bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonisothermal crystallization kinetics and morphology of self‐seeded syndiotactic 1,2‐polybutadiene
Authors: Cai Jiali , Li Tao , Han Ying , Zhuang Yuanqi , Zhang Xuequan 
Published: January 2006

AbstractSubsequent melting behavior after isothermal crystallization at different temperatures from the isotropic melt and nonisothermal crystallization kinetics and morphology of partially melting sPB were carried out by differential scanning calorimetry (DSC), polarized light microscopy (POM), respectively. Triple melting‐endothermic peaks were observed for the polymer first isothermally crystallized at temperatures ranging from 141 to 149°C, respectively, and then followed by cooling at 10°C/min to 70°C. Comparing with the nonisothermal crystallization from the isotropic melt, the nonisothermal crystallization for the partially melting sPB characterized the increased onset crystallization temperature, and the sizes of spherulites became smaller and more uniform. The Tobin, Avrami, Ozawa, and the combination of Avrami and Ozawa equations were applied to describe the kinetics of the nonisothermal process. Both of the Tobin and the Avrami crystallization rate parameters (KT and KA, respectively) were found to increase with increase in the cooling rate. The parameter F(T) for the combination of Avrami and Ozawa equations increases with increasing relative crystallinity. The Ziabicki's kinetic crytallizability index GZ for the partially melting sPB was found to be 3.14. The effective energy barrier Δϵ describing the nonisothermal crystallization of partially melting sPB was evaluated by the differential isoconversional method of Friedman and was found to increase with an increase in the relative crystallinity. At the same time, Hoffman‐Lauritzen parameters (U and Kg) are evaluated and analyzed from the nonisothermal crystallization data by the combination of isoconversional approach and Hoffman‐Lauritzen theory. The Kg value obtained from DSC technique was found to be in good agreement with that obtained from POM technique. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1479–1491, 2006
Pore structure of macroporous monolithic cryogels prepared from poly(vinyl alcohol)
Authors: Plieva Fatima M. , Karlsson Malin , Aguilar Maria‐Rosa , Gomez David , Mikhalovsky Sergey , Galaev Igor Yu. , Mattiasson Bo 
Published: January 2006

AbstractMacroporous monolithic cryogels made from poly(vinyl alcohol) (PVA) with degree of saponification 87.7% have been prepared using a crosslinking reaction with glutaraldehyde under acidic conditions at subzero temperatures. The porous structure of the monolithic cryogels from PVA (cryoPVA), analyzed using optical microscopy, scanning electron microscopy, and environmental scanning electron microscopy, revealed interconnected macropores up to 150 μm in size with a noticeable microporosity of the gel walls. Differential scanning calorimetry measurement showed that more than 90% of the water in the cryoPVA monoliths was freezable water, while the amount of polymer bound water increased with increase in the polymer concentration in the cryoPVA sample. The swelling degree of cryoPVA depended on concentration of polymer in the initial reaction mixture and degree of crosslinking. The cryoPVA monoliths were elastic and spongy‐like materials that can be dried, stored in dried state, and re‐swelled when required. Derivatization of hydroxyl‐groups of the cryoPVA monolith allowed incorporation of required functionality. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1057–1066, 2006
Dyeing properties of Bombyx mori silks grafted with methyl methacrylate and methacrylamide
Authors: Prachayawarakorn Jutarat , Kryratsamee Watthana 
Published: January 2006

AbstractTo improve their dyeing and colorfastness properties, degummed Bombyx mori silks were chemically modified by a grafting technique with either methyl methacrylate (MMA) monomer or methacrylamide (MAA) monomer. Both commercial synthetic dyes, that is, acid and basic dyes, and natural dyes extracted from turmeric, without and with potassium aluminum sulfate mordant, were used in this study. Percentage dye uptake increased with the presence of poly(methyl methacrylate) or polymethacrylamide in the silk fibroin structure regardless of the types of the dyestuffs. Furthermore, compared to the degummed silk, the colorfastness to washing of the MMA‐grafted and MAA‐grafted silks dyed with acid, basic, and curcumin dyestuffs were greatly improved. Colorfastness to both acid and basic perspirations with acid and basic dyestuffs was slightly improved, whereas perspiration fastness remained unchanged for curcumin dyeing without and with the presence of the mordant. Also, the low‐light resistances of the degummed and grafted silks dyed by curcumin dyestuff were notably improved by the MMA and MAA grafting technique. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:1169–1175, 2006
Anionic dye adsorption characteristics of surfactant‐modified coir pith, a ‘waste’ lignocellulosic polymer
Authors: Namasivayam C. , Sureshkumar M. V. 
Published: January 2006

AbstractThe surface of coir pith, an agricultural solid waste, was modified using a cationic surfactant hexadecyltrimethylammonium bromide. Adsorption of anionic dyes on surfactant‐modified coir pith was investigated in a series of batch adsorption experiments. Two anionic dyes, acid brilliant blue (acid dye) and procion orange (reactive dye), were used in the adsorption studies. The effect of process variables such as contact time, concentration of the dyes, adsorbent dose, temperature, and pH were studied in order to understand the kinetic and thermodynamic parameters of the process. The kinetics of adsorption obeyed the second‐order rate equation. The equilibrium adsorption data were fitted into the Langmuir and Freundlich isotherms. It was found that modified coir pith yielded adsorption capacities of 159 and 89 mg/g for acid brilliant blue and procion orange, respectively. Mechanisms involving ion exchange and chemisorption might be responsible for the uptake of dyes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1538–1546, 2006
Chemical modification of nylon 6 and polyester fabrics by ozone‐gas treatment
Authors: Lee Muncheul , Lee Myung Sun , Wakida Tomiji , Tokuyama Takako , Inoue Goichi , Ishida Shinzo , Itazu Toshihiko , Miyaji Yukino 
Published: January 2006

AbstractIn a previous article, we reported on the ozone‐gas treatment of wool and silk fabrics in relation to the gas‐phase processing of textile fabrics. The treatment incorporated an oxygen element into the fiber surface and contributed to an increase in water penetration into the fabric. In this study, nylon 6 and polyester fabrics were treated with ozone gas in the same way as that of the wool and silk fabrics. The treatment incorporated much more oxygen into the fiber surface in the form of COH and COOH, as shown by electron spectroscopy for chemical analysis. Water penetration increased considerably with treatment, and the apparent dyeing rate and equilibrium dye uptake were also improved, especially for the polyester fabric, despite an increase in the crystallinity. Therefore, it seemed that the treatment brought about a change not only in the fiber surface but also in the internal structure of the fibers (the crystalline and amorphous regions) with regard to the dyeing behavior. Further, the mechanical characteristics of the ozone‐gas‐treated polyester and nylon 6 fabrics were measured with a Kawabata evaluation system apparatus. The shearing modulus and hysteresis widths increased with treatment, especially for the polyester fabric. Therefore, it was clear that the treatment caused a change in the fabric hand to crisp. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1344–1348, 2006
Copolymers of styrene with a quaternary europium complex
Authors: Pan Yuanfeng , Zheng Anna , Hu Fuzeng , Xiao Huining 
Published: January 2006

AbstractA complex of Eu3+, benzoate (BA), acrylate (AA), and 1,10‐phenanthroline (Phen) was synthesized in this work. The structure of Eu(BA)2(AA)(Phen) was characterized with elemental analysis, FTIR, and UV spectroscopy. Copolymers containing rare earth complex were prepared via the copolymerization of Eu3+(BA)2(AA)(Phen) with styrene. Semitransparent, luminescent polymer materials with high fluorescent intensity were obtained. The as‐synthesized materials were further characterized by means of IR and UV spectra, which indicated that they were copolymers instead of blends. The fluorescence spectra of the copolymers revealed the intense UV absorption characteristics of the rare earth complex present in the materials, as long as only a small portion of the complex was incorporated into the copolymers. Moreover, thermal analysis showed that the copolymer had excellent heat stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1506–1510, 2006
Grafting of methyl methacrylate onto Antheraea pernyi silk fiber with the assistance of supercritical CO2
Authors: Peng Qi , Xu Qun , Sun Dengfeng , Shao Zhengzhong 
Published: January 2006

AbstractGraft copolymerization of methyl methacrylate (MMA) onto Antheraea pernyi silk fibers, initiated by benzoyl peroxide in the supercritical CO2 was investigated. The grafting degree was determined as a function of impregnating pressure, impregnating time, monomer concentration, initiator concentration, and reaction time. The structural properties of MMA‐grafted fiber were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Grafted MMA was chemically bonded and/or physically adhered to the surfaces of the fibers. The grafted silk fibers exhibited two steps of weight loss according to the characteristic of each component as demonstrated by the thermogravimetric analysis. The water‐retention values indicated that the hydrophobic nature of the fibers was improved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1299–1305, 2006
High modulus polypropylene fibers. II. Influence of fiber preparation upon structure and morphology
Authors: Gregor‐Svetec Diana 
Published: January 2006

AbstractThe influence of drawing on the limiting draw ratio upon formation of the morphological structure of fibers spun from binary polypropylene (PP) blends was studied. Fibers were spun from a fiber‐grade CR‐polymer and from the blends of a fiber‐grade CR‐polymer with a molding‐grade polymer in the composition range of 10–50 wt % added. As‐spun fibers were immediately moderately and additionally highly drawn at the temperature of 145°C. The structure and morphology of these fibers were investigated by small‐angle X‐ray scattering, wide‐angle X‐ray scattering, differential scanning calorimetry, scanning electron microscopy, density, birefringence, and sound velocity measurements. It was shown that continuously moderately drawn fibers are suitable precursors for the production of high tenacity PP fibers of very high modulus, because of so called oriented “smectic” structure present in these fibers. With drawing at elevated temperature, the initial metastable structure of low crystallinity was disrupted and a c‐axis orientation of monoclinic crystalline modification was developed. Hot drawing increased the size of crystallites and crystallinity degree, the orientation of crystalline domains, and average orientation of the macromolecular chains and resulted in extensive fibrillation and void formation. It was found that the blend composition has some influence on the structure of discontinuously highly drawn fibers. With increasing the content of the molding‐grade polymer in the blend, the size of crystalline and amorphous domains, density and crystallinity, as well as amorphous orientation decreased. Relationship has been established between the mechanical properties, crystallinity, and orientation of PP fibers. It was confirmed that by blending the fiber‐grade CR‐polymer by a small percentage of the molding‐grade polymer, maximization of elastic modulus is achieved, mainly because of higher orientation of amorphous domains. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1067–1082, 2006
Controlled heterogeneous modification of cellulose fibers with fatty acids: Effect of reaction conditions on the extent of esterification and fiber properties
Authors: Freire C. S. R. , Silvestre A. J. D. , Neto C. Pascoal , Belgacem M. N. , Gandini A. 
Published: January 2006

AbstractThe controlled heterogeneous partial modification of cellulose fibers with fatty acids, partially preserving the fiber structure, was investigated. The effect of reaction conditions, such as reaction time, fatty acid chain length, and solvent types (swelling and non swelling), on the extent of esterification and fiber properties was evaluated by elemental analysis, IR‐ATR, X‐ray diffraction, 13C CPMAS NMR, contact angle measurement, thermogravimetry, and scanning electron microscopy. The degree of substitution (DS) increased with reaction time and with the swelling effect of the reaction medium and decreased with the fatty acids chain length. Higher the DS, higher is the decrystallization of cellulose as a result of the heterogeneous esterification reaction. The esterification with fatty acids enhanced the hydrophobic character of the fibers, but decreased their thermal stability. These properties are not strongly affected by the DS in the range investigated, viz. up to 1.4. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1093–1102, 2006
Improvement of thermal stability of new heteroaromatic poly(azomethine urethane)s
Authors: Issam A. M. , Ismail J. 
Published: January 2006

AbstractNew poly(azomethine urethane)s were synthesized in the conventional literature manner by reacting a new bisphenol‐containing azomethine group, N,N′‐bis(4‐hydroxyl‐3‐methoxy benzylidine)‐2,6‐diaminopyridine (I) with various diisocyanates, such as hexamethylene diisocyanate (HDI) (a), methylene‐4,4′‐diphenyl diisocyanate (MDI) (b), and toluene‐2,4‐diisocyanate (TDI) (c). The resulting polymers I(a–c) were confirmed by 1H‐NMR, FTIR, UV, and CHN analyses. Thermogravimetric analysis (TGA) revealed that the polymers have high thermal stability. A semicrystalline behavior was noticed for polymers by wide‐angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1198–1204, 2006
Miscibility enhancement on the immiscible poly (vinyl pyrrolidone) and poly (ethyl methacrylate) with poly (vinyl phenol)
Authors: Hsu Wen‐Ping 
Published: January 2006

AbstractThe miscibility behavior of ternary blends of poly (vinyl phenol) (PVPh)/poly (vinyl pyrrolidone) (PVP)/poly (ethyl methacrylate) (PEMA) was investigated mainly with calorimetry. PVPh is miscible with both PVP and PEMA on the basis of the single Tg observed over the entire composition range. FTIR was used to study the hydrogen bonding interaction between the hydroxyl group of PVPh and the carbonyl group of PVP and PEMA at various compositions. Furthermore, the addition of PVPh is able to enhance the miscibility of the immiscible PVP/PEMA and eventually transforms it into a miscible blend, especially when the ratio between PVP/PEMA is 3:1, probably because of favorable physical interaction. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1205–1213, 2006
The effect of substitution levels on the luminescent and degradation properties of fluorescent poly(ester‐anhydride)s
Authors: Fan Jun , Jiang H. L. , Chen Dian , Zhu K. J. 
Published: January 2006

AbstractIn this work, two kinds of diacid monomers were synthesized by a convenient scheme, where 4‐hydroxy‐3‐methoxybenzoic acid (vanillic acid) or 4‐hydroxy‐3,5‐dimethoxybenzoic acid (syringic acid) directly condensated with succinic chloride. Corresponding polyanhydrides were obtained by melt polycondensation. Copolyanhydrides composed of the new monomers and sebacic acid (SA) were further prepared and characterized by NMR, DSC, and fluorometer. The two new kinds of polyanhydride emit strong fluorescence and have similar fluorescent spectra to poly(di(p‐carboxyphenyl) succinate anhydride) (P(dCPS)). The emission wavelength (λem) of the copolymers could be tuned by the excitation wavelength (λex). Degradation rate of the copolyanhydrides decreased as dMOCPS or ddMOCPS fraction increased, and the degradation duration could be modulated from several days to more than 3 months. It addition, the copolyanhydrides displayed typical surface‐degradation characteristics. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1214–1221, 2006
Synthesis and characteristics of poly(methyl methacrylate)/expanded graphite nanocomposites
Authors: Wang Wen‐ping , Liu Yan , Li Xiao‐xuan , You Ye‐zi 
Published: January 2006

AbstractIn this work, we synthesized poly(methyl methacrylate) (PMMA)/expanded graphite (EG) nanocomposites by a new polymerization method. The volume electrical conductivity of the nanocomposite prepared by this way is very high (when the content of EG is about 8 wt %, the conductivity could reach 60 S/cm). The structure of the nanocomposite was investigated by SEM, TEM, IR, and XRD. And we found temperature and voltage were important parameters of governing the electrical conductivity of PMMA/EG nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1427–1431, 2006
The use of 1H NMR and UV–vis measurements for quantitative determination of trans/cis isomerization of a photo‐responsive monomer and its copolymer
Authors: Moniruzzaman M. , Talbot J. D. R. , Sabey C. J. , Fernando G. F. 
Published: January 2006

AbstractPhoto‐induced trans–cis isomerization of trans‐4‐methacryloyloxyazobenzene and its copolymer with methylmethacrylate, synthesized in this work, were investigated in a polar protic (CDCl3) and a polar aprotic (DMSO‐d6) solvent, using 1H‐NMR. The results were cross‐correlated with trans–cis isomerization calculated from UV–visible spectra. The kinetics of the photoisomerization reaction of the monomer species under UV light irradiation is described by a simple first order exchange between the trans and cis forms of the monomer. The behavior was found to be similar for both solvents. The cis‐to‐trans reversion in the absence of irradiation is about 3% of the back reaction under irradiation. For the polymer in solution, the behavior was more complicated and is described by the sum of two equilibria, each of first order exchange kinetics of the trans form with two different types of cis isomer in the polymer; a first type of isomerization similar in behavior to that of the monomer and the second type much faster in cis/trans exchange rate. This bikinetic behavior is in agreement with that of the azobenzene moiety in PMMA as a solid phase mixture. The relative proportion of the two rates comprising the bikinetic effect is solvent‐dependent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1103–1112, 2006
Preparation and solubility of water–methanol mixtures in sulfonated poly(etherketone) containing a cardo‐ring structure
Authors: Akiba Curato , Watanabe Kenji , Nagai Kazukiyo , Hirata Yuichi , Nguyen Quang Trong 
Published: January 2006

AbstractThe preparation and solubility of water–methanol mixtures in sulfonated (1,3‐dihydro‐3‐oxoisobenzofuran‐1,1‐diyl‐1,4‐phenyleneoxy‐1,4‐phenylenecarbonyl‐1,4‐phenyleneoxy‐1,4‐phenylene) (C‐PEK) was systematically studied. The sulfonation was carried out by reacting C‐PEK with 98% sulfuric acid at 60°C. This reaction obeys a first‐order reaction mechanism up to 4 h. The sulfonic acid group was uniformly dispersed in a sulfonated C‐PEK (SC‐PEK) membrane. The introduction of sulfonic acid groups in C‐PEK could increase polymer segmental gaps because of the size of a bulky sulfonic acid group or decrease polymer segmental gaps as a result of polar interactions. The former effect is dominant for SC‐PEK with low sulfonic acid content, whereas the latter occurs for SC‐PEK with high sulfonic acid content. The uptake of pure water or an aqueous methanol solution (e.g., 3, 5, and 10 wt % methanol concentration) in the sulfonated C‐PEK membranes increases with increasing sulfonic acid group content. However, the sulfonated C‐PEK with high sulfonic acid content selectively sorbs water rather than methanol in the membrane. This suggests that the sulfonated C‐PEK membrane could prevent crossover of methanol through the membrane and has potential as a polymer electrolyte for the direct methanol fuel cell. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1113–1123, 2006
Femtosecond‐laser‐assisted wet chemical etching of polymer materials
Authors: Wochnowski C. , Hanada Y. , Cheng Y. , Metev S. , Vollertsen F. , Sugioka K. , Midorikawa K. 
Published: January 2006

AbstractPolymers are modified by femtosecond‐(fs)‐IR‐laser irradiation under various process parameters. Several sorts of thermoplastic polymer are employed: polymethylmethacrylate (PMMA), fluorinated PMMA, poly‐N‐methyl methacrylimide (PMMI), polystyrol, polycarbonate, polyimide, and polyethylene. After the fs‐laser‐induced modification process, the irradiated area is developed by an aqueous solution of a solvent agent (n‐hexane, benzene, and methylisobutylketone). The surface topography of the fs‐laser‐irradiated area is characterized by stylus‐profilometry before and after the development procedure. Some preliminary explanations are given about the solution mechanism of the fs‐laser‐irradiated polymer region. The experimental results are relevant for the fabrication of three‐dimensional (3D)‐structures in the volume of a transparent polymer material by fs‐laser irradiation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1229–1238, 2006
Preparation of poly(lactic acid) fiber by dry‐jet‐wet‐spinning. I. Influence of draw ratio on fiber properties
Authors: Gupta Bhuvanesh , Revagade Nilesh , Anjum Nishat , Atthoff Björn , Hilborn Jöns 
Published: January 2006

AbstractPoly(lactic acid) fiber was prepared by dry‐jet‐wet spinning of the polymer from chloroform solution and with methanol as the precipitating medium. The as‐spun fiber was subsequently made into high strength fiber by two‐step process of drawing at a temperature of 90°C and subsequent heat setting in the temperature range of 120°C. The draw ratio had significant influence on the crystallinity and the tensile strength of the fiber. The fiber with the tenacity of 0.6 GPa and modulus of 8.2 GPa was achieved at a draw ratio of 8. The differential scanning calorimetry revealed an increase in the glass‐transition temperature with the increase in the draw ratio, which suggests the orientation of chains during the drawing process. The surface morphology of the filament as revealed by scanning electron microscopy shows that fibers are porous in nature, but a significant reduction in the porosity and pore size of the fiber was observed with the increase in the draw ratio. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1239–1246, 2006
Hydroxyalkylation of parabanic acid. III. Polymers from parabanic acid and ethylene carbonate
Authors: Zarzyka‐Niemiec Iwona , Naróg Dorota , Lubczak Jacek 
Published: January 2006

AbstractThe influence of initial molar ratio of reagents, amount of catalyst, and temperature of reaction between parabanic acid and ethylene carbonate on structure of product was studied. The reaction led to the opening of the trioxoimidazolidine ring, resulting in formation of thermally resistant linear polymeric products constructed of urea and oxoamidoester subunits linked via imide bond. The percentage of side products was estimated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1443–1449, 2006