was well correlated with the rheological properties measured by rotational rheometers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1548–1552, 2004
Novel model for uniaxial strain‐rate–dependent stress–strain behavior of ethylene–propylene–diene monomer rubber in compression or tension
Authors: Song Bo , Chen Weinong , Cheng Ming 
Published: March 2004

AbstractBased on quasi‐static and dynamic experimental results, a novel strain‐rate–dependent model for ethylene–propylene–diene monomer (EPDM) rubber was developed. This model, composed of a base model and rate‐sensitivity terms, has a relatively simple form to be embedded in computer codes for numerical simulations. The base model combines a Maxwell model and a Mooney function. The Maxwell model is necessary to describe small‐strain behavior, whereas the Mooney function dominates the large‐strain behavior. Each of these two components is then multiplied by a rate‐sensitive term to describe the material's strain‐rate sensitivities at both small and large strains. This model gives a good description of EPDM response in both compression and tension over a wide range of strain rates with a minimum number of material constants. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1553–1558, 2004
Partially miscible blends based on a polyarylate and poly(trimethylene terephthalate)
Authors: Guerrica‐Echevarria G. , Eguiazábal J. I. , Nazábal J. 
Published: March 2004

AbstractThe miscibility of blends of a polyarylate (PAr) with poly(trimethylene terephthalate) (PTT) was investigated in the whole composition range by DSC measurements. With the exception of the 90/10 composition, which was fully miscible, the blends showed partial miscibility, and contained a nearly pure PTT phase and a PAr‐rich phase with 18% PTT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1559–1561, 2004
Study of the miscibility and crystallization behavior of poly(ethylene oxide)/poly(vinyl alcohol) blends
Authors: Lai Wei‐Chi , Liau Wen‐Bin 
Published: March 2004

AbstractThe miscibility and crystallization behavior of poly(ethylene oxide)/poly(vinyl alcohol) (PEO/PVA) blends were investigated by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and polarizing optical microscopy. Because the glass‐transition temperature of PVA was near the melting point of PEO crystalline, an uncommon DSC procedure was used to determine the glass‐transition temperature of the PVA‐rich phase. From the DSC and DMA results, two glass‐transition temperatures, which corresponded to the PEO‐rich phase and the PVA‐rich phase, were observed. It was an important criterion to indicate that a blend was immiscible. It was also found that the preparation method of samples influenced the morphology and crystallization behaviors of PEO/PVA blends. The domain size of the disperse phase (PVA‐rich) for the solution‐cast blends was much larger than that for the coprecipitated blends. The crystallinity, spherulitic morphology, and isothermal crystallization behavior of PEO in the solution‐cast blends were similar to those of the neat PEO. On the contrary, these properties in the coprecipitated blends were different from those of the neat PEO. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1562–1568, 2004
Grafting of polyacrylonitrile onto guar gum under microwave irradiation
Authors: Singh Vandana , Tiwari Ashutosh , Tripathi Devendra Narayan , Sanghi Rashmi 
Published: March 2004

AbstractUsing microwave (MW) irradiation grafting of polyacrylonitrile (PAN) onto guar gum in water was done without using any radical initiator or catalyst within a very short reaction time. The extent of grafting could be adjusted by controlling the reaction conditions and maximum percentage grafting (%G) of about 188% was obtained under optimum conditions in 1.66 min. The average molecular weight of the grafted PAN chains and water‐retention power of the alkali hydrolyzed MW‐grafted gums were also determined and compared with those of the conventionally synthesized (cs) graft copolymer. A representative MW‐grafted copolymer, guar‐g‐polyacrylonitrile was characterized by IR, NMR, XRD, TGA, and elemental analysis. A plausible mechanism for the grafting under MW was proposed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1569–1575, 2004
Selection of a precursor of a monofunctional polyhedral oligomeric silsesquioxane reacted with aromatic diamines
Authors: Ramírez C. , Vilariño J. M. L. , Abad M. J. , Barral L. , Bouza R. , Cano J. , Díez F. J. , García‐Garabal S. , López J. 
Published: March 2004

AbstractWith the aim of selecting a precursor of a polyhedral oligomeric silsesquioxane (POSS) reacted with aromatic diamines for its incorporation into an epoxy network, to generate an organic–inorganic hybrid material containing POSS, a polyhedral oligomeric silsesquioxane (glycidylisobutyl–POSS) was reacted with the diamines 4,4′‐methylenebis(2,6‐diethylaniline) (MDEA), 4,4′‐diaminediphenylmethane (DDM), and 4,4′‐(1,3‐phenylenediisopropylidene)bisaniline (BSA), at 160°C and different times, in a proportion rich in amines. The distribution of species in the reaction was followed by gel permeation chromatography (GPC). From the experimental data obtained the selected precursor was POSS/BSA reacted at 160°C for 20 or 30 min, to ensure that all the POSS was reacted, that there was a maximum of the monosubstituted amines, and that there was no degradation. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1576–1583, 2004
Studies of adsorption properties of crosslinked chitosan for vanadium(V), tungsten(VI)
Authors: Qian Shahua , Wang Haoyun , Huang Ganquan , Mo Shaobo , Wei Wu 
Published: March 2004

AbstractIn this article, the adsorption properties of crosslinked chitosan (CCTS) for V(V) and W(VI) were studied. Experimental results showed the adsorption rates of CCTS for V(V) and W(VI) were closely related to the acidity of solution. The adsorption rates were 97% for V(V) at pH 4.0 and 96% for W(VI) at pH 4.5. The adsorption balance times, adsorption capacities, and adsorption mechanism were explored. This research is of significance for removal of V(V) and W(VI) in industrial wastewater and their preconcentration in trace analysis. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1584–1588, 2004
Surface grafting of polyacrylamide from polyethylene‐based copolymer film
Authors: Luo Ning , Husson Scott M. , Hirt Douglas E. , Schwark Dwight W. 
Published: March 2004

AbstractAtom transfer radical polymerization (ATRP) was used to grow polyacrylamide from the surface of ethylene–acrylic acid copolymer (EAA) film. The surface functionalization constituted initiator immobilization and surface graft polymerization. All reaction steps were conducted at 24 ± 3°C; polymerization was done in aqueous solution. For initiator immobilization, the carboxylic acid groups on EAA film were converted to acid chloride groups; further reaction with ethanolamines gave hydroxyl groups onto which 2‐bromoisobutyryl bromide initiator was attached. ATR‐FTIR data indicated that 1.64 ± 0.09 times higher initiator density was achieved by using diethanolamine, relative to ethanolamine. Acrylamide monomer was polymerized from the initiator by ATRP to yield nondistorted, transparent films with polymerization times of up to 1 h. For films prepared using diethanolamine, 1 h polymerization time reduced the static water contact angle by more than 50°, significantly increasing the hydrophilicity of the film surface. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1589–1595, 2004
Studies on poly(acrylic acid)/attapulgite superabsorbent composite. I. Synthesis and characterization
Authors: Li An , Wang Aiqin , Chen Jianmin 
Published: March 2004

AbstractA novel poly(acrylic acid)/attapulgite superabsorbent composite was synthesized by graft copolymerization reaction of acrylic acid (AA) on attapulgite micropowder using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and ammonium persulfate (APS) as an initiator in aqueous solution. The effects on water absorbency of such factors as reaction temperature, initial monomer concentration, degree of neutralization of AA, amount of crosslinker, initiator, and attapulgite were investigated. These crosslinked superabsorbent composites were characterized by thermogravimetetric analysis and scanning electron microscopy. The graft copolymerization reaction of AA on attapulgite micropowder was characterized by FTIR. The water absorbencies for these superabsorbent composites in water and saline solutions were investigated and water‐retention tests were carried out. Results obtained from this study show that the water absorbency of the superabsorbent composite synthesized under optimal synthesis conditions with an attapulgite content of 10% exhibited an absorption of 1017 g H2O/g sample and 77 g H2O/g sample in distilled water and in 0.9 wt % NaCl solution, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1596–1603, 2004
Processing and chemorheology of epoxy resins and their blends with dendritic hyperbranched polymers
Authors: Ratna D. , Varley R. , Simon G. P. 
Published: March 2004

AbstractToughened epoxy systems have found increasing applications in automotive, aerospace, and electronic packaging industries. The present article reported work done for elucidation of gelation and vitrification for various epoxy systems and their blends with dendritic hyperbranched polymers (HBPs) having epoxy and hydroxyl functionality. Gel time was found to increase with increasing functionality from diglycidyl ether of bisphenol A (DGEBA) to tetraglycidyl diaminodiphenyl methane (TGDDM). The vitrification point was clearly identified from rheological experiments for triglycidyl p‐amino phenol (TGAP) and TGDDM. In the case of DGEBA a clear display of vitrification was not observed. TGDDM underwent vitrification sooner than did TGAP. Hydroxyl‐functionalized HBP reduced the gel time of the blends because of the accelerating effect of –OH groups to the epoxy curing reaction. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1604–1610, 2004
Preparation of positive‐temperature coefficient heaters using platinum‐catalyzed silicone rubber
Authors: Park Eun‐Soo , Yun Sung‐Jin , Kim Gwang‐Tae , Park Ill‐Joon , Choi Won‐Hyuck , Jeong Ji‐Woong , Hong Sung‐Young , Park Hyun‐Woo , Jang Lee Wook , Yoon Jin‐San 
Published: March 2004

AbstractVarious output heaters were extruded with acetylene black–filled platinum‐catalyzed silicone rubber. The resistivity–temperature behavior of extruded heaters exhibited a positive‐temperature coefficient (PTC) effect without any negative‐temperature coefficient (NTC) effect. Resistivity and thermal reproducibility of the extruded heaters were investigated during heating and cooling cycles at an applied voltage of 220 V. These heaters initially showed poor reproducibility of resistivity during the repeated cycles and this effect increased significantly as the acetylene black content decreased. PTC effect and electrical reproducibility were improved significantly during the thermal ageing process. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1611–1617, 2004
Synthesis of superabsorbent resin by ultraviolet photopolymerization
Authors: Ruan Weiqing , Qiao Jinliang , Huang Yuli , Niu Aijie 
Published: March 2004

AbstractSynthesis of superabsorbent resin (SAR) was achieved by a new method, that of direct UV photopolymerization, and in particular the synthesis of a SAR of acrylic acid–potassium acrylate copolymer by UV photopolymerization was investigated. Influences of ratio (mol) of acrylate monomer to acrylic acid monomer, photoinitiators, crosslinking agents, and exposure time of UV light on the water‐absorbent properties were investigated. The results showed that the water absorbency (Q) of SAR based on Irgacure 1700 or Irgacure 1800 was 545–530 mL/g, but under the same conditions Q was 450 mL/g for the SAR based on Irgacure 651. N,N′‐Methylene bisacrylamide, hydroethyl acrylate, and glycerol were used as crosslinking agents, of which N,N′‐methylene bisacrylamide was the most effective. It crosslinked the molecular chains through attending the copolymerization with acrylic acid (AA) and potassium acrylate. When the exposure time was 5 min, the value of Q was 1368 mL/g (the content of N,N′‐methylene bisacrylamide was 100 ppm). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1618–1624, 2004