bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of the relative importance of process factors on particle size distribution in suspension polymerization using a Bayesian experimental design technique
Authors: Vivaldo‐Lima Eduardo , Penlidis Alexander , Wood Philip E. , Hamielec Archie E. 
Published: September 2006

AbstractThe use of a Bayesian experimental design technique to determine the relative importance of factors that control particle size distribution (PSD) in suspension copolymerization of styrene and divinylbenzene is reported. Six factors and two responses are considered in this study. The experimental trials are of the two‐level factorial type designed with a Bayesian method. The experiments were carried out in a 5‐L pilot plant reactor. The matrix of variances of the parameter means (the prior knowledge) was estimated with the use of a preliminary compartment‐mixing (CM) model for PSD in suspension polymerization and our subjective judgement (process understanding). The responses, mean particle size and coefficient of variation, were calculated from distributions obtained with a Coulter particle counter. The results of this study provided the criteria needed to guide the future improvement of our CM‐PSD model in a balanced and effective way. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5577–5586, 2006
High‐resolution measurements of water permeability and solubility in microelectronic‐casing made of a hydrophobic polymeric composite
Authors: Zimrin Tomer , Haruvy Yaara Freeda , Margel Shlomo 
Published: September 2006

AbstractExposing the composite polymeric casing of integrated circuits (ICs) to water results in miniscule water absorption, followed by its permeation throughout the packaging, and component damage. Studying water penetration and solubility mechanisms in the IC casing is crucial for understanding water‐related damage mechanisms and protection against them. The main analytical challenge, hereafter, stems from the need to study miniscule water amounts (<0.5 wt %) capable of penetrating the casing, despite its hydrophobic nature. In this article, a TGA has been employed to study the water uptake kinetics in the casing, and to decipher the related water penetration mechanisms. High‐resolution measurements of water adsorption and desorption profiles were performed, followed by calculations of the related activation energies and solubility enthalpies. These data were correlated with a relatively new model that assigned the primary locales of the adsorbed water to the compatible filler–polymer interface. Thus, water permeability is related to molecules hopping between these sites. Finally, we have shown that for the IC casing in our study, the activation energy of water permeation is related to the binding energy of H2O onto the SiOSi groups at the fused‐silica‐filler surface, where they desorb, hop, and reabsorb. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4523–4527, 2006
Simulation of nonisothermal flow of melt during melting process of vibration‐induced polymer extruder
Authors: Feng Yan‐hong , Qu Jin‐ping , He He‐zhi , Jin Gang , Cao Xian‐wu , Song Jian 
Published: September 2006

AbstractA simplified 2D melt film model was established to simulate the nonisothermal melt flow during the melting process of the vibration‐induced polymer extruder of which the screw can vibrate axially. Since polymer has time‐dependent nonlinear viscoelastic characteristic with vibration force filed (VFF), a self‐amended nonisothermal Maxwell constitutive equation that can reflect the relaxation time spectrum of polymer was adopted. Using the 2D melt film model, melt films of two kinds of thickness representing different melting stages were simulated to investigate the influence tendency of the same VFF on the different melting stage. Special flow patterns and temperature distribution of melt in the melt film between the driving wall and the solid/melt interface with various vibration force fields were systematically simulated. It is found out that within a certain range of vibration strength, the application of vibration can optimize the time‐averaged shear‐rate distribution, improve the utilization efficiency of energy, and promote melting process; and the thinner the melt film is, the more intense the nonlinear viscoelastic response becomes with the same VFF; moreover, there exists optimum vibration strength to make the melting process fastest, which is in accord with the visualization experimental results. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5825–5840, 2006
Photo‐patterning of smart light‐modulation gel
Authors: Tsutsui Hiroaki , Akashi Ryojiro 
Published: September 2006

AbstractA novel method for fabricating desired patterns of smart light‐modulation gels, which consist of thermoresponsive N‐isopropylacrylamide (NIPAM) gel particles containing pigment, was developed. The patterns were fabricated by photo‐patterning of dispersion of colored NIPAM gel particles in photosensitive poly(vinylalcohol)‐styrylpyridinium solution. The pattern showed drastic color changes in response to the surrounding temperature changes. By repeated cycles of the patterning method, several independent patterns that contained different color particles were fabricated. In addition, a thermosensor array was also fabricated, which was constructed with independent patterns containing colored NIPAM gel having different color‐changing temperatures. The patterning method studied here is considered to have strong potential to extend the application field of the smart light‐modulation gels. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5351–5357, 2006
Synthesis and properties of novel deep red‐emitting copolymers based on a poly(p‐phenylenevinylene) derivative
Authors: Li Xianzhen , Zeng Wenjin , Xia Yangjun , Yang Wei , Cao Yong 
Published: September 2006

AbstractA series of novel copolymers based on a poly(p‐phenylenevinylene) (PPV) derivative with different content of narrow band‐gap unit 2,1,3‐benzoselenadiazolevinylene (BSeV) was prepared via Stille coupling reaction. The copolymers emit light from deep red to near‐infrared (NIR) depending on BSeV content in the copolymers. The electroluminescence (EL) emission peaked at 752 nm for the copolymer with the content of 30 mol % BSeV is among the longest reported so far for the PPV polymers. The best device performance is observed for the copolymer with 1 mol % BSeV content with external quantum efficiency (QEext) of 0.26% and CIE coordinate 0.65, 0.34 (x,y). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4321–4327, 2006
Kinetics study of radiation‐grafting of acrylic acid, acrylonitrile, and their mixture onto wool fabric
Authors: El‐Gendy E. H. , El‐Shanshoury I. A. 
Published: September 2006

AbstractThe effect of monomer concentration, exposure time, irradiation temperature, and weaving direction on the kinetics of grafting acrylic acid (AA), acrylonitrile (AN), and their mixture onto wool fabric has been studied at the dose rate of 1.38 Gy/s. The degree of grafting is found to depend on the methanol‐to‐water solvent ratio and fabric‐to‐liquor ratio. The grafting rate and rate constant are dependent on irradiation temperature, type of grafted monomer, and weaving direction. The grafting rates increase with the increase in irradiation temperature (276–308 K). The calculated activation energy is nearly the same (16.4–17.2 kJ mol−1) and the preexponential rate constant is dependent on the type of grafted monomer. The grafting of AA, AN, and their mixture are confirmed from the dyeing affinity of grafted fabrics towards Sandocryl Blue (SB), a basic dye. The formation of wool grafts and structural changes resulting from grafting were verified by using FTIR spectrometry and X‐ray diffraction analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4328–4340, 2006
Adsorption behavior and effectiveness of poly(N,N‐dimethylacrylamide‐co‐Ca 2‐acrylamido‐2‐methylpropanesulfonate) as cement fluid loss additive in the presence of acetone‐formaldehyde‐sulfite dispersant
Authors: Plank Johann , Brandl Andreas , Zhai Yanan , Franke Agnieszka 
Published: September 2006

AbstractA copolymer of N,N‐dimethylacrylamide and Calcium 2‐acrylamido‐2‐methylpropanesulfonate was synthesized by free‐radical copolymerization. Its performance as anionic fluid loss additive (FLA) was studied by measuring static filtration properties of oil well cement slurries at 27°C and 70 bar pressure, respectively. It was found that cement filter cake permeability and API fluid loss decrease with increasing FLA dosage. Filtrate analysis revealed a linear correlation between fluid loss and the amount of FLA adsorbed on the cement surface. FLA adsorption on cement was determined by total organic carbon (TOC) analysis in cement filtrate and confirmed by ζ‐potential measurement. According to environmental scanning electron microscopy (ESEM) investigations, FLA does not alter the filter cake structure. In the presence of an anionic acetone–formaldehyde–sulfite (AFS) polycondensate dispersant, fluid loss control from FLA decreased and cement filter cake permeability increased because AFS reduces the amount of FLA adsorbed. In comparison to FLA, AFS shows stronger adsorption on the cement surface and succeeds in the competition with FLA. The different adsorption behavior of the two polymers is the reason for limited compatibility of this admixture com bination. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4341–4347, 2006
Microstructure and glass‐transition temperature of novel star N‐SIBR
Authors: Wang Zhengsheng , Wang Yurong , Li Yang , Xu Hongde , Ren Yan , Zhang Chunqing 
Published: September 2006

AbstractIn this study, a polymeric N‐functionalized mutilithium (N‐M‐Li) compound was prepared from commercial divinylbenzene (DVB) and lithiohexamethyleneimine (LHMI), and star‐shaped copoly(styrene–butadiene–isoprene) was obtained by anionic polymerization using preformed N‐M‐Li as initiator, tetramethylethlenediamine (TMEDA) as polar modifier, and cyclohexane as solvent. The microstructure and the glass–transition temperature (Tg) of copolymers were characterized by 1H NMR and differential scanning calorimetry (DSC), respectively. It showed that the non‐1,4‐structure content and the Tg of copolymers increased with the increase of TMEDA dosage or the decrease of polymerization temperature; however, the effects of the initiator concentration and DVB dosage on them were not obvious. We also obtained the relationships between the non‐1,4‐structure content of copolymers and the Tg of copolymers respectively, and between the ln(T/Li) (TMEDA/N‐M‐Li, mole ratio) and the non‐1,4‐structure content of copolymers, as follows: Tg (°C) = 0.6258Cnon 1,4−55.93 and Cnon 1,4 = 20.79 ln K+59.11, where K is T/Li value. Therefore on the basis of experimental results, we realize polymer design according to our practical requirements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5848–5853, 2006
Partial substitution of cellulose by ring‐opening esterification of cyclic esters in a homogeneous system
Authors: Mayumi Ayaka , Kitaoka Takuya , Wariishi Hiroyuki 
Published: September 2006

AbstractPartially substituted cellulose derivatives were prepared by the regioselective derivatization of cellulose with cyclic esters (CEs), L‐lactide (LA), and ε‐caprolactone (CL), in a lithium chloride (LiCl)/N,N‐dimethylacetamide solvent. They were characterized by spectroscopic analyses, calorimetry, solvent solubility inspection, and an enzymatic degradability test. Fourier transform Raman spectra of the cellulose derivatives confirmed that the CE moieties were covalently introduced into cellulose molecules at their hydroxyl groups via ring‐opening esterification through the catalysis by LiCl. The 13C‐NMR analysis indicated that the ring‐opened CEs were regioselectively combined with cellulose C6‐OH. The CE portions were partially grafted on the cellulose backbone; the degree of substitution was ca. 0.5–0.7 and the degree of polymerization of grafted CEs was less than 3. Both cellulose derivatives were highly soluble in dimethylsulfoxide, which allows material fabrication. Some of the cellulose‐LA was soluble or swollen in water, while cellulose‐CL had poor affinity for water. Enzymatic degradation of cellulose‐CEs occurred immediately on cellulase treatment, even under mild conditions which are not able to hydrolyze commercial cellulose diacetate at all. Some cellulose derivatives displayed endothermic changes. The cellulose derivatives prepared in this study are expected to be used as cellulose‐based biomaterials with environmentally friendly features. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4358–4364, 2006
Structure and properties of polypropylene composites filled with magnesium hydroxide
Authors: Chen Xiaolang , Yu Jie , Guo Shaoyun 
Published: September 2006

AbstractSilane and silicone oil modified superfine magnesium hydroxide (MH) was filled into polypropylene (PP) as a flame retardant. The PP and flame‐retarded PP composites were studied for their mechanical properties and rheological behaviors by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), limiting oxygen index (LOI), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed that the addition of MH improved flame retardancy of PP/MH composites, but seriously deteriorated mechanical properties of the composites. Surface treatment of MH could significantly improve tensile and impact strength of PP/MH composite because of its enhanced interfacial adhesion between MH and PP matrix. DSC results showed that MH had heterogeneous nucleation effect on PP. Surface treatment of MH weakened its heterogeneous nucleation effect. POM results showed that the dispersion of MH particles played an important role in the crystalline morphology and spherulite size of PP crystals. TGA indicated that MH greatly enhanced the thermal stability of PP. The introduction of treatment agent further improved the thermal oxidative stability of the composite. According to LOI, silane‐treated MH greatly enhanced flame retardancy of PP/MH composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4943–4951, 2006
Mechanism of copper(II) adsorption by polyvinyl polyacrylate
Authors: Nakajima Akira , Sakai Naoko , Yamauchi Jun 
Published: September 2006

AbstractThe mechanism of copper adsorption by polyvinyl polyacrylate (PVPA) was examined using ESR and magnetic measurements. The copper adsorption by PVPA obeyed Langmuir adsorption isotherm with the maximum adsorption amounts of 4.17 mmol g−1 adsorbent, being larger than those of uranium adsorption. Though copper in the solution was completely adsorbed by the resin above pH 4, the ESR intensity was remained low level and only increased above pH 8. The ESR spectrum of Cu(II) ion in PVPA are axial type with tetragonally distorted octahedral symmetry, having parameters of g⊥ = 2.361, g⟂ = 2.057, |A⊥| = 14.0 m cm−1 (pH 5), and g⊥ = 2.329, g⟂ = 2.058, |A⊥| = 16.2 m cm−1, |A⟂| = 2.7 m cm−1 (pH 9). The absorption peaks originated from Cu(II)–Cu(II) dimer was also observed (pH 5). The paramagnetic susceptibility of PVPA adsorbed Cu(II) ion at pH 5 explained by the dimer model with |J| = 220 K. These results suggested that most of copper was adsorbed and formed dimer in PVPA, being similar to that in Cu(II)‐acetate monohydrate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5372–5377, 2006
Miscibility of styrene/unsaturated polyester quasibinary systems: Unsaturated polyester chemical composition and molecular weight influence
Authors: Buffa Fabián , Borrajo Julio 
Published: September 2006

AbstractUnsaturated polyester prepolymers were synthesized with different chemical compositions and molecular weights. Cloud‐point curves (CPC) were measured in St‐UP quasibinary solutions, showing UCST behavior in all cases. The miscibility of the first UP samples series in St comonomer was enhanced when AA chemical comonomer concentration in UP prepolymer increased. In the second series, UP prepolymer miscibility increased with the molecular weight up to a maximum and, after that, the miscibility decreased. A thermodynamic analysis of experimental CPCs was performed using the Flory‐Huggins (F‐H) theory for polydisperse polymer solutions. A simple relationship between the interaction parameter and the temperature inverse could fit the measured CPCs in wide concentrations and molecular weight ranges. In the temperature interval where this fit took place, the positive enthalpic contribution to the interaction parameters determined the miscibility dependence with temperature in both UP sample series. The St‐UP miscibility behavior was also correlated with UPs structural chemical parameters as: (a) the final HO and HOOC high polar groups concentration, (b) the chain backbone polar adipate and phthalate groups concentration, and (c) the UP size dependent mixing entropy. All these parameters are molecular weight dependent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6064–6073, 2006
Alginate‐coated chitosan membrane for guided tissue regeneration
Authors: Chen Ta Wei , Chang Shwu Jen , Niu Gregory Cheng‐Chie , Hsu Yun Ting , Kuo Shyh Ming 
Published: September 2006

AbstractChitosan membranes were first prepared by a thermally induced phase separation method and then alginate was coated on one side of the membranes by a modified dialysis apparatus to prepare alginate/chitosan membranes (A/C membranes). Electron spectroscopy for chemical analysis (ESCA), scanning electron microscope, and contact angle measurements were conducted to evaluate the surface characteristics. The mechanical strength, degradation behavior, and cell adhesion test were performed to evaluate the feasibility of using A/C membrane in guided tissue regeneration applications. The results revealed that alginates could effectively be coated onto the chitosan membrane. As observed in ESCA results, the N‐atomic emission peak was decreased from originally 6.2% on the untreated chitosan surface to 2% on the alginate‐treated surface. The contact angle decreased on the alginate‐modified side substantially, compared with the untreated side (from 88.4° to 34.2°). The A/C membrane had a higher water content of 71.8% in comparison to the chitosan membrane of 61.8%. Consequently, A/C membrane became stiffer and had a higher Young's modulus and strength. After a 30‐day in vitro shaking test, the weight of membranes was degraded to about 75% from the original. The 3T3 fibroblast cells showed less adhesion to alginate‐modified side as compared to the untreated chitosan‐side in cell adhesion test. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4528–4534, 2006
Poly(trimethylene terephthalate) nanocomposite fibers comprising different organoclays: Thermomechanical properties and morphology
Authors: Chang Jin‐Hae , Mun Mu Kyung , Kim Jeong‐Cheol 
Published: September 2006

AbstractPoly(trimethylene terephthalate) (PTT) nano composites were synthesized by in situ polymerization at high temperature with two thermally stable organoclays: 1,2‐dimethylhexadecylimidazolium‐montmorillonite (IMD‐MMT) and dodecyltriphenyl phosphonium‐MMT (C12PPh‐MMT). PTT hybrid fibers with various organoclay contents were melt‐spun at various draw ratios (DRs) to produce monofilaments. The thermomechanical properties and morphologies of the PTT hybrid fibers were characterized using differential scanning calorimetry, thermogravimetric analysis, wide‐angle X‐ray diffraction, electron microscopy, and mechanical tensile properties analysis. The nanostructure of the hybrid fibers was observed by both scanning and transmission electron microscopy, which showed that the clay layers were well dispersed into the matrix polymer, although some clusters or agglomerated particles were also detected. Unlike the hybrids containing IMD‐MMT, the clay layers of the C12PPh‐MMT hybrid fiber were more dispersed into the matrix polymer. The thermal stability and tensile properties of the hybrid fibers increased with increasing clay content for DR = 1. However, as DR increased from 1 to 9 the ultimate strength and initial modulus of the hybrid fibers with IMD‐MMT increased slightly whereas those of C12PPh‐MMT hybrid fibers decreased slightly. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4535–4545, 2006
Effect of formulation variables on the prediction of release from microparticles with experimental design
Authors: Luzardo‐Alvarez A. , Almeida‐Prieto S. , Fraga‐López F. , Otero‐Espinar F. , Rodriguez‐Núñez E. , Martinez‐Ageitos J. , Blanco‐Méndez J. 
Published: September 2006

AbstractDifferent formulations of triamcinolone acetonide (TA) encapsulated in microparticles (MPs) based on poly(D,L‐lactide‐co‐glycolide) (PLGA), poly(ϵ‐caprolactone) (PCL), and poly(methyl vinyl ether‐co‐maleic anhydride) (Gantrez AN119) blends were obtained by spray‐drying with a mixture experimental design. The goal of this study was to investigate the influence of the mixture composition, particle size, particle shape, enthalpy of melting (ΔHm) of PCL, enthalpy of depolymerization of PLGA, and glass‐transition temperature of Gantrez on drug release at pH 1.2 and 6.8. The presence of Gantrez in the MPs made PCL more amorphous because of the reduction of its ΔHm. The determination of the activation energy (Ea) associated with TA release from the MPs was used to calculate the fitting equation of the drug‐release profile, and subsequently, a thermodynamic (Arrhenius‐like) model was established. Drug release increased as Ea and ΔHm decreased. Our results suggest that this approach was capable of predicting in vitro TA release from these MPs, which allowed us to develop formulations with low‐release patterns at pH 1.2 and to modulate drug release at enteric pH. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4546–4553, 2006
Rheology of silicon carbide/vinyl ester nanocomposites
Authors: Yong Virginia , Hahn H. Thomas 
Published: September 2006

AbstractSilicon carbide (SiC) nanoparticles with no surface treatment raise the viscosity of a vinyl ester resin much more intensely than micrometer‐size SiC particles. An effective dispersant generally causes a reduction in the resin viscosity attributed to its surface‐active properties and thereby increases the maximum fraction of particles that can be introduced. This article assesses the rheological behavior of SiC‐nanoparticle‐filled vinyl ester resin systems with the Bingham, power‐law, Herschel–Bulkley, and Casson models. The maximum particle loading corresponding to infinite viscosity has been determined to be a 0.1 volume fraction with the (1 − ηr−1/2)–ϕ dependence (where ηr is the relative viscosity and ϕ is the particle volume fraction). The optimum fractional weight percentage of the dispersants (wt % dispersant/wt % SiC) is around 40% for 30‐nm SiC nanoparticles, which is much higher than 1–3% for micrometer‐size particles. SiC nanoparticles at a concentration of 9.2 wt % (0.03 volume fraction) cause a fourfold increase in the resin viscosity. The addition of a dispersant at the optimum dosage lowers the viscosity of SiC/vinyl ester suspensions by 50%. The reduction in the viscosity is substantial to improve the processability of SiC/vinyl ester nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4365–4371, 2006