bluuebunny/crossref_metadata_2025_split huggingface dataset:
Double Layer of Au(100)/Ionic Liquid Interface and Its Stability in Imidazolium‐Based Ionic Liquids
Authors: Su Yu‐Zhuan , Fu Yong‐Chun , Yan Jia‐Wei , Chen Zhao‐Bin , Mao Bing‐Wei 
Published: June 2009

AbstractRing any bells? The differential capacitance curve of Au(100) in neat [BMI]BF4 (BMI=1‐butyl‐3‐methylimidazolium) ionic liquid has a bell‐shaped feature (see picture). The adsorption of BMI+ shows a disorder–order transition and depends on the structure of the surface. Ordered adsorption in a micelle‐like structure stabilizes the underlying Au surface.magnified image
Activation of Hydrogen by Palladium(0): Formation of the Mononuclear Dihydride Complextrans‐[Pd(H)2(IPr)(PCy3)]
Authors: Fantasia Serena , Egbert Jonathan D. , Jurčík Václav , Cazin Catherine S. J. , Jacobsen Heiko , Cavallo Luigi , Heinekey D. Michael , Nolan Steven P. 
Published: June 2009

AbstractAn even split: In sharp contrast with the general behavior of Pd0complexes, [Pd(IPr)(PCy3)] is able to activate the HH bond. The resultingtrans‐[Pd(H)2(IPr)(PCy3)] is the first isolated mononuclear dihydride palladium compound. Its formation is supported by multinuclear NMR spectroscopy, density functional calculations, and X‐ray diffraction studies. The stability and reactivity of this new species are examined.magnified image
The Benzyne Aza‐Claisen Reaction
Authors: Cant Alastair A. , Bertrand Guillaume H. V. , Henderson Jaclyn L. , Roberts Lee , Greaney Michael F. 
Published: June 2009

AbstractAdding an aryne to a tertiary allylamine affords o‐allylaniline products of an aza‐Claisen rearrangement. The aryne simultaneously provides the π component for the rearrangement and the quaternization event that lowers the activation energy for the sigmatropic shift. The reaction was applied to the synthesis of medium‐ring benzannulated amines (see scheme).magnified image
Catalytic Microcapsules Assembled from Enzyme–Nanoparticle Conjugates at Oil–Water Interfaces
Authors: Samanta Bappaditya , Yang Xiao‐Chao , Ofir Yuval , Park Myoung‐Hawn , Patra Debabrata , Agasti Sarit S. , Miranda Oscar R. , Mo Zhi‐Hong , Rotello Vincent M. 
Published: June 2009

AbstractInvoluntary association: Anionic β‐galactosidase enzymes associate with positively charged Au nanoparticles to produce reduced‐charge conjugates, which assemble at oil–water interfaces to result in stable microcapsules (see picture). The microcapsules were formed quickly and showed high enzymatic activity, which makes them promising materials for biotechnology applications.magnified image
Cleaner Continuous Photo‐Oxidation Using Singlet Oxygen in Supercritical Carbon Dioxide
Authors: Bourne Richard A. , Han Xue , Poliakoff Martyn , George Michael W. 
Published: June 2009

AbstractHigh pressure under the spotlight: A new milliliter‐scale reactor is developed for using supercritical CO2 to perform continuous photo‐oxidation reactions. Changing from a traditional microliter‐scale batch reaction to 8 hours of reaction using the new reactor gives a 3000‐fold scale‐up of the oxidation of α‐terpinene (see picture).magnified image
Loading of Exponentially Grown LBL Films with Silver Nanoparticles and Their Application to Generalized SERS Detection
Authors: Abalde‐Cela Sara , Ho Szushen , Rodríguez‐González Benito , Correa‐Duarte Miguel A. , Álvarez‐Puebla Ramón A. , Liz‐Marzán Luis M. , Kotov Nicholas A. 
Published: June 2009

AbstractFeature film: Thin films made by exponential layer‐by‐layer growth display high diffusivity and can be readily infiltrated with inorganic nanoparticles. They can sequestrate molecular systems from solution as a function of the composition of their layers, while providing intense surface‐enhanced Raman scattering (SERS) signals (see picture).magnified image
Enantioselective Linchpin Catalysis by SOMO Catalysis: An Approach to the Asymmetric α‐Chlorination of Aldehydes and Terminal Epoxide Formation
Authors: Amatore Muriel , Beeson Teresa D. , Brown Sean P. , MacMillan David W. C. 
Published: June 2009

AbstractTime for SOme MOre: For the first time SOMO (singly occupied molecular orbital) activation has been exploited to allow a new approach to the α‐chlorination of aldehydes. This transformation can be readily implemented as part of a linchpin catalysis approach to the enantioselective production of terminal epoxides.magnified image
Iridium‐Catalyzed Asymmetric Isomerization of Primary Allylic Alcohols
Authors: Mantilli Luca , Gérard David , Torche Sonya , Besnard Céline , Mazet Clément 
Published: June 2009

AbstractNothing to sm(Ir)k at: Under appropriate reaction conditions, iridium hydride catalysts promote the isomerization of primary allylic alcohols. The best catalysts, like (R)‐1 (P green, O red, N blue, Ir yellow), deliver the desired chiral aldehydes with excellent enantioselectivity and good yields. Mechanistic hypotheses have been developed on the basis of preliminary investigations.magnified image
Self‐Coupling of a 4‐H‐Butatrienylidene Tungsten Complex
Authors: Semenov Sergey N. , Blacque Olivier , Fox Thomas , Venkatesan Koushik , Berke Heinz 
Published: June 2009

AbstractTungsten tryst: A 4‐H‐butatrienylidene complex of tungsten was successfully isolated and structurally characterized. It undergoes a unique self‐coupling, which leads to a dimer (see picture; P pink, O red) with a cross‐conjugated π system and with electrochemically and magnetically active metal centers.magnified image
Nano‐sized chalk‐protein deposits as filler of elastomers
Authors: Przepiórkowska Anita , Chrońska Karolina , Prochoń Miroslawa 
Published: June 2009

AbstractOne of the generally applied filler in rubber industry is commercial chalk—divided calcium carbonate. In aim to prevent from the agglomeration of calcium carbonate particles during mixing with rubber, calcium carbonate is modified. It rely on changing hydrophilic properties on hydrophobic properties acting surfactants as higher fatty acids, their salts, esters, higher aliphatic liquor, vegetable oils, or amine. The aim of present studies was to separate chalk and precipitating degraded proteins and fats about nano‐sized from two kind of environmentally noxious tannery effluents which came from processes of liming with degradation of hair structure. Obtained deposits were examined by FTIR spectroscopic, particles size measurements, zeta potential, microanalysis and then these deposits were used as fillers of rubber mixes such as NBR and XNBR. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Properties of alkoxysilane functionalized polycaprolactone/polydimethylsiloxane‐modified epoxy resin composites: Effect of curing temperature and compositions
Authors: Liu Pinggui , Song Jiangxuan , He Lihua , Liang Xingquan , Ding Heyan 
Published: June 2009

AbstractA series of epoxy resin composites containing different contents of alkoxysilane functionalized polycaprolactone/polydimethylsiloxane (PCS‐2Si) were prepared after curing with polyamidoamine curing agent at different temperatures. The effects of PCS‐2Si content and curing temperature on morphologies, solvent resistance, and surface properties of the composites were studied. The scanning electron microscope results showed that increasing the PCS‐2Si content and curing temperature caused the changes of miscibility between epoxy and modifier, leading to different morphologies. Other data from solvent swelling and surface tension of composites cured at the same temperature illustrated that the modified epoxy resins with higher content of PCS‐2Si had less crosslinked networks, but lower surface tension. At the same time, the composites cured at higher curing temperature generally had more resistance to chemicals and higher surface tension due to the formation of highly crosslinked networks. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermal decomposition of natural fibers: Global kinetic modeling with nonisothermal thermogravimetric analysis
Authors: Yao Fei , Wu Qinglin , Zhou Dingguo 
Published: June 2009

AbstractThe modeling of thermal decomposition process of ten natural fibers commonly used in polymer composite industry was performed by assuming a global model occurring within the entire degradation range with consideration of fiber as one pseudocomponent. Málek method with activation energy values previously obtained was applied to the modeling process. Careful calculation and evaluation indicated that, within an acceptable error limit of 5%, RO(n > 1) model can be used to describe the degradation process of most selected fibers well. The other kinetic parameters used include activation energy range of 160–170 kJ/mol; parameter n in RO(n > 1) = (1 − α)n of 3–4; and ln A between 35 and 42 ln s−1. Some condition limitations of the obtained model were also discussed. The model has practical significance in predicting fiber weight loss when the fiber is used in combination with engineering thermoplastics. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of expandable graphite and ammonium polyphosphate on the flame‐retardant and mechanical properties of rigid polyurethane foams
Authors: Meng Xian‐Yan , Ye Ling , Zhang Xiao‐Guang , Tang Pei‐Mei , Tang Jian‐Hua , Ji Xu , Li Zhong‐Ming 
Published: June 2009

AbstractIn this work, the effect of expandable graphite (EG) and ammonium polyphosphate (APP) on the flame retardancy and mechanical properties of the rigid polyurethane foam (RPUF) was studied. The results indicated that both EG and APP could effectively improve the flame retardancy of RPUF, while the retardancy of EG was better than APP. When the flame‐retardant loading was 15 wt %, the limited oxygen index (LOI) values of APP‐ and EG‐filled RPUF were 24.5 and 32 vol %, respectively. According to the LOI test, the optimal ratio of APP to EG in RPUF composites was 1 : 1 by weight, at which the LOI value of 15 wt % (APP + EG)/RPUF was 30.5 vol %. Thermal degradation test of RPUF composites by thermogravimetric analysis indicated that the addition of APP and EG to RPUF could lead to an increase in the amount of high‐temperature residue. Under the same conditions, the residue amount of EG/RPUF was less than that of APP/RPUF at the same temperature. Compression test and dynamic thermal mechanical analysis indicated that both the compressive strength and modulus decreased at a certain extent with the EG‐ or APP‐filled into RPUF, respectively, but with the mixture of EG and APP added into RPUF, the mechanical properties of these materials increased. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of low‐protein natural rubber latex: Effect of polyethylene glycol
Authors: Abhilash G. , Sabharwal S. , Dubey Abhinav , Paul Jose , John Honey , Joseph Rani 
Published: June 2009

AbstractLow‐protein content natural rubber latex was produced by using a nonionic surfactant‐polyethylene glycol (PEG). Extractable protein content of natural rubber latex was found to decrease with PEG treatment and reduction increased with increase in the molecular weight of PEG. The low‐protein latex samples were characterized by tensile testing, Fourier transform infrared and thermogravimetric analysis. The results have shown 35% reduction in the extractable protein content, without any compromise on the mechanical properties of the latex; however, thermal stability of low‐protein latex was found to be reduced marginally with PEG treatment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Properties of poly(vinyl chloride) and polyesteramides blends
Authors: Kalousková Radka , Markvart Ludìk , Kredatusová Jana , Brožek Jiří 
Published: June 2009

AbstractBlends of poly(vinyl chloride) (PVC) and polyesteramides (PEA), based on ε‐caprolactam and ε‐caprolactone, were prepared to improve the notch impact strength of PVC. Miscibility of components was assessed from glass transition temperature and is limited by the amount of PEA in the blend and by the content of ε‐caprolactam structural units in PEA. The effects of the content and type of PEA on their thermal stability and notched impact strength were also investigated. The impact strength of the PVC blends reaches its maximum at an equimolar lactam to lactone units ratio in PEA; it decreases with increasing content of PEA in the blend. An admixture of a small amount of poly(ε‐caprolactam) as a compatibilizer made it possible to prepare PEA‐rich PVC blends, exhibiting twice as high notch impact strength, as compared to pure PVC. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Organic and aqueous compatible polystyrene–maleic anhydride copolymer ultra‐fine fibrous membranes
Authors: Cécile Corine , Hsieh You‐Lo 
Published: June 2009

AbstractPolystyrene–maleic anhydride copolymer (PSMA, Mv= 700 kDa) was synthesized and efficiently processed into 400 to 600 nm diameter fibers via electrospinning from either 20 wt % dimethylformamide or 25 wt % dimethylsulfoxide solution. Crosslinking of PSMA was effective by adding glycerol and poly(vinyl alcohol) (PVA) (Mw = 31–50 kDa) in the dimethylformamide and dimethylsulfoxide solutions, respectively. The PSMA fibers containing glycerol at 29.4 mol% were auto‐crosslinked whereas those with 12.9 mol% (2 wt %) glycerol and 15.4 mol% (0.75 wt %) PVA required heating to induce intermolecular esterification. Heat‐induced crosslinking with glycerol was more effective in rendering the PSMA fibrous membranes insoluble in all solvents whereas that with PVA remained soluble in most solvents except for acetone and tetrahydrofuran. The crosslinked fibrous membranes had improved thermally stability and retained physical integrity upon exposure (2 hr at 40°C) to carbon disulfide, the solvent for Friedel‐Craft reactions of the styrene moiety. Hydrolysis (0.01N NaOH) of the auto‐crosslinked fibrous membrane significantly improved its hydrophilicity by reducing the water contact angles from 90.6° to 62.5° in a matter of seconds. These ultra‐high specific surface PSMA fibrous membranes have shown superior organic and aqueous solvent compatibility to be used as highly reactive and easily retrievable supports for solid‐phase synthesis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
High shear strain rate rheometry of polymer melts
Authors: Kelly A. L. , Gough T. , Whiteside B. R. , Coates P. D. 
Published: June 2009

AbstractThe rheology of a range of polymer melts has been measured at strain rates above those attained during conventional rheometry using an instrumented injection molding machine. Deviations from shear thinning behavior were observed at high rates, and previously unreported shear thickening behavior occurred for some of the polymers examined. Measured pressure and volumetric throughputs were used to calculate shear and extensional viscosity at wall shear strain rates up to 107 s−1. Parallel plate rheometry and twin bore capillary rheometry were used to provide comparative rheological data at low and medium shear strain rates, respectively. Commercial grades of polyethylene, polypropylene, polystyrene, and PMMA were studied. Measured shear viscosity was found to follow Newtonian behavior at low rates and shear thinning power law behavior at intermediate strain rates. At shear strain rates approaching or above 106 s−1, shear viscosity reached a rate‐independent plateau, and in some cases shear thickened with further increase in strain rate. A relationship between the measured high strain rate rheological behavior and molecular structure was noted, with polymers containing larger side groups reaching the rate‐independent plateau at lower strain rates than those with simpler structures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of processible doped polyaniline‐polyacrylic acid composites
Authors: Gupta Bhavana , Prakash Rajiv 
Published: June 2009

AbstractProcessible composites of emeraldine salt form of polyaniline (PANI) with polyacrylic acid (PAA) are synthesized and studied for their structural, electrical, mechanical, thermal, and electrochemical properties. The processible conducting composites of various weight percentage from 20 wt % to 90 wt % (of PANI) have been prepared by mixing the PANI and PAA under vigorous stirring and sonication conditions. Self‐standing films of electroactive homogeneous composites are obtained by solution casting method. A significant improvement in processibility, crystallinity, and thermal stability is observed in the composites; however, the electrical conductivity decreased remarkably as the percentage of PANI is decreased in the composites. The 60 wt % PANI‐PAA composite showed crystalline structural property with orthorhombic crystal system and cell parameters as a = 5.93Å, b = 7.57Å, and c = 10.11Å. The 60 wt % PANI‐PAA composite also showed better thermal stability and highest capacitance amongst all the composites and used as an active material for development of electrochemical capacitors (parallel plate assembly). The processible composites based electrochemical capacitors using 0.5 M NaClO4‐Acetonitril electrolyte showed super capacitance with ease in fabrication and cost effectiveness in comparison to other similar materials based capacitors. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and characterization of isotropic polyurethane magnetorheological elastomer through in situ polymerization
Authors: Wu Jinkui , Gong Xinglong , Chen Lin , Xia Hesheng , Hu Zaiguo 
Published: June 2009

AbstractThe highly filled isotropic polyurethane (PU) elastomer with a magnetorheological (MR) effect was prepared through an in situ polycondensation method. The carbonyl iron particles were treated by coupling agents and then the dispersions of polyol/carbonyl iron particles was prepared by a ball milling process. The dispersion problem of magnetizable particles at a high content in PU matrix was tried to overcome by the combination of surface modification, ball milling, and in situ polymerization. The microstructure and properties of the composite were examined in detail. With increasing the content of carbonyl iron particles, the degree of phase separation of PU increased and the glass transition temperature (Tg) of PU soft segment decreased. Highly filled carbonyl iron particles led to the decrease in the thermal stability of PU matrix, especially in the heating air atmosphere. The MR effect appeared when the content of carbonyl iron particles was higher than 50 wt %, and became relatively pronounced at a 70 wt % of carbonyl iron content. The mechanical properties of PU MR elastomers were deteriorated significantly at a high content of carbonyl iron. Surface modification of carbonyl iron particles can improve the mechanical properties to some extent; however, it was also found that surface modification led to a decrease in the MR effect because of the improved interfacial adhesion. The MR test showed that the maximum absolute MR effect and relative MR effect of PU composite were ∼ 0.31 MPa and ∼ 8.1% at 1 Hz and 400 mT with 70 wt % of carbonyl iron, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of the incorporation of fine calcium carbonate particles on the impact strength of polypropylene/polystyrene‐block‐poly(ethylene butene)‐block‐polystyrene blends
Authors: Hikasa Shigeki , Nagata Kazuya , Miyahara Kenji , Izumi Toshihiro , Suda Toshiya , Toyohara Asami , Kato Atushi , Nakamura Yoshinobu 
Published: June 2009

AbstractThe Izod impact strength of two kinds of ternary composites was investigated. One consisted of polypropylene (PP), the triblock copolymer polystyrene‐block‐poly(ethylene butene)‐block‐polystyrene (SEBS), and calcium carbonate (CaCO3) particles, and the other consisted of PP, carboxylated SEBS (C‐SEBS), and CaCO3 particles. The mean size of the CaCO3 particles was about 160 nm. According to scanning electron microscopy observations, the composite with SEBS showed a morphology in which SEBS domains and CaCO3 particles were independently dispersed in the PP matrix. On the other hand, the composite with C‐SEBS showed a morphology in which CaCO3 particles were encapsulated by C‐SEBS; that is, a core–shell structure was formed. The Izod impact strength of the composite with SEBS was higher than that of the composite with C‐SEBS and the PP/SEBS and PP/C‐SEBS binary blends. According to observations of the fractured surface, the stress‐whitened area was larger in the composite with SEBS than in the composite with C‐SEBS and the PP/SEBS and PP/C‐SEBS binary blends. The toughening mechanism of the composite, using nanometer‐sized CaCO3 particles in combination with SEBS, was examined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Strain effect on recovery behaviors from circular deformation of natural rubber vulcanizate
Authors: Choi Sung‐Seen , Han Dong‐Hun 
Published: June 2009

AbstractThe recovery behaviors of vulcanized natural rubber from circular deformation were studied by varying sample length to investigate the influence of the degree of applied strain to the sample. The stress and strain varied uniformly across the thickness of the sample, and the degree of applied stress and strain to the sample decreased with increasing the sample length. The linear sample was made into a circular form and thermally aged in a convection oven. The recovery was measured after removing from the circular deformation. The recovery increased by decreasing the sample length. The difference in recoveries of the samples with different lengths reduced at high temperature. The short sample had higher heat‐resisting property for recovery than the long sample. The experimental results were explained by the rearrangement and stabilization of the deformed rubber chains as well as the crosslink density change. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of surface esterification with octenyl succinic anhydride on hydrophilicity of corn starch films
Authors: Zhou Jiang , Ren Lili , Tong Jin , Ma Yunhai 
Published: June 2009

AbstractSurface of corn starch films was modified through esterification using octenyl succinic anhydride as reactant. Physical properties of the films, moisture absorption, and water contact angle were measured to characterize the effect of the surface esterification modification. The influences of the concentration of alkaline aqueous solution for activating starch, reaction temperature, and time were investigated. It was found that the pretreatments with 1.0% or 2.0% NaOH aqueous solution and reacting at 35°C for 6 h gave rise to films possessing higher water contact angle, lower equilibrium moisture content, and moisture absorption rate at 95% relative humidity (RH). After the surface esterification modification, the equilibrium moisture content of the starch film decreased up to 29% at 95% RH and the surface water contact angle of the film increased up to 83%. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and Anti‐Inflammatory Activity of Novel (4‐Hydroxyphenyl)(2,4‐dimethoxyphenyl) Methanone Derivatives
Authors: Vinaya Kambappa , Naika Raja , Kumar Channappillekoppal S. Ananda , Ranganath Somasagara R. , Prasad Salekoppal B. Benaka , Krishna Venkatarangaiah , Rangappa Kanchugarakoppal S. 
Published: June 2009

AbstractIn the scope of the research program aiming to perform the synthesis and pharmacological evaluation of novel possible anti‐inflammatory compounds, in this manuscript, we report the synthesis of novel carboxamide 9a‐d and thioamide 10a‐d derivatives from the benzophenone and piperidine nucleus. Variation in the functional group at the N‐terminal of piperidine led to two sets of compounds, bearing the carboxamide and thioamide, respectively. The characterization of this new class of compounds was performed with 1H‐NMR, LC‐MS, IR, and elemental analysis. The newly synthesized compounds were screened for their anti‐inflammatory activity by carrageenan‐induced foot pad oedema assay and were compared with a standard drug. All the compounds exhibited anti‐inflammatory activity at the dose of 30 mg/kg p.o. with varying degree from 52 to 67% inhibition of oedema. The compounds 9d and 10d with dichloro and fluoro substitution showed more potent activity at 30 mg/kg p.o. than the standard drug.