bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactive grafting of glycidyl methacrylate onto polypropylene
Authors: Burton Emma‐Louise , Woodhead Mike , Coates Phil , Gough Tim 
Published: April 2010

AbstractThis work explored the melt‐phase grafting of glycidyl methacrylate (GMA) onto polypropylene on a closely intermeshing corotating twin‐screw extruder (16‐mm screws, 40 : 1 length/diameter ratio). The modification of the base polypropylene to produce GMA‐grafted polypropylene was achieved via peroxide‐induced hydrogen abstraction from the polypropylene followed by the grafting of the GMA monomer or by the grafting of styrene followed by copolymerization with the GMA. In this study, both the position and order of the reactant addition were investigated as a route to improving graft yields and reducing side reactions (degradation). For the peroxide–GMA system, adding GMA to the melt before the peroxide resulted in significant improvements in the graft levels because of the improved dispersion of GMA in the melt. The addition of a comonomer (styrene) was explored as a second route to improving the graft yield. Although the addition of the comonomer led to a considerable rise in the level of grafted GMA, altering the order of the reactant addition was not found to contribute to an increase in the grafted GMA levels. However, variable levels of grafted styrene were achieved, and this may play an important role in the development of grafted polymers to suit specific needs. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Compatibilizing effect of starch‐grafted‐poly(L‐lactide) on the poly(ε‐caprolactone)/starch composites
Authors: Chen Li , Zhang Zhe , Zhuang Xiuli , Chen Xuesi , Jing Xiabin 
Published: April 2010

AbstractThe poly(ε‐caprolactone) (PCL)/starch blends were prepared with a coextruder by using the starch grafted PLLA copolymer (St‐g‐PLLA) as compatibilizers. The thermal, mechanical, thermo‐mechanical, and morphological characterizations were performed to show the better performance of these blends compared with the virgin PCL/starch blend without the compatibilizer. Interfacial adhesion between PCL matrix and starch dispersion phases dominated by the compatibilizing effects of the St‐g‐PLLA copolymers was significantly improved. Mechanical and other physical properties were correlated with the compatibilizing effect of the St‐g‐PLLA copolymer. With the addition of starch acted as rigid filler, the Young's modulus of the PCL/starch blends with or without compatibilizer all increased, and the strength and elongation were decreased compared with pure PCL. Whereas when St‐g‐PLLA added into the blend, starch and PCL, the properties of the blends were improved markedly. The 50/50 composite of PCL/starch compatibilized by 10% St‐g‐PLLA gave a tensile strength of 16.6 MPa and Young's modulus of 996 MPa, respectively, vs. 8.0 MPa and 597 MPa, respectively, for the simple 50/50 blend of PCL/starch. At the same time, the storage modulus of compatibilized blends improved to 2940 MPa. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Macroporous poly(vinyl alcohol) foam crosslinked with epichlorohydrin for microorganism immobilization
Authors: Bai Xue , Ye Zhengfang , Li Yanfeng , Ma Yingxia 
Published: April 2010

AbstractMacroporous poly(vinyl alcohol) foam with epichlorohydrin as a crosslinking agent was investigated. The average molecular weight between crosslinks, crosslinking density, and mesh size were determined through the equilibrium swelling theory. The characterization of foams with different crosslinking ratios was also investigated through the testing of the thermal properties, specific surface areas, and diffusion coefficients. The biomass densities and activity yields were measured by detection of the protein concentration and oxygen uptake rate. Thermogravimetry and differential scanning calorimetry tests showed an increase in the thermal stability and a decrease in the polymeric crystallinity with increasing crosslinking ratio. The biomass densities increased with increasing crosslinking ratio, with the highest value shown at 0.0638 ± 0.0093 g of volatile suspended solid (VSS)/g of carrier. However, the activity yields decreased with increasing crosslinking ratio, with the highest value at 69.38%. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Micromechanical behavior related to the nanostructure of biodegradable polyesters
Authors: Cagiao M. E. , Buzin P. , Kricheldorf H. R. , Funari S. S. , Calleja F. J. Baltá 
Published: April 2010

AbstractThe microhardness of a series of biodegradable polyesters was determined. The nanostructural features of these materials were studied by wide‐angle X‐ray scattering (WAXS), small‐angle X‐ray scattering (SAXS), and differential scanning calorimetry. Analysis of the SAXS and WAXS patterns allowed direct derivation of the degree of crystallinity and crystal thickness values, and correlations of the micromechanical properties are presented. The differences in the thermal and mechanical properties exhibited by the studied systems and the ones found in other aromatic polyesters are explained as due to the different chemical natures of the monomeric units. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of aliphatic amine epoxy hardener on the adhesive properties of blends of mono‐carboxyl‐terminated poly(2‐ethylhexyl acrylate‐co‐methyl methacrylate) with epoxy resin
Authors: González Garcia Filiberto , Soares Bluma Guenther , Leyva Maria Elena , Simões Alexandre Zirpoli 
Published: April 2010

AbstractThe adhesive properties have been investigated in blends of mono‐carboxyl‐terminated poly(2‐ethylhexyl acrylate‐co‐methyl methacrylate) with diglycidyl ether of bisphenol A and three different aliphatic amine epoxy hardener. The adhesives properties are evaluated in steel alloy substrate using single‐lap shear test. The copolymers are initially miscible in the stoichiometric blends of epoxy resin and hardener at room temperature. Phase separation is noted in the course of the polymerization reaction. Different morphologies are obtained according to the amine epoxy hardener. The most effective adhesive for steel–steel joints in single‐lap shear test is the blends using 1‐(2‐aminoethyl)piperazine (AEP) as hardener. This system shows the biggest lap shear strength. However, the modified adhesives show a reduction in the mechanical resistance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of the preparation conditions on the permeation of ultrahigh‐molecular‐weight polyethylene/silicon dioxide hybrid membranes
Authors: Li Nana , Xiao Changfa 
Published: April 2010

AbstractPorous ultrahigh‐molecular‐weight polyethylene/SiO2 membranes were prepared by thermally induced phase separation (TIPS) with white mineral oil as the diluent and SiO2 as an additive. Influential factors, including extraction method, SiO2 content, and cooling rate, were investigated. The results suggest that the both porosity and pure water flux of the membranes by extraction of the solvent naphtha in the tension state with alcohol were the best among our research. With increasing SiO2 content, the porosity, pure water flux, and pore diameter increased. However, with excessive SiO2 content, defects formed easily. Moreover, SiO2 improved the pressure resistance of the membranes. The cooling rate directly effected the crystal structure. A slow cooling rate was good for crystal growth and the integration of the diluent. Therefore, the porosity, pure water flux, and bubble‐point pore diameter increased with decreasing cooling rate. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Surface modification of vulcanized rubber by radiation grafting, part 1: Improvement in friction behavior
Authors: Mizote N. , Katakai A. , Tamada M. , Matsuoka H. 
Published: April 2010

AbstractHydrophilic monomer, 2‐hydroxyethyl methacrylate (HEMA), and hydrophobic monomer, 3‐(methacryloyloxy)propyltris(trimethylsiloxy)silane (MPTS) were grafted on vulcanized rubber surface with simultaneous electron beam irradiation. Degree of graft polymerization was evaluated by composition ratio of imparted graft chain against trunk rubber. The composition ratio could be controlled by the monomer concentration and the irradiation dose. Grafted rubbers were evaluated by surface roughness and contact angle. Graft polymerization of HEMA decreased the contact angle from 93 to ∼ 70° without considerable change of the surface roughness. In the case of MPTS, the contact angle increased approximately to 108°. The relationship between the contact angle of water on the modified surface and the friction at the moment of semi‐dry was investigated as an application of the resulting rubber to wiper blade. The increase of the contact angle owing to the grafting of hydrophobic MPTS led to the decrease of Δμ (deference between semi‐dry state and dry friction). Instead, the decrease of the contact angle by grafting of hydrophilic HEMA resulted in the increase of Δμ. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Prepared hydrogenated nitrile rubber (HNBR)/organo–montmorillonite nanocomposites by the melt intercalation method
Authors: Zhang R. L. , Liu L. , Huang Y. D. , Tang Y. R. , Zhang T. C. , Zhan S. Z. 
Published: April 2010

AbstractThe polymer, Hydrogenated Nitrile‐Butadiene Rubber (HNBR) was melt compounded with organophilic montmorillonite (OMMT). The dispersion of the OMMT in the HNBR matrix was characterized by X‐ray diffraction (XRD), which indicated that at the temperature of 100°C, the organoclay belong to the exfoliated and interlayer structure. The effect of sulfur on the dispersion of OMMT in the polymer matrix was also studied. The vulcanization changed the dispersion of OMMT in polymer matrix greatly and the basal spacing of clay layers is decreased after vulcanization. The mechanical properties, Akron abrasion and the crude oil medium aging‐resistant of HNBR nanocomposites were examined as a function of the OMMT content in the matrix of polymer. The results of the test show remarkable improvement in tensile strength, tear strength, aging‐resistant, and hardness of HNBR nanocomposites than that of unfilled HNBR. It is obvious that the 10 phr of OMMT filled nanocomposites have the best mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Surfactant assisted processing of carbon nanotube/polypropylene composites: Impact of surfactants on the matrix polymer
Authors: Rausch Julius , Zhuang Rong‐Chuan , Mäder Edith 
Published: April 2010

AbstractMultiwalled carbon nanotubes (MWCNT) were dispersed in presence of various surfactants and introduced into isotactic polypropylene (PP) via melt blending. The effect of the surfactants on the crystallization and mechanical properties was studied on the injection molded specimens by isothermal differential scanning calorimetry and tensile tests, respectively. The results reveal that the presence of surfactants affects the mechanical and thermal properties of the nanocomposite. This information is supported by thermogravimetric analysis of the surfactants to examine their behavior at temperatures relevant for the processing of PP. In addition, they have to be taken into account as a third phase between the MWCNT and polymeric matrix, affecting the crystallization and failure behavior of PP or causing the formation of pores at elevated temperatures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Impact of curing condition on pH and alkalinity/acidity of structural wood adhesives
Authors: Zhang Yaolin , Wang Xiang‐Ming , Casilla Romulo , Cooper Paul , Huang Zeen , Wang Xiaodong 
Published: April 2010

AbstractNine formulations were selected for evaluating the effect of different curing methods on pH and alkalinity or acidity of various structural wood adhesives. These included four phenol–formaldehyde (PF) resins with high pH, one phenol–resorcinol–formaldehyde (PRF) resin with intermediate pH, two melamine–urea–formaldehyde (MUF) resins, and two melamine–formaldehyde (MF) resins with low pH. The four curing methods used in the study were: (1) curing at 102–105°C for 1 h (based on CSA O112.6‐1977), (2) four‐hour curing at 66°C followed by 1‐hour curing at 150°C (based on ASTM D1583‐01), (3) curing at room temperature overnight (based on ASTM D 1583‐01), and (4) cured adhesive squeezed out from glue lines of bonded shear block samples. The effect of the different methods on pH and alkalinity/acidity of the cured adhesive depended strongly on the individual adhesives. For the PF, the alkalinity was different for the different formulations in the liquid form, while in the cured form, the difference in the alkalinity depended on the curing method used. The MF and the MUF were the adhesives most affected by the method used. In particular, the MUF showed much higher cured film pH values when cured by method 2 compared to the other three methods, while both the cured MF and MUF exhibited quite variable acidity values when cured with the different methods. The PRF showed reasonably uniform cured film pH but varying acidity values when cured with the different methods. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Thermal properties of new bismaleimide resins containing hydrogen silsesquioxane and diallyl bisphenol A
Authors: Huang Fuwei , Huang Farong , Zhou Yan , Du Lei 
Published: April 2010

AbstractBismaleimide (BMI) resins modified with hydrogen silsesquioxane (HSQ) and diallyl bisphenol A (DABPA) (BMI‐HSQ‐DABPA resins) were prepared. DSC, FTIR, and TGA were used to characterize the curing behaviors, structures, and thermal properties of the BMI‐HSQ‐DABPA resins, respectively. The results showed that the glass transition temperatures and thermal stabilities of the cured BMI‐HSQ‐DABPA resins increased with the rise of the contents of HSQ. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A novel route for preparation of PVC sheets with high UV irradiation resistance
Authors: Ye Xianke , Pi Hong , Guo Shaoyun 
Published: April 2010

AbstractA novel acrylonitrile acrylate copolymer coating was proposed to improve the UV irradiation resistance of poly(vinyl chloride) (PVC) sheets. Its effect on the photoageing properties of the sheets was evaluated by means of Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), yellowness index test, and the oxygen permeability coefficient and mechanical properties measurement. The experimental results show that the novel acrylonitrile acrylate copolymer coating significantly improves the UV irradiation resistance of PVC sheets. Compared with the PVC sheets without coating, the coated PVC sheets show better mechanical properties, lower yellowness index, and smaller oxygen permeability coefficient after UV irradiation. The analysis on the SEM images of the PVC sheets indicates that the coating acts as a film to prevent the PVC sheets from UV energy and oxygen that can accelerate the photochemical reactions of PVC. The FTIR analysis confirms that the coating can slow down the microstructures development of the PVC sheets, also indicating that the coating impeded the photochemical reactions of PVC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Terpolymerization and performance of 2‐acrylamide‐2‐methyl propane sulfonic acid / itaconic acid / N‐vinyl‐2‐pyrrolidone
Authors: Zhang Liang , Zhuang Jia , Liu Hanbin , Li Huan Ming , Zhao Zhangping 
Published: April 2010

AbstractUsing 2‐acrylamide‐2‐methyl propane sulfonic acid (AMPS), itaconic acid (IA), and N‐vinyl‐2‐pyrrolidone (NVP) as monomers, a new retader terpolymer AMPS/IA/NVP (PAIN) was synthesized by free radical aqueous solution copolymerization and characterized by FTIR and H‐NMR. Through the orthogonal experiment, the optimum reaction conditions of copolymerization were obtained: NVP 7.5 wt (mass fraction) %; regulator V 4%; reaction temperature 60°C; initiator 1 wt %. The intrinsic viscosity number of PAIN synthesized with different amount of regulator (isopropanol) was determined, finding that the regulator can change the molecular weight and distribution of PAIN. Through the thickening experiment in high temperature and high pressure, it was found that PAIN had an excellent retardation property in high temperature, and the thickening times of the cement slurries with 1% (BOWC) PAIN were up to 256 min at 110°C and 234 min at 130°C, respectively. The PAIN was even stable when the temperature below 350°C proved by TG‐SDTA analysis. Moreover, the retarding mechanism of PAIN was analyzed and discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The role of temperature on the Egyptian drilling mud performance in the presence of cationic polyethylene imine and anionic polyacrylamide
Authors: Mostafa Bassem A. , Assaad Faiz F. , Rashad Mohamed A. , El‐Niklawy Ahmed S. 
Published: April 2010

AbstractThe flow properties of Egyptian bentonite suspensions were determined in the presence of cationic polyethylene imine followed by anionic polyacrylamide at different clay/water ratios. This sequence of addition was examined at four different temperatures (20, 40, 60, and 80°C). The aging time was kept constant after 24 h. The data showed that there is an inverse relation between temperature and plastic viscosity of the bentonite suspension. Contrary to that, apparent viscosity, yield point, gel strength, and consistency index are increased as temperature increases. The zeta potential of bentonite suspension in the presence of 50 mg/L cationic polyethylene imine followed by 10 mg/L anionic polyacrylamide were investigated at different temperature. The results showed that there is a direct relation between temperature and ζ potential. Potential energy profiles were constructed to investigate the relation between rheological and electrical properties. Potential energy profile at different bentonite suspensions gave a high‐repulsion potential energy between clay surfaces by increasing temperature, which means that the suspension stability improved. From the above results, it might be possible to say that the Egyptian clay suspension can give desired drilling mud properties using 6% clay suspension concentration treated with 50 mg/L polyethylene imine followed by 10 mg/L polyacrylamide at 80°C up to 24‐h aging time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Morphology and properties of the PA66/PC/silicone rubber composites
Authors: Chen Jun , Wu Wei , You Yi , Fan Wei , Chen Yujie 
Published: April 2010

AbstractThe research focused on the PA66/PC/silicone rubber composites. By adding silicone rubber as a toughener, the composites were prepared via dynamic vulcanization. The morphology and properties of the composites were characterized by FTIR, TEM, SEM, XRD, etc. The FTIR spectrum of the composites presented an increase of the 1730, 1240, and 1450 cm−1 that can be due to the CO interaction and the presence of the OCOO group, and this fact can mean the formation of the PA66–PC copolymer. The crosslinking of silicone rubber in the PA66/PC matrix formed the net‐like structure like semi‐IPN, which is propitious to enhance the interaction between PA66 matrix and PC and in further makes the PC particles embed in PA66 matrix closely. Novel composites are gained with outstanding mechanical properties and high temperature resistance, so the combine toughening by silicone rubber and PC is an ideal toughening system owing to the synergistic effect. In addition, the PA66/PC/silicone rubber/OMMT composite exhibits better flexile strength and flexile modulus without weakening other mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Optimizing preparation of NaCS–chitosan complex to form a potential material for the colon‐specific drug delivery system
Authors: Wang Ming‐Jun , Xie Yu‐Liang , Chen Zheng‐Jie , Yao Shan‐Jing 
Published: April 2010

AbstractA novel polyelectrolyte complex (PEC) formed by sodium cellulose sulfate (NaCS) and chitosan was prepared as a candidate material for colon‐specific drug delivery system. It was found in experiments that the properties of two raw materials and the process parameters, such as the degree of substitution (DS) and concentration of NaCS, the viscosity and concentration of chitosan, were very important factors on the properties of the final product—NaCS–chitosan‐PEC. The preparation of NaCS–chitosan complex was optimized by using response surface methodology to evaluate the effects of these parameters on the degradation properties of NaCS–chitosan in the simulated colonic fluid (SCF). The DS of NaCS was in the range from 0.2 to 0.6, the concentration of NaCS from 2 to 4% (w/v), the viscosity of chitosan from 50 to 550 mPa s, and the concentration of chitosan from 0.5 to 1.5% (w/v). A mathematical model was developed to describe the effect of these parameters and their interactions on the degradation of NaCS–chitosan complex. The optimum operation conditions for preparing NaCS–chitosan complex were determined to DS of NaCS of 0.2, the concentration of NaCS of 4.0% (w/v), chitosan viscosity of 327 mPa s, and the concentration of chitosan 0.5% (w/v), respectively. Validation of experiments with 5 confirmatory runs indicated the high degree of prognostic ability of response surface methodology. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Simultaneous algorithm for trajectory planning
Authors: Rubio Francisco J. , Valero Francisco J. , Suñer Jose Luis , Mata Vicente 
Published: April 2010

AbstractThis paper addresses the solution of smooth trajectory planning for industrial robots in environments with obstacles using a direct method, creating the trajectory gradually as the robot moves. The presented method deals with the uncertainties associated with the lack of knowledge of kinematic properties of intermediate via‐points since they are generated as the algorithm evolves looking for the solution. Several cost functions are also proposed, which use the time that has been calculated to guide the robot motion. The method has been applied successfully to a PUMA 560 robot and four operational parameters (execution time, computational time, distance travelled and number of configurations) have been computed to study the properties and influence of each cost function on the trajectory obtained.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Cyclization of Peptides through a Urea Bond: Application to the Arg‐Gly‐Asp Tripeptide
Authors: Schmidt Julien , Garambois Véronique , Rocheblave Luc , Martinez Jean , Pèlegrin André , Cavelier Florine , Vivès Eric 
Published: April 2010

AbstractVarious synthetic cyclopeptides bind different cellular proteins with high affinity and specificity. In this study, we designed a new series of cyclic tetrapeptides containing the RGD sequence, a ligand for the αvβ3 integrin receptor, in which the ring closure was performed through a urea bond between the α‐amino group of the peptide and either the α‐ or the ε‐amino group of an additional lysine. Interestingly, we showed that the urea‐closed peptide had a higher affinity for αvβ3 receptors than a reference pentacyclopeptide. Moreover, the synthetic strategy allows coupling of the resulting cyclic tetrapeptide through the carboxylic acid moiety of its lysine residue to fluorescent molecules or drugs. In addition, this strategy could be easily adapted for the cyclization of any other peptides.