bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and characterization of polyacrylic acid/dexy 85 and polyacrylic acid/gum arabic adducts
Authors: Abo‐Shosha M. H. , Ibrahim N. A. , Allam E. , El‐Zairy M. R. , El‐Zairy E. M. 
Published: June 2006

AbstractPolyacrylic acid/gum arabic or polyacrylic acid/dextrin (PAA/GA or PAA/D) adducts were prepared by free radical polymerization of highly concentrated, partially neutralized AA using Na2S2O8/Na2S2O3redox system in the presence of GA or D. Optimum reaction conditions, viz., AA, 6.76 mol/L; Na2S2O3, 26.87 × 10−3mol/L; Na2S2O8, 34.9 × 10−3mol/L; degree of neutralization, 20%; temperature, 90°C; and time 30 min, were utilized in preparing two adducts of each substrate (GA or D) at two liquor ratios (LRs; 1.25/1 and 6.3/1L/K). The four adducts formed, viz., PAA/GA1, PAA/GA2,PAA/D1, and PAA/D2(where 1 and 2 refer to the low and high LR, respectively) were found to be water soluble at all proportions. IR spectrum of these adducts confirmed the introduction of the COOH group onto their structures. Rheological properties of 7% aqueous solutions of these adducts, including Na‐alginate (Alg), showed that all are characterized by a non‐Newtonian, shear‐thinning, thixotropic behavior. Within the range of shear rate studied, the apparent viscosities of these solutions followed the descending order: PAA/D2> PAA/D1> Alg > GA1= PAA/GA2. Completing neutralization (Na form) of adducts to 100% results in a remarkable enhancement of their apparent viscosities, so that they follow the descending order, depending on the shear rate:equation imageequation imageequation image© 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4290–4300, 2006
Effects of chitosan addition to DMEU‐processed cotton fabrics for adsorbing metallic ions in waste water
Authors: Hsieh Sung Huang , Huang Chih Huang , Chiu Shun Pin 
Published: June 2006

AbstractThis study examines the effects of adding chitosan to the curing treatment of cotton fabrics, using dimethylolethyleneurea as a crosslinking reagent; in particular, how the adsorption of the processed cotton fabrics for metallic ions is influenced. Different concentrations of added chitosan, different curing temperatures and time, as well as different adsorption times and temperatures were examined. The cotton fabrics studied were compared with other adsorptive materials, and also, were examined by Fourier Transform Infrared Analysis (FTIR), Scanning Electronic Microscope (SEM), and Thermal Gravity Analysis (TGA) to study the crosslinkage reaction. The experimental results were as follows: the adsorption of copper and zinc ions increases as chitosan concentration increases, with the best adsorption when chitosan concentration is 0.5%; the adsorption of copper and zinc ions increases as the curing temperature rises, with the best adsorption at 140°C; the adsorption increases with longer curing time, with the best adsorption at 6 min after the processing begins. For adsorption of zinc ions, the cotton fabrics containing chitosan have better adsorption than pure chitosan, but worse adsorption than activated carbon. For the adsorption of copper ions, chitosan is the best, processed cotton fabrics are the second, and activated carbon is the poorest. The adsorption of these two kinds of ions increases with the longer time and higher temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4440–4445, 2006
Relationship between structure and properties of modified potato starch biodegradable films
Authors: Cyras Viviana P. , Tolosa Zenklusen María C. , Vazquez Analía 
Published: June 2006

AbstractPotato starch was gelatinized in the presence of water and varying amounts of glycerol at 90°C. Starch/glycerol films were prepared by casting with water. The addition of glycerol produces a decrease in the crystallinity of the starch in the films. Starch was acetylated (with acetic acid and anhydride) and maleated (with maleic anhydride). Differential scanning calorimetric analysis revealed decrease in the glass transition temperature (Tg) with the chemical modification. The starch modification on the equilibrium moisture content was determined at 25°C. The esterifications produce a decrease in the maximum moisture sorption. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4313–4319, 2006
Separation of metal ions by water‐insoluble polymers containing sulfonic/sulfonate groups
Authors: Rivas Bernabé L. , Muñoz Carla 
Published: June 2006

AbstractA water‐insoluble polymer, poly(sodium 4‐styrene sulfonate), was synthesized by radical polymerization at different amounts (2, 4, 6, and 8 mol %) of crosslinking reagent (CR). At the lowest CR level (2 mol %), only a water‐soluble polymer is obtained, and consequently it could not be studied as resin. The polymerization yield ranged from 82.6 to 91.6%. The resin is characterized by FTIR spectroscopy, thermal analysis, and scanning electron microscopy. The metal ion affinity is studied for the cations: Hg(II), Cd(II), Zn(II), Pb(II), Cr(III), and Al(III) with a batch equilibrium procedure under different experimental conditions. The metal ion affinity increased as the pH increased. At pH 5, the resin showed an affinity greater than 97% for all metal ions. Hg(II) showed the highest retention value at pH 2. The maximum retention capacity is determined at optimum pH for Hg(II), Cd(II), Pb(II), and Zn(II). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4328–4333, 2006
Enhanced gas separation properties by using nanostructured PES‐Zeolite 4A mixed matrix membranes
Authors: Huang Zhen , Li Yi , Wen Rui , May Teoh May , Kulprathipanja Santi 
Published: June 2006

AbstractThe polymer–zeolite mixed matrix membranes were fabricated by incorporating nanosized or microsized zeolite 4A into polyethersulfone. A comparison of zeolite 4A nanocrystals and microcrystals was made by using SEM, XRD, N2 adsorption–desorption measurements. Zeolite particles were well‐distributed in the polymer phase, as reflected by the SEM images. The effects of the zeolite 4A particle size on the gas permeation performance were studied. Experimental results demonstrate that mixed matrix membranes exhibit decreased gas permeabilities due to the barrier effect of zeolite particles. The obtained permselectivity is greatly enhanced for He/N2, H2/N2, He/CO2, and H2/CO2 gas pairs, especially for nanosized zeolite 4A mixed matrix membranes. The gas permeation performance difference is observed between the nanostructured and microstructured membranes, which is attributed to a combined effect of different zeolite composition and different particle size. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3800–3805, 2006
Thermal cure of phenylethynyl‐terminated AFR‐PEPA‐4 imide oligomer and a model compound
Authors: Li Yuntao , Morgan Roger J. 
Published: June 2006

AbstractThe thermal cure reactions of phenylethynyl terminated AFR‐PEPA‐4 oligomer and a model compound N‐phenyl‐[4‐(phenylethynyl) phthalimide] were investigated. The kinetics analysis of the thermal cure of AFR‐PEPA‐4 was determined using DSC, with modified DiBenedetto equation. The activation energy of thermal cure reaction of AFR‐PEPA‐4 oligomer is 34.1 kcal/mol with the kinetic order of one, when the reaction conversion is less than 80%. The activation energy of thermal reaction of N‐phenyl‐[4‐(phenylethynyl) phthalimide] is 41.5 kcal/mol with the kinetic order of 0.95. The cure reaction of AFR‐PEPA‐4 imide oligomer can be described as a fast first‐order reaction stage for the formation of polyenes followed by a slow diffusion‐controlled crosslinking reaction stage. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4446–4453, 2006
Cocrystallization mechanism of poly(3‐hexyl thiophenes) with different amount of chain regioregularity
Authors: Pal Susmita , Nandi Arun K. 
Published: June 2006

AbstractThe overall crystallization rates of poly (3‐hexyl thiophene) (P3HT) cocrystals with different amount of regioregularity of the components are measured using differential scanning calorimetry (DSC). Two pairs of cocrystals with varying compositions of the component polymers (viz P3HT(R) (regioregularity 92 mol %)/P3HT‐2 (regioregularity 82 mol %), and P3HT‐2/P3HT‐1 (regioregularity 75 mol %)) are used. The crystallization rate at the same isothermal crystallization temperature (Tc) decreases with increasing regioregularity. The low Avrami exponent values (0.15–1.0) in all the samples suggest the presence of rigid amorphous portion, which cannot diffuse out quickly from the crystal growth front (soft impingement). Analysis of crystallization rate using Laurintzen–Hoffman (L–H) growth rate theory indicates Regime I to Regime II transition in all the samples. The product of lateral and end surface energy values (σσe) increases gradually with increasing regioirregularity in the blend. Analysis of σ values indicates chain extension of the components in the melt of the blend and the entropy of activation (ΔSI–II) of the cocrystals are higher than those of the components. The entropy of cocrystallization (ΔSc) values are 1–2.4 e.u for P3HT(R)/P3HT‐2 system and 0.5–1 e.u for P3HT‐2/P3HT‐1 system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3811–3820, 2006
Plasma modification of cellulose fibers for composite materials
Authors: Morales J. , Olayo M. G. , Cruz G. J. , Herrera‐Franco P. , Olayo R. 
Published: June 2006

AbstractComposites of natural fibers and thermoplastics can be combined to form new enhanced materials. One of the problems involved in this type of composites is the formation of chemical bonds between the fibers and the polymers at the interface. This work presents a study where low energy glow discharge plasmas are used to functionalize cellulose fibers implanting polystyrene between the fibers and the matrix that improve the adhesion of both components. The interface of polystyrene was synthesized by continuous and periodic glow discharges on the surface of the cellulose fibers. The results show that the adhesion in the fiber–matrix interface increases with time in the first 4 min of treatment. However, at longer plasma exposures, the fiber may be degraded reducing the adhesion with the matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3821–3828, 2006
Blue light‐emitting poly(p‐phenylenevinylene) derivative with oxadiazole and carbazole pendant groups
Authors: Mikroyannidis John A. 
Published: June 2006

AbstractA blue light‐emitting statistical poly(p‐phenylenevinylene) (PPV) copolymer with hole‐transporting carbazole and electron‐transporting oxadiazole pendant groups attached to the kinked m‐terphenyl unit was prepared by Heck coupling between 1,4‐divinylbenzene and dibromides. The latter were synthesized through pyrylium salts. The polymer had optical band gap of 2.89 eV and emission maximum at 446 nm in THF solution and 434 nm in thin film. It showed a pure blue emission with no aggregates or excimers formed even in solid state because of the long and bulky pendant groups. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3842–3849, 2006
Molecularly imprinted polymer membranes for substance‐selective solid‐phase extraction from aqueous solutions
Authors: Zhu Xiaolan , Su Qingde , Cai Jibao , Yang Jun , Gao Yun 
Published: June 2006

AbstractThin‐layer molecularly imprinted polymer (MIP) composite membranes for selective binding of monocrotophos (MCP) pesticide from aqueous solutions were developed. The procedure was based on commercially available membrane modules that were rinsed with prepolymerization imprinting mixtures. After the in situ polymerization and generation of MIP films on the membranes within the modules, the membranes were evaluated in terms of affinity toward the target molecule MCP. MIP membranes with different porogens and different monomers on Nylon‐6 membranes were prepared. It was shown that MIP membranes synthesized with methacrylic acid as monomer and toluene as porogens on the Nylon‐6 membranes provided a highly selective binding of MCP from aqueous solutions under the optimized elution conditions. With the novel surface modification technique, the low nonspecific binding properties of the microfiltration membrane could successfully be combined with the receptor properties of molecular imprints, yielding substance‐specific MIP composite membranes. The high affinity of these synthetic membranes to MCP pesticide together with their straightforward and inexpensive preparation could be applied in a fast preconcertration step, solid‐phase extraction, by a simple microfitration for the determination of MCP in water. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4468–4473, 2006
Dipolar chains and 2D aligned stripes of polymer‐coated magnetic iron colloid
Authors: Yan Lifeng , Shen Sui , Li Wan , Wang Xiaoping 
Published: June 2006

AbstractStudies on the self‐assembly of core–shell magnetic nanospheres under or without an external magnetic field are the subject of intense research. It is believed that after being coated by organic molecules, the magnetic nanoparticles can still have chance to form chain‐like structure driven by the dipole–dipole interactions while the coated shell minimizes the effect of Van der Waals attractions. However, still there are no direct experimental observations for polymer‐modified magnetic colloids sized hundreds of nanometers. In this article, PEG‐ and PSt‐coated Fe2O3 nanospheres were synthesized and their self‐assembly behaviors were studied. MFM and TEM measurements reveal that the prepared spheres owning a core–shell structure. Under zero magnetic field, a direct observation of chain‐like structure was achieved for the PEG‐coated magnetic colloids. For the PSt‐modified magnetic spheres, there formed a 2D aligned stripes pattern at the surface of mica when the suspending of sample was dried under an external magnetic field. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4211–4215, 2006
High PVC film‐forming composite latex particles via miniemulsification, part 1: Preparation
Authors: Al‐Ghamdi Ghurmallah H. , Sudol E. David , Dimonie Victoria L. , El‐Aasser Mohamed S. 
Published: June 2006

AbstractMiniemulsification technology was used to encapsulate TiO2 particles inside a styrene/n‐butyl acrylate copolymer with high loading levels (11 to 70% PVC (pigment volume concentration)). In this approach, a St/BA copolymer dissolved in toluene in the presence of a costabilizer (hexadecane) was mixed with a dispersion of TiO2 particles in toluene and sonified, and then emulsified in an aqueous surfactant solution by sonification. The effect of sonification time on both the dispersibility of the TiO2 particles in the presence of the copolymer and hexadecane and on the encapsulated particle size was investigated. Particle size analysis by dynamic light scattering showed that these composite latexes are quite stable. It was also found that as the TiO2 loading increased from 11 to 43% PVC, the particle size of the TiO2 dispersion decreased while the polymer‐encapsulated TiO2 particle size increased. The effect of surfactant concentration (sodium lauryl sulfate, SLS) on the encapsulated particle size was investigated using four different SLS concentrations in the 11% PVC system. The results showed that as the SLS concentration increased the particle size decreased, as expected. Also it was found that the minimum surfactant concentration that gives stable encapsulated TiO2 particles is above 10 mM SLS. The role of HD in the recipe was studied for an artificial latex containing no TiO2 and one prepared at 11% PVC, in terms of particle size before and after solvent stripping, and its effect on the Tg. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4504–4516, 2006
Effect of various plasticizers on the transport properties of hexanoyl chitosan‐based polymer electrolyte
Authors: Winie Tan , Arof A. K. 
Published: June 2006

AbstractHexanoyl chitosan that exhibited solubility in tetrahydrofuran was prepared by acyl modification of chitosan. Films of hexanoyl chitosan‐based polymer electrolyte were prepared by the technique of solution casting. Ethylene carbonate, propylene carbonate, and diethyl carbonate with different dielectric constants were employed as the plasticizing solvents and lithium trifluoromethanesulfonate (LiCF3SO3) was used as the salt. The importance of dielectric constant affecting conductivity and transport properties of hexanoyl chitosan:LiCF3SO3 electrolytes have been examined in the present study. An enhancement in the ionic conductivity has been found on plasticization, and the magnitude of conductivity increment strongly depended on the dielectric constant of the plasticizer. Transport properties such as activation energy and charge carrier concentration have been calculated to obtain information that may be used to elucidate the mechanism of conductance. In addition to conductivity studies, thermal studies and transference number measurements were performed to correlate the phase structure and diffusion phenomena to the conductivity behavior of hexanoyl chitosan‐based polymer electrolyte. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101:4474–4479, 2006
Fundamental parameters affecting electrospinning of PAN nanofibers as uniaxially aligned fibers
Authors: Jalili Rouhollah , Morshed Mohammad , Ravandi Seyed Abdolkarim Hosseini 
Published: June 2006

AbstractElectrospinning with a collector consisting of two pieces of electrically conductive substrates separated by a gap has been used to prepare uniaxially aligned PAN nanofibers. Solution of 15 wt % of PAN/DMF was used tentatively for electrospinning. The effects of width of the gap and applied voltage on degree of alignment were investigated using image‐processing technique by Fourier power spectrum method. The electrospinning conditions that gave the best alignment of nanofibers for 10–15 wt % solution concentrations were experimentally obtained. Bundles like multifilament yarns of uniaxially aligned nanofibers were prepared using a new simple method. After‐treatments of these bundles were carried out in boiling water under tension. A comparison was made between the crystallinity and mechanical behavior of posttreated and untreated bundles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4350–4357, 2006
Physical properties of electron beam irradiated poly(vinyl butyral) composites with carbamate, imidazole, and tetrazolium dye
Authors: Said Hossam M. , Ali Z. I. , Ali Hussein E. 
Published: June 2006

AbstractFilms of poly(vinyl butyral) composites with triphenyl tetrazolium chloride dye (TTC) and the antioxidant nickel dibutyl dithiocarbamate (NBC) or 2‐mercaptobenzimidazole (MBI) were prepared by the solution casting method using butyl alcohol as a solvent. The effect of various doses of electron beam irradiation (50–200 kGy) on color response, thermal, and mechanical properties were investigated. The color measurements showed that the films of the different composites possessed a high sensitivity to electron beam irradiation, in which the nearly colorless films were changed to deep red color, which can be easily detected by visual observations. In addition, the change in color depends on irradiation dose and the contents of the TTC dye. Moreover, the presence of the antioxidants NBC or MBI has no effect on the development of color. However, PVB/TTC and PVB/TTC/MBI composites showed high regular change in color as a function of irradiation dose. The thermogravimetric analysis used to study the thermal stability indicated that PVB/TTC composites either before or after electron beam irradiation are thermally more stable than neat PVB polymer. The presence of the antioxidants NBC or MBI offered protection to PVB/TTC composites against decomposition or oxidative degradation resulted from irradiation. Blending unirradiated PVB with TTC dye, mixture of TTC and NBC, and mixture of TTC and MBI reduced the tensile strength by 4, 20, and 17% upon blending, respectively. However, the reduction in tensile strength of the entire composite films (∼7% based on the initial value) upon exposure to a dose of 50 kGy is acceptable for practical applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4358–4365, 2006
Investigation on preparation and property of nano‐CaCO3/PP masterbatch modified by reactive monomers
Authors: Zhidan Lin , Zishou Zhang , Zhenzhen Huang , Kancheng Mai 
Published: June 2006

AbstractNano‐CaCO3/polypropylene (PP) masterbatch containing above 80 wt % nano‐CaCO3 was prepared by nano‐CaCO3 coated PP modified by reactive monomers. The chemical interaction, crystallization and melting behavior, thermal stability, morphology, and surface contact angle of masterbatch were investigated with IR, DSC, TEM, TGA, ESCA, and surface contact angle. The results indicated that nano‐CaCO3 was coated by PP graft copolymers in the masterbatch modified by reactive monomers. The graft ratio and crystallization and melting behavior of PP in the masterbatch depended on the type and content of reactive monomer. The crystallization temperatures of masterbatch modified by reactive monomer is methyl methacrylate > butyl acrylate > methyl acrylate ≈ mixture of acrylic acid and styrene > unmodified ≈ maleic anhydride ≈ acrylic acid > styrene. Modification by reactive monomer increased the thermal stability and surface contact angle of masterbatch. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3907–3914, 2006
The conversion of calcium alginate fibers into alginic acid fibers and sodium alginate fibers
Authors: Qin Yimin , Hu Huiqun , Luo Aixiang 
Published: June 2006

AbstractAlginate is a natural polymer extracted from brown seaweeds. Over the last two decades, alginate fibers have become well established in the wound management industry where their ion exchange and gel forming abilities are particularly useful in the treatment for exuding wounds. Alginate fibers are commonly made by extruding sodium alginate solution into a calcium chloride bath, producing calcium alginate fibers. To improve the gelling ability and the absorption capacity of calcium alginate fibers, this study used hydrochloric acid to convert calcium alginate fibers into alginic acid fibers, which was further converted into sodium alginate fibers by treating the fibers with sodium hydroxide in organic solvent. Results showed that alginic acid and sodium alginate fibers and fabrics can be readily made by treating the calcium alginate fibers and fabrics, respectively, with hydrochloric acid and sodium hydroxide. Improved gel blocking properties and absorption capacities were obtained with the sodium alginate fibers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4216–4221, 2006
Synthesis and properties of brominate bismaleimide monomers
Authors: Sava M. 
Published: June 2006

AbstractBrominated bismaleimides were prepared by reacting 3(4)‐maleimidobenzoylchloride with various bisphenols, using chloroform as solvent and triethylamine as acid acceptor. These monomers were characterized by elemental analysis, infrared (IR), and proton nuclear resonance (1H‐NMR) spectroscopy. Thermal properties of monomers were accomplished by differential scanning calorimetry (DSC) and dynamic thermogravimetric analysis (ATG). The properties of these compounds were compared with those of monomers derived from bisphenol A and bisphenol A chlorinated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3881–3885, 2006