bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of fluorinated hydrophobic monomer on the drug release behavior for the thermosensitive hydrogels
Authors: Lee Wen‐Fu , Liu Ta‐Ming 
Published: March 2006

AbstractThree series of copolymeric gels based onN‐isopropylacrylamide (NIPAAm) and perfluoroalkyl methacrylate such as 2,2,3,3,4,4,5,5‐octafluoropentyl methacrylate (OFPMA), 4,4,5,5,6,7,7,7‐octafluoro‐2‐hydroxy‐6‐(trifluoromethyl)heptyl methacrylate (OFHHMA), and 3,3,4,4,5,6,6,6‐octafluoro‐5‐(trifluoromethyl)hexyl methacrylate (OFHMA), were prepared by emulsion polymerization. The effect of perfluoroalkyl methacrylate and sodium lauryl sulfate (SLS), which can act as a surfactant and a pore‐forming agent, on the equilibrium swelling ratio and mechanical properties of the present hydrogels was investigated. Results show that hydrophobic monomers made the swelling ratio of the gel decrease and the mechanical property of the gel increase; however, SLS exhibits a contrary result. In addition, the effect of perfluoroalkyl methacrylate on the drug release behavior was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4661–4667, 2006
Influence of branch content, comonomer type, and crosshead speed on the mechanical properties of metallocene linear low‐density polyethylenes
Authors: Islam Ashraful , Hussein Ibnelwaleed A. 
Published: March 2006

AbstractThe effects of branch content (BC) and comonomer type on the mechanical properties of metallocene linear low‐density polyethylene (m‐LLDPEs) were studied by means of a stress–strain experiment at room temperature. A total of 16 samples with different BCs and comonomer types were used. In addition, the effect of crosshead speed on the mechanical properties of m‐LLDPEs with different BCs was examined. The degree of crystallinity (Xt) of these copolymers was determined by differential scanning calorimetry. In addition, Ziegler–Natta linear low‐density polyethylenes (ZN‐LLDPEs) were also studied for comparison purposes. The increase in BC of m‐LLDPEs decreasedXtand the modulus. However, the ZN‐LLDPEs showed higher small‐strain properties but lower ultimate properties than the m‐LLDPEs with similar weight‐average molecular weights and BCs. In comparison with low‐BC resins, m‐LLDPEs with high BCs exhibited a stronger strain hardening during the stress–strain experiments. Strain hardening was modeled by a modified Avrami equation, and the order of the mechanically induced crystal growth was in the range of 1–2, which suggested athermal nucleation. The crosshead speed was varied in the range 10–500 mm/min. For low‐BC m‐LLDPEs, there existed a narrow crosshead speed window within which the maxima in modulus and ultimate properties were observed. The location of the maxima were independent of BC. The effect of the crosshead speed on the mechanical properties of the m‐LLDPEs was a strong function of BC. However, highly branched m‐LLDPE in this experiment showed a weak dependence on the crosshead speed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 5019–5033, 2006
Development of biodegradable composites with treated and compatibilized lignocellulosic fibers
Authors: Tserki V. , Matzinos P. , Zafeiropoulos N. E. , Panayiotou C. 
Published: March 2006

AbstractThe aliphatic polyester Bionolle 3020 was combined with lignocellulosic fibers, namely, flax, hemp, and wood, to produce biodegradable composite materials. The effect of two fiber surface treatments, acetylation and propionylation, and the addition of maleic anhydride (MA)‐grafted Bionolle 3001 as a compatibilizer on the fiber/matrix interfacial adhesion was studied. The compatibilizer was synthesized through a MA grafting reaction in the presence of dicumyl peroxide as an initiator. The composites' mechanical properties, water absorption, fracture morphology (scanning electron microscopy), and biodegradation were evaluated. Both the fiber treatments and the compatibilizer incorporation significantly improved the composites' tensile strength, whereas an important reduction in the water absorption was found with the addition of treated fibers. Moreover, fiber incorporation into the matrix increased its biodegradation rate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4703–4710, 2006
Enhancement of hydrostatic pressure for water repellent treated fabrics
Authors: Huang Pei‐Yuan , Chao Yu‐Chou , Liao Yih‐Tyan 
Published: March 2006

AbstractThe aqueous dispersions based on perfluorinated acrylate and other comonomers were prepared by means of emulsion polymerization in the presence of stearyl trimethyl ammonium chloride (STAC) and 2,2′‐azobis(2‐amidinopropane) dihydrochloride (ABAP) as water‐soluble initiators. Several different types of resins and additives were added with the water‐repellent polymers. Hydrostatic pressure and water repellency of fabrics that were treated by fluorinated water repellents with different recipes were measured and compared. In addition, the nano clay and the blocked isocyanate crosslinking agent (Jintexguard FCN) do, indeed, substantially increase the hydrostatic pressure. Actually, increased hydrostatic pressure for the water repellent treated fabrics is our objective of this study. However, our recipes containing the fluorinated‐acrylate copolymer, nano clay, and Jintexguard FCN will successfully provide excellent hydrostatic pressure, excellent water repellency, and excellent soft hand. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4711–4715, 2006
Shearing of drag‐reducing polymers with ultrasonic methods in fuel‐oil pipelines: A feasibility study
Authors: Rabecki Frédéric , Henrist Marc , Wildéria Daniel , Cuenca Felix Gómez 
Published: March 2006

AbstractThe purpose of this study was to assess the feasibility and experimental conditions for the shearing of polymers (polyolefins) in fuel oil. These drag‐reducing agents are mixed with fuel oil to reduce the friction during transportation in pipelines and, hence, to save energy, but they must be destroyed after use to restore all the properties of the fuel. One attractive solution consists of the use of ultrasonic energy to carry out this destruction. Ultrasound produces microbubbles (cavitation) in liquids. These bubbles grow and finally collapse, releasing a large amount of energy as a shockwave that can break polymer chains. We studied the influence of parameters affecting cavitation on the shearing index (percentage of initial additive after sonication). We concluded that polymers A and B could be used indiscriminately. The ultrasonic energy could be injected at a frequency of 20 kHz (like in commercial equipment), and the mode of injection did not influence the yield. The results were similar in static and flowing fuels. The temperature did not exert a significant influence. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4723–4728, 2006
Thermoplastic vulcanizates based on epoxidized natural rubber/polypropylene blends: Effect of compatibilizers and reactive blending
Authors: Nakason C. , Wannavilai P. , Kaesaman A. 
Published: March 2006

AbstractEpoxidized natural rubber (ENR) was prepared using the performic epoxidation method. TPVs based on ENR/PP blends were later prepared by melt‐mixing processes via dynamic vulcanization. The effects of blend ratios of ENR/PP, types of compatibilizers, and reactive blending were investigated. Phenolic modified polypropylene (Ph‐PP) and graft copolymer of maleic anhydride on polypropylene molecules (PP‐g‐MA) were prepared and used as blend compatibilizers and reactive blending components of ENR/Ph‐PP and ENR/PP‐g‐MA blends. It was found that the mixing torque, apparent shear stress and apparent shear viscosity increased with increasing levels of ENR. This is attributed to the higher viscosity of the pure ENR than that of the pure PP. Furthermore, there was a higher compatibilizing effect because of the chemical interaction between the polar groups in ENR and PP‐g‐MA or Ph‐PP. Mixing torque, shear flow properties (i.e., shear stress and shear viscosity) and mechanical properties (i.e., tensile strength, elongation at break, and hardness) of the TPVs prepared by reactive blending of ENR/Ph‐PP and ENR/PP‐g‐MA were lower than that of the samples without a compatibilizer. However, the TPVs prepared using Ph‐PP and PP‐g‐MA as compatibilizers exhibited higher values. We observed that the TPVs prepared from ENR/PP with Ph‐PP as a compatibilizer gave the highest rheological and mechanical properties, while the reactive blending of ENR/PP exhibited the lowest values. Trend of the properties corresponds to the morphology of the TPVs. That is, the TPV with Ph‐PP as a blend compatibilizer showed the smallest rubber particles dispersed in the PP matrix, while the reactive blending of ENR/PP‐g‐MA showed the largest particles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4729–4740, 2006
Soybean oil based resin: A new tool for improved immobilization of α‐amylase
Authors: Kahraman M. Vezir , Kayaman‐Apohan Nilhan , Ogan Ays̨e , Güngör Atilla 
Published: March 2006

AbstractAcrylated epoxidized soybean resin has been utilized to immobilize the α‐amylase via UV‐curing technique. Among the numerous methods that exist for enzyme immobilization, entrapment and covalent binding are the focus of this study. The properties of immobilized enzyme were investigated and compared with those of the free enzyme. Upon immobilization by the two methods, the catalytic properties of the enzyme were not considerably changed as compared with that of nonimmobilized form; only the pH profile was broadened for the immobilized enzyme. The free enzyme lost its activity completely in 20 days, where as storage and repeated usage capability experiments demonstrated higher stability for the immobilized form. Immobilized enzyme prepared by attachment method possesses relatively higher activity compared with the activity of those obtained by entrapment method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4757–4761, 2006
Preparation and barrier property of poly(ethylene terephthalate)/clay nanocomposite using clay‐supported catalyst
Authors: Joon Choi Won , Kim Hee‐Joon , Han Yoon Kwan , Hyeong Kwon Oh , Ik Hwang Chang 
Published: March 2006

AbstractPoly(ethylene terephthalate) (PET)/clay nanocomposite was prepared by the direct polymerization with clay‐supported catalyst. The reaction degree of catalyst against the cation exchange capacity of clay was 8 wt %. The intercalation of PET chains into the silicate layers was revealed by X‐ray diffraction studies. SEM morphology of the nanocomposite showed a good dispersion of clay‐supported catalyst, ranging from 30 to 100 nm. The intercalated and exfoliated clay‐supported catalyst in PET matrix was also observed by TEM. The improvement of O2 permeability for PET/clay‐supported catalyst composite films over the pure PET is approximately factors of 11.3–15.6. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4875–4879, 2006
Development of an epoxy system characterized by low water absorption and high thermomechanical performances
Authors: Blanco I. , Cicala G. , Costa M. , Recca A. 
Published: March 2006

AbstractWater absorption and thermomechanical properties of epoxy systems based on multifunctional dicyclopentadiene epoxy novolac resin Tactix556 cured with 4,4′ diaminodiphenilsulfone (4,4′DDS) as curing agent has been studied. The base system was modified by the addition of a novel 40 : 60 PES : PEES (Polyethersulphone : Polyetheretheresulphone) amine‐ended copolymer to improve toughness properties. The effect of thermoplastic addition on water adsorption was studied by gravimetric experiments. The viscoelastic properties of the resulting blend were analyzed by means of dynamic mechanical thermal analysis. The formulated systems were compared with a system based on tetraglycidyl‐4,4′diaminodiphenylmethane resin (MY721) cured with 4,4′ diaminodiphenilsulfone. The use of Tactix556 resin showed that water uptake values were minimized while retaining high glass transition temperatures, and toughness values were found in the same range of standard toughened matrices used for aerospace composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4880–4887, 2006
Effects of the pH, concentration, and solvents on the ultrasonic degradation of poly(vinyl alcohol)
Authors: Vijayalakshmi S. P. , Madras Giridhar 
Published: March 2006

AbstractThe ultrasonic degradation of poly(vinyl alcohol) was investigated at different pHs of the solvent, in different water/solvent binary mixtures, and at different polymer concentrations. The samples were analyzed with gel permeation chromatography. The degradation rate coefficients were determined with a continuous distribution model. A higher degradation rate was obtained at pH extremes, in better solvents, and at lower polymer concentrations. The results are explained and discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4888–4892, 2006
Synthesis, formulation, and characterization of siloxane‐modified epoxy‐based anticorrosive paints
Authors: Ahmad Sharif , Ashraf S. M. , Sharmin Eram , Mohomad Ash , Alam Manawwer 
Published: March 2006

AbstractDiglycidyl ether of bisphenol A epoxy (E) was modified with hydroxyl‐terminated polydimethylsiloxane through a ring‐opening addition polymerization reaction. The structural elucidation of the siloxane‐modified epoxy resin (ES) was carried out with Fourier transform infrared, 1H‐NMR, and 13C‐NMR spectroscopy techniques. The physicochemical characterization of the synthesized resin (ES) was performed with standard methods. E and ES were subjected to paint formulation with the help of a rutile (TiO2) pigment. The formulated paint systems were cured at room temperature with 1,6‐diaminohexane (AH) and 1,3‐diaminopropane (AP), which were used as curatives. The E–AH, E–AP, ES–AH, and ES–AP paint systems were applied to mild steel strips. The physicomechanical and anticorrosive performance of the coated panels was evaluated with standard methods. The thermal analysis of these E–amine and ES–amine systems was carried out via thermogravimetric analysis. The effects of siloxane incorporation and amine curatives on the coating properties of the paint systems were also investigated. The ES–AP system exhibited good thermal and corrosion stability performance among all the E and ES paint systems. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4981–4991, 2006
Micromechanical properties of injection‐molded starch–wood particle composites
Authors: Ueberschaer A. , Cagiao M. E. , Bayer R K. , Henning S. , Calleja F. J. Baltá 
Published: March 2006

AbstractThe micromechanical properties of injection‐molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X‐ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition, creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection‐molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4893–4899, 2006
Wound dressings containing bFGF‐impregnated microspheres: Preparation, characterization, in vitro and in vivo studies
Authors: Huang Sha , Jin Yan , Deng Tianzheng , Wu Hong 
Published: March 2006

AbstractThe purpose of this study was to synthesize a novel wound dressing containing bFGF‐loaded microspheres for promoting healing and tissue regeneration. Gelatin was chosen as the underlying layer and was prepared in porous sponge. As the external layer, elastomeric polyurethane membranes were used. bFGF was loaded in microspheres to achieve prolonged release for higher efficiency. The microspheres were characterized for particle size, in vitro protein release, and bioactivity. The dressings were tested in in vivo experiments on skin defects created on pigs. At certain intervals, wound areas were measured and tissues from wound areas were biopsied for histological examinations. Average size of the microspheres was 14.36 ± 3.56 μm and the network sponges were characterized with an average pore size of 80–160 μm. Both the release efficiency and the protein bioactivity revealed that bFGF was released in a controlled manner and was biologically active, as assessed by its ability to induce the proliferation of fibroblasts. The rate of wound‐area decrease was much faster and the quality of the newly‐formed dermis was almost as good as the normal skin. The application of this novel bilayer wound dressing provided an optimum healing milieu for the proliferating cells and regenerating tissues. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4772–4781, 2006
Crystal structures and their effects on the properties of polyamide 12/clay and polyamide 6–polyamide 66/clay nanocomposites
Authors: Zhang Y. , Yang J. H. , Ellis T. S. , Shi J. 
Published: March 2006

AbstractBoth polyamide 12 (PA 12)/clay and polyamide 6–polyamide 66 copolymer (PA 6/6,6)/clay nanocomposites were prepared by melt intercalation. The incorporation of 4–5 wt % modified clay largely increased the strength, modulus, heat distortion temperature (HDT), and permeation resistance to methanol of the polyamides but decreased the notched impact strength. Incorporation of the clay decreased the melt viscosities of both the PA 12 and PA 6/6,6 nanocomposites. Incorporation of the clay increased the crystallinity of PA 6/6,6 but had little effect on that of PA 12, which explained why the clay obviously increased the glass‐transition temperature of PA 6/6,6 but hardly had any effect on that of PA 12. The dispersion and orientation of both the clay and the polyamide crystals were studied with transmission electron microscopy, scanning electronic microscopy, and X‐ray diffraction. The clay was exfoliated into single layers in the nanocomposites, and the exfoliated clay layers had a preferred orientation parallel to the melt flow direction. Lamellar crystals but not spherulites were initiated on the exfoliated clay surfaces, which were much more compact and orderly than spherulites, and had the same orientation with that of the clay layers. The increase in the mechanical properties, HDT, and permeation resistance was attributed to the orientated exfoliated clay layers and the lamellar crystals. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4782–4794, 2006
Structure and properties of polypropylene alloy in situ blends
Authors: Cui Nannan , Ke Yucai , Lu Zhanxia , Wu Chunhong , Hu Youliang 
Published: March 2006

AbstractA series of polypropylene (PP) alloys containing different ethylene contents have been prepared by the in situ sequential polymerization technique, using Ziegler–Natta catalyst (MgCl2/TiCl4/BMF; BMF is 9,9‐bis(methoxymethyl)fluorine, as an internal donor) without any external donor. The structure and properties of PP alloys obtained have been investigated by nuclear magnetic resonance, Fourier transform infrared spectroscopy, dynamic mechanical analysis, differential scanning calorimetry, and scanning electron microscopy (SEM). The results have suggested that PP alloys are the complex mixtures containing PP, the copolymer with long sequence ethylene chain, ethylene‐propylene rubber (EPR), and block copolymer etc. In the alloys, PP, EPR, and the copolymer with long sequence ethylene chain are partially compatible. The investigation of the mechanical properties indicates that notched Izod impact strength of PP alloy greatly increases at 16°C/−20°C in comparison with that of pure PP. The noticeable plastic deformation is observed in SEM photograph. The increase in the toughness, the mechanical strength of PP alloy decreases to a certain extent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4804–4810, 2006
Comparison of physical and mechanical properties of NR/carbon black/reclaimed rubber blends vulcanized by conventional thermal and microwave irradiation methods
Authors: Sombatsompop N. , Kumnuantip C. 
Published: March 2006

AbstractThis work experimentally monitored the physical and mechanical properties of natural rubber/carbon black/reclaimed rubber blends vulcanized by microwave (MW) irradiation and conventional thermal (CT) systems, and the curing mechanisms are addressed in conjunction with the vulcanizate properties. The microwave oven for rubber blend vulcanization was specially designed and constructed in this work. The results suggested that the tensile modulus and the hardness of the vulcanizates could be enhanced by increasing the reclaimed rubber (RR) content, whereas the tensile stress, elongation at break, and tear strength decreased with the RR loading. The mechanical properties of the vulcanizates from the CT method were higher than those from the MW method. The vulcanizates from the MW method had higher resistance to toluene penetration than those from the CT method. The differences in the properties of the vulcanizates from the CT and MW methods became smaller at higher RR contents. The sensitivity in property changes of the vulcanizates due to addition of the RR content was greater for the CT method than for the MW method. The differences in the results between these two curing systems could be explained in terms of the density and the types of crosslinks present in the vulcanizates. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 5039–5048, 2006
Blends of polypropylene with poly(cis‐butadiene) rubber. III. Study on the phase structure and morphology of incompatible blends of polypropylene with poly(cis‐butadiene) rubber
Authors: Ma Gui‐Qiu , Zhao Yun‐Hui , Yan Li‐Tang , Li Yun‐Yan , Sheng Jing 
Published: March 2006

AbstractScanning electron microscopy (SEM) was used to study the structure and morphology of partly compatible binary blends of polypropylene with poly(cis‐butadiene) rubber. The SEM images were transformed by digital image process software designed by our group, and binarized images were obtained. The size (mean diameters dp and characteristic lengths L) of phases was calculated using binarized images. Small‐angle light scattering was employed to study the structure and morphology of phases in the blends. The structural parameters, including correlation distance ac, average chord lengths l, and mean diameter DS to describe the structure and morphology of phases in binary blends, were calculated based on the corresponding theory. The variation of correlation distance ac, average chord length l, and mean diameter DS were the same as that of mean diameters dp and characteristic length L. At the same time, the distribution of sizes of the dispersed phase in binary blends was calculated with graph transition technique, which possessed log‐normal distribution characterization. The power spectrum images corresponding to small‐angle light scattering images were obtained by two‐dimensional fourier transformation of binary images. The correlation distances acf and average chord length lf have been calculated by intensity of power spectrum images and that was the same as ac and l. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4900–4909, 2006