bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermosetting allyl resins derived from soybean fatty acids
Authors: Luo Qiang , Lui Min , Xu Yijin , Ionescu Mihail , Petrovic Zoran S. 
Published: April 2012

AbstractA novel class of thermosetting resins based on allylated and transesterified epoxidized soybean oil (AE‐ESBO) curable by radical mechanism was developed. The AE‐ESBO was prepared from ESBO by oxirane ring‐opening and then transesterification with allyl alcohol. A family of rubbery to glassy resins was prepared by radical copolymerization of AE‐ESBO with different concentrations of maleic anhydride (MA). Glass transition temperatures (Tg) of these resins ranged from below room temperature to about 130°C based on the amount of MA. In spite of the presence of anhydride groups, water absorption was low <2% even when maleic anhydride was 30% of total weight. Low sol content after extraction and low swelling in toluene indicated high crosslinking density. Tensile moduli of these resins were up to 1.4 GPa and tensile strengths up to 37 MPa. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and characterization of polysaccaride interpolymer complexes: I‐PVA/ι‐carrageenan
Authors: Kantoğlu Ömer , Çaykara Tuncer , Güven Olgun 
Published: April 2012

AbstractThermal and spectroscopic charaterization of PVA, iota carrageenan (IC), and their interpolymer complexes were studied in terms of stability, complex formation, and species determination by XRF, FTIR, Raman, DSC, and TGA. Thermogravimetry analysis showed that initial thermal degradation temperature of PVA/IC decreased from 276 to 256°C with an increase of IC content. The complexation of IC to PVA significantly increased, the thermal stability of IC, where as the thermal stability of PVA increased rather insignificantly. Fourier Transform Infrared (FTIR) and Raman spectroscopic results showed that PVA interacted with IC through OH groups of PVA and IC as shown by the frequency and scattering shift at OH band of FTIR and Raman spectra of each complex. The involvements of ester sulfate and ether groups of IC in interaction were not significant. In the results of the thermal and spectroscopic analysis, 17% content of PVA/IC is the most miscible and intercomplexable weight fraction of PVA/IC. The natural source of IC, which was unknown was characterized by XRF and found to be as potassium salt and Euchema specie of marine red algee of the class Rhodophceae. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Compression molding of biodegradable drug‐eluting implants for sustained release of metronidazole and doxycycline
Authors: Kau Yi‐Chuan , Chen Dave Wei‐Chih , Hsieh Yu‐Te , Lee Fu‐Ying , Liu Shih‐Jung 
Published: April 2012

AbstractThe purpose of this report was to develop solvent‐free biodegradable drug‐eluting implants that provide sustained release of metronidazole and doxycycline. The drug‐eluting implants were prepared using the compression molding technique. To fabricate the implants, polylactide‐polyglycolide copolymers were premixed with metronidazole or doxycycline. The mixture was then compression molded and sintered to form implants of various sizes and geometries. An elution method and an HPLC assay were used to characterize the in vitro release rates of the antibiotics over a 28‐day period. A bacterial inhibition test was also carried out to determine the bioactivity of released antibiotics. The concentrations of both metronidazole and doxycycline were much greater than the minimum inhibitory concentration of Escherichia coli for up to 3 and 4 weeks, respectively, and the bioactivities of the antibiotics remained high after the fabrication process. Furthermore, the initial burst could be minimized and the release rate could be reduced by increasing the size of the implants and by adopting low drug to polymer ratios. By using this compression molding technique and appropriate processing parameters, we will be able to fabricate biodegradable implants of various types of antibacterial drugs for long‐term local deliveries. Eventually, biodegradable drug‐eluting implants may be used to treat various periodontal diseases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Lignocellulosic byproducts as filler in polypropylene: Comprehensive study on the effects of compatibilization and loading
Authors: Fuqua Michael A. , Chevali Venkata S. , Ulven Chad A. 
Published: April 2012

AbstractLignocellulosic byproducts derived from biofuel processes were analyzed as functional fillers in polypropylene‐based biocomposites. Corn cob, a byproduct yielded from corn harvesting for ethanol production, and sunflower hull, a byproduct of seed stripping for biodiesel production, were both examined as ground filler agents. Composite blends with these lignocellulosic fillers at four filler loadings and four variants of surface compatibilizer loading were melt‐compounded using a twin screw extruder and injection molded into test specimens. Tensile testing, notched Izod impact testing, and thermal‐mechanical analysis were performed on the composites. The role of filler type, loading, and surface compatibilization were established and reported. Additionally, elastic modulus and tensile strength were successfully modeled using established particulate composite models. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effects of waste ground fluororubber vulcanizate powders on the properties of silicone rubber/fluororubber blends
Authors: Kim Dae Hyun , Hwang Sung Hyuk , Park Tae Sung , Kim Bong Shik 
Published: April 2012

AbstractWe prepared fluororubber (FKM) vulcanizate powder (FVP) via cryogenic grinding of the FKM commonly used in automobiles and assessed the particle size distribution of the resulting powder. We also prepared silicone rubber (SR)/FKM blends at a ratio of 25/75. Varying amounts of FKM were replaced with equal amounts of FVP within the range of 5–40 wt%, and the physical properties of the resulting SR/FKM/FVP blends were investigated and compared. The TGA curves of the SR/FKM/FVP blends obtained during the thermal property investigations indicated that pyrolysis of SR occurred within two temperature ranges, and that the SR/FKM/FVP blends with 5 wt% FVP demonstrated the highest thermal stability. The storage modulus (E') and loss modulus (E″) of the SR/ FKM/FVP blends increased as the FVP content increased. In the SR/FKM/FVP blends with 5 and 10 wt% FVP, very typical elastic‐deformation behavior was observed. On the contrary, in 40 wt% FVP, the rubber properties disappeared. The mean particle size of FVP was 41.75 μm, and particle size distribution measurements of the SR/FKM/FVP blends suggest particle coexistence such that FVP was condensed and separated. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
In situ formation of biodegradable dextran‐based hydrogel via Michael addition
Authors: Peng Geng , Wang Jing , Yang Fan , Zhang Shuo , Hou Juan , Xing Wanli , Lu Xun , Liu Changsheng 
Published: April 2012

AbstractVinyl‐sulfone‐functionalized dextran (Dex‐VS) was readily prepared by a single‐batch synthetic procedure at room temperature. The thiol molecule, 1,4‐dithioerythritol (DTE, commercially available) with two terminal thiol groups was used as crosslinking agent. Hydrogels were rapidly prepared in situ by Michael addition under mild physiological conditions. Properties including gelation duration, mechanical modulus, and degradation behavior could be expediently controlled. Moreover, the hydrogels had comparatively low cytotoxicity, and the in vivo tests demonstrated an effective delivery of growth factor. This study might provide a powerful material to be used in tissue regeneration. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation of radiation crosslinked foams from low‐density polyethylene/ethylene‐vinyl acetate (LDPE/EVA) copolymer blend with a supercritical carbon dioxide approach
Authors: Wang Bo , Wang Mouhua , Xing Zhe , Zeng Hongyan , Wu Guozhong 
Published: April 2012

AbstractLow‐density polyethylene/ethylene‐vinyl acetate copolymer (LDPE/EVA) blend foams were prepared by a combination of radiation and supercritical carbon dioxide (ScCO2) approach. The radiation effects on LDPE/EVA foams in different ratios were investigated in detail. For the LDPE/EVA blend in a w/w ratio of 70/30, the cell size decreased and the cell density increased with an increase of absorbed dose. The optimal dose and EVA content for the foaming of LDPE/EVA blend in ScCO2 was found to be 50 kGy and 30%, respectively. It was also found that the radiation crosslinked LDPE/EVA blends had a wider foaming temperature range than uncrosslinked samples. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Nitroanilines enhancing the holographic data storage characteristics of the 9,10‐phenanthrenequinone‐doped poly(methyl methacrylate) photopolymer
Authors: Ko Cheng‐Jung , Hsiao Yi‐Nan , Lin Shiuan‐Huei , Chen Po‐Lin , Whang Wha‐Tzong , Hsu Ken Y. , Hsiao Yu‐Sheng , Chen Chun‐Chao 
Published: April 2012

AbstractThis article describes an approach toward improving the characteristics of a photopolymer for holographic data storage application. The maximum diffraction efficiency (ηmax) and dynamic range (M#) of 9,10‐phenanthrenequinone (PQ)‐doped poly(methyl methacrylate; PMMA) both improved significantly after co‐doping with one of three nitroanilines—N,N‐dimethyl‐4‐nitroaniline (DMNA), N‐methyl‐4‐nitroaniline (MNA), and 4‐nitroaniline (pNA). In particular, the value of ηmax increased from 38% for the PMMA/PQ system to 72% for the PMMA/PQ/DMNA system (a 1.89‐fold improvement) and the value of M# increased accordingly from 2.7 to 7.3 (a 2.70‐fold improvement). Thus, the holographic data storage characteristics of PMMA/PQ photopolymers can be improved through co‐doping with nitroaniline compounds. We also investigated the mechanism of the nitroaniline‐induced improvement in optical storage performance using proton nuclear magnetic resonance and X‐ray photoelectron spectroscopy. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Composite materials of graphene nanoplatelets and polypropylene, prepared by in situ polymerization
Authors: Polschikov Sergey V. , Nedorezova Polina M. , Klyamkina Alla N. , Kovalchuk Anton A. , Aladyshev Alexander M. , Shchegolikhin Alexander N. , Shevchenko Vitaliy G. , Muradyan Vyacheslav E. 
Published: April 2012

AbstractNanocomposites of polypropylene and graphene nanoplatelets were synthesized by in situ polymerization in liquid monomer in the presence of highly effective isospecific homogeneous metallocene catalyst. Microstructure, mechanical, dielectric, and thermal properties of composites are presented. X‐ray phase analysis data indicate that graphene nanoplatelets are present in composites as thin flaky particles aggregates, with aspect ratio affected by sonication of reaction mixture. Crystallization temperature of polypropylene increases in composites. Nanocomposites are characterized by high rigidity, thermal stability, and crystallization temperature, low conductivity, and high dielectric losses in the microwave range. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis of cationic polyacrylamide by aqueous two‐phase polymerization in poly(ethylene glycol) chloride solution
Authors: Liu Zaiman , Wei Yaling , Li Baiyu , He Naipu 
Published: April 2012

AbstractAqueous two‐phase copolymerization of acrylamide(AM) and acryloyloxyethyl trimethyl ammonium chloride (DAC) was performed in poly(ethylene glycol) (PEG) solution and in PEG chloride(Cl‐PEG) solution, respectively. Series of cationic polyacrylamide(CPAM) aqueous dispersion were prepared using potassium persulfate (KPS) as initiator. The effect of total amount of monomers, the dosage of initiator, the content of dispersant, the mass ratio of AM to DAC, and the temperature on the conversion, molecular weight, cationic degree, and stability of aqueous dispersion were studied in detail. It is found that the increase of initiator and reaction temperature resulted in the increase of the final conversion, whereas the increase of DAC and PEG concentration resulted in the decrease of the final conversion. The optimum reaction conditions of synthesis were as follows: (1) PEG‐H2O system: PEG 7.5 g, AM 8 g, DAC 2 g, KPS 0.05 g, H2O 100 mL, 70°C. In this process conditions, the molecular weight of CPAM was 3.21 × 106, the cationic degree of CPAM was 24.4%, the storage stability of the aqueous dispersion was over 3 months. (2) Cl‐PEG‐H2O system: Cl‐PEG 7.5 g, AM 8 g, DAC 2 g, KPS 0.05 g, H2O 100 mL, 65°C. In this process conditions, the molecular weight was 3.68 × 106, the cationic degree was 23.3%, and the storage stability of the aqueous dispersion was over 6 months. In general, the stability of CPAM aqueous dispersion in Cl‐PEG system is much better than in PEG system. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Electrosynthesis and characterizations of a multielectrochromic copolymer based on pyrrole and 3,4‐ethylenedioxythiophene
Authors: Yi‐Jie Tao , Hai‐Feng Cheng , Wen‐Wei Zheng , Zhao‐Yang Zhang 
Published: April 2012

AbstractA copolymer based on pyrrole and 3,4‐ethylenedioxythiophene (EDOT) was electrochemically synthesized on an indium tin oxide ITO/glass electrode in acetonitrile containing lithium perchlorate (LiClO4). The resultant copolymer is characterized via cyclic voltammetry, FTIR, SEM, XPS, and spectroelectrochemical analysis. The spectroelectrochemical analysis revealed the copolymer film has distinct electrochromic properties with respect to the homopolymers, and presented four colors (amaranth, brick red, dark grey, and light blue) under various applied potentials. For the copolymer in the neutral state, the calculated onset energy for the π–π* transition (Eg) is 1.69 eV, and the absorption peak (λmax) is located at 508 nm. The maximum transmittance contrast (ΔT%) is 39.2% at 946 nm between the fully oxidized and intermediate(−0.4 V) states. Successive cyclic voltammograms and electrochromic switching experiment indicate the good stability of the copolymer because of the incorporation of EDOT units into the polypyrrole. It retains 81% of the original electroactivity and 71.8% of contrast after 2000 cycles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Morphology and properties of polystyrene/agave fiber composites and foams
Authors: Moscoso Francisco Javier , Martínez Liliana , Canche Gonzalo , Rodrigue Denis , González‐Núñez Rubén 
Published: April 2012

AbstractIn this work, agave fibers were blended with polystyrene to produce foamed and unfoamed composites. The effect of fiber size and density reduction on the morphological, thermal, mechanical, and rheological properties, as well as crystallinity and water absorption kinetics of the composites was assessed. The results show that Young's modulus and tensile strength increased with increasing fiber content, but decreased with density reduction. Increasing fiber content and decreasing the size of the fibers both increased crystallinity of the composites. Finally, water uptake and diffusion coefficient were found to increase with increasing fiber content for all sizes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Crosslinkable fluorinated hyperbranched polyimide for thermo‐optic switches with high thermal stability
Authors: Cao Zijian , Jin Lin , Liu Yu , Jiang Zhenhua , Zhang Daming 
Published: April 2012

AbstractA series of fluorinated hyperbranched polyimides (FHBPIs) were synthesized by condensation of a triamine monomer, 1,3,5‐tris(2‐trifluoromethyl‐4‐minopheoxy) benzene (TFAPOB) and various aromatic dianhydride monomers with different linear length for application on integrated optical devices. Near infrared absorption measurement shows that it has high transparency in optical communication wavelength region. The glass transition temperature and thermal decomposition temperature were 189°C and 596°C, respectively. According to the atomic force microscopy analysis, the surface roughness of the FHBPI films is 0.208 nm. A classic Mach–Zehnder interferometer thermo‐optic switch with single mode waveguide fabricated by FHBPIs represents excellent switching characteristic. The rise time and fall time of this device are 530 µs for both. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Segmental mobility in the vicinity of Tg in PS/SBR blends: Nanodomain size prediction of the dispersed phase
Authors: Yousefi Ali Akbar 
Published: April 2012

AbstractThe blends of polystyrene (PS) and styrene‐butadiene rubber (SBR) are melt‐blended at different ratios to form physical thermoplastic elastomers. This polymeric blend is expected to behave more or less similar to chemically synthesized block copolymers such as styrene‐butadiene block copolymers (SBS). In this study, mechanical and the thermomechanical properties of this blend are investigated and compared to those of SBS copolymer. As far as morphology is considered, the blend shows a two‐phase morphology with an interface, which shows very weak interactions. According to the observed morphology and the domain size of dispersed phase the blends are of good integrity. The mechanical properties of the blends confirm the integrity of the blend and effective interface stress transfer. The tensile and Izod impact properties of the blends shows improvements upon increase in SBR content of the blend. As SBR content augments the elongation at break increases, whereas tensile dissipated energy and impact resistance go through a maximum. Therefore, blend with SBR‐content in 60–75% range can be considered as preferred one. In a wide range of concentration a phase inversion was observed and Tg‐depression was detected also for the SBR phase. This Tg‐depression was correlated to the changes in dynamics of segments (segmental mobility) near the surfaces. Using the proposed relationships between Tg‐depression and the thickness of the thin films, it was tried to calculate domain size of SBR inclusions in PS matrix. A rough correlation between SBR domain sizes in SEM images and calculated thicknesses using Tg‐depression in thin films was found. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Fluorinated waterborne shape memory polyurethane urea for potential medical implant application
Authors: Wang Zi , Hou Zhongyu , Wang Yanfang 
Published: April 2012

AbstractA series of crosslinked fluorinated waterborne shape memory polyurethane urea (PUU) ionomers were synthesized from polycaprolactone diol, perfluoropolyether (PFPE) diol, dimethylolproionic acid, isophorone diisocyanate, ethylenediamine (EDA), and diethylenetriamine (DETA). The effect of PFPE content in the soft segment and the degree of crosslinking on the molecular structure and the properties of these PUU films was examined and studied. Differential scanning calorimetry showed that the transition temperature for these Tm type shape memory PUU could be fine tuned by PFPE weight percentage and EDA/DETA ratio in the range between 33 and 44°C, covering the range of body temperature. Although incorporating amorphous fluorinated units into semicrystalline soft segment compromised the shape memory performance of PUU with linear structure as expected, the introduction of crosslinking structure using DETA as a trifunctional chain extender could still retain quite high strain recovery rate (above 90%) at 100% stretching deformation. Furthermore, the relationship of these properties as well as thermal stability with hydrogen bonding was also discussed by evaluation of the carbonyl stretching region in Fourier transform infrared spectra. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The Microvascular Anatomy of the Trachea in Adult Xenopus laevis Daudin (Lissamphibia; Anura): Scanning Electron Microscopy of Vascular Corrosion Casts and Correlative Light Microscopy
Authors: Tangphokhanon Wasan , Lametschwandtner Alois 
Published: April 2012

AbstractStudies on the amphibian respiratory tract microvascular anatomy are few and contradictory. Using scanning electron microscopy of vascular corrosion casts, correlative light microscopy of paraplast‐embedded Goldner‐stained serial tissue sections, and three‐dimensional morphometry, we studied the topographic microvascular anatomy in the trachea of the adult South African Clawed Toad, Xenopus laevis Daudin. Histomorphology showed that the cartilaginous portion of the trachea contained irregularly shaped hyaline cartilage plates in its cranial and caudal portions and C‐shaped hyaline cartilage rings in the middle portion. Tracheal cartilages formed large continuous plates on the ventral circumference, numerous small discontinuous plates on the dorsal circumference, and large vertical plates on the caudolateral circumference. The muscular portion of the trachea consisted of bands of smooth muscle that joined the free ends of cartilage plates. The supply of the trachea was via pulmonal artery—tracheobronchial trunk artery—tracheobronchial artery—tracheal artery. The subepithelial capillary network consisted of rectangular meshes which are in the area of the tracheal cartilages located between the cartilages and the respiratory epithelium. Small tracheal veins merged into a single tracheal vein that emptied into the pulmonary vein. Because of its dense subepithelial capillary network and its drainage into the pulmonal vein, the trachea could actively take part in respiration. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Promotion of bone repair by implantation of cryopreserved bone marrow–derived mononuclear cells in a rabbit model of steroid‐associated osteonecrosis
Authors: Xie Xin‐Hui , Wang Xin‐Luan , He Yi‐Xin , Liu Zhong , Sheng Hui , Zhang Ge , Qin Ling 
Published: April 2012

AbstractObjectiveCytotherapy is an insufficient method for promoting bone repair in steroid‐associated osteonecrosis (SAON), and this has been attributed to impairment of the bioactivity of bone marrow–derived stem cells (BMSCs) after pulsed administration of steroids. Cryopreserved autologous bone marrow–derived mononuclear cells (BMMNCs), which contain BMSCs, might maintain their bioactivity in vitro. This study sought to investigate the effects of cryopreserved BMMNCs, before steroid administration, on the enhancement of bone repair in an established rabbit model of SAON.MethodsFor in vitro study, bone marrow was harvested 4 weeks before SAON induction from the iliac crests of rabbits (n = 10) to isolate fresh BMMNCs, and the BMMNCs were then cryopreserved for 8 weeks. Both the fresh and the cryopreserved BMMNCs were evaluated for their bioactivity and osteogenic differentiation capacity. In addition, BMMNCs were isolated 2 weeks after SAON induction and subjected to the same evaluations. For in vivo study, cryopreserved BMMNCs were implanted into the bone tunnel during core decompression of the femur (n = 12 rabbits) after the induction of SAON, and tissue regeneration was evaluated by micro–computed tomography and histologic analyses at 12 weeks postoperation.ResultsIn vitro, there were no significant differences in the bioactivity or ability to undergo osteogenic differentiation between fresh BMMNCs and cryopreserved BMMNCs, but after SAON induction, both features were decreased significantly. In vivo, the bone mineral density, ratio of bone volume to total volume of bone, and volume and diameter of neovascularization within the bone tunnel were significantly higher in the BMMNC‐treated group compared to the nontreated control group at 12 weeks postoperation.ConclusionCryopreserved BMMNCs maintained their bioactivity and promoted bone regeneration and neovascularization within the bone tunnel after core decompression in this rabbit model of SAON.