bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous interpenetrating polymer networks based on bromoacrylated castor oil polyurethane
Authors: Eren Tarik , Çolak Semra , Küsefoglu Selim H. 
Published: February 2006

AbstractIn the first part of this study, simultaneous addition of bromine and acrylate to the double bonds of castor oil was achieved. In the second part of the study, bromoacrylated castor oil (BACO) was reacted with toluenediisocyanate (TDI), to form a prepolyurethane (BACOP). The prepolyurethanes were reacted with styrene (STY), 2‐hydroxyethyl methacrylate (HEMA), methyl methacrylate (MMA), and 3‐(acryloxy)‐2‐hydroxy propyl methacrylate (AHPMA) free radically, using the acrylate functional group to prepare the simultaneous interpenetrating polymer networks (SINs). 2,2′‐Azobis (isobutyronitrile) (AIBN) was used as the initiator and diethylene glycol dimethacrylate (DEGDMA) was used as the crosslinker. BACO and BACOP were characterized by IR, 1H‐NMR, and 13C‐NMR techniques. Synthesized polymers were characterized by their resistance to chemical reagents, thermogravimetric analysis, and dynamic mechanical thermal analyzer (DMTA). All the polymers decomposed with 6–10% weight loss in a temperature range of 25–240°C. MMA‐type SIN showed the highest Tg (126°C), while STY‐type SINs showed the highest storage modulus (8.6 × 109 Pa) at room temperature, with respect to other synthesized SINs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2947–2955, 2006
The physical properties of aqueous cationic–nonionic polyurethane with poly(ethylene glycol methyl ether) side chain and its blend with aqueous cationic polyurethane
Authors: Yen Meng‐Shung , Tsai Hsiang‐Chin , Hong Po‐Da 
Published: February 2006

AbstractThe cationic–nonionic dispersing centers with different chain lengths of poly ethylene glycol methyl ether (N‐PDEA 750, N‐PDEA 2000) were prepared from N‐diethanol amine (NDEA), isophorone diisocyanate (IPDI), and poly(ethylene glycol methyl ether) (PEO Mw = 750 and 2000), whereas aqueous cationic–nonionic polyurethane (N‐PDEA PU) with different side chain lengths were prepared by N‐PDEA 750 (or N‐PDEA 2000), 4,4‐methylene bis(isocyantocyclohexane) (H12MDI), polytetramethylene glycol (PTMG 2000), ethylene diamine (EDA), and glycolic acid (GA) as cationic–nonionic dispersing center, hard segment, soft segment, chain extender, and quarternizing agent, respectively. The thermal and mechanical properties of PU casting film were then discussed. We also used N‐methyldiethyolamine (N‐MDEA) without PEO as cationic dispersing center to synthesize aqueous cationic PU (N‐MDEA PU). The PU blends were blending N‐PDEA 750 PU and N‐MDEA PU by different weight ratios and the physical properties of casting films and coated fabric of PU and PU blends were investigated. Regarding the thermal properties, we have found out that the cationic–nonionic PU (N‐PDEA 750 PU, N‐PDEA 2000 PU) has lower Tgs, Tms, TmH, and ΔHH than N‐MDEA PU, apart from ΔHs. The N‐PDEA 2000 PU with longer side‐chain PEO has lower Tgs, higher Tms and ΔHs than N‐PDEA 750 PU. As for mechanical property, N‐PDEA PU has lower tensile strength of casting film compared with N‐MDEA PU. Regarding the comparison of side chain length of PEO, N‐PDEA 2000 PU with longer side chain has higher tensile strength than N‐PDEA 750 PU with shorter side chain length. In addition, N‐PDEA 2000 PU group that shows hard property in stress–strain curve, whereas N‐PDEA 750 PU shows soft property. The tensile strength of PU blends decreases as the content of N‐PDEA 750 PU increases. When the low‐blend ratio of N‐PDEA 750 PU (e.g., 5%), the tensile strength of casting film only shows less influence that can improve the elongation effectively. In terms of coating‐treated fabrics, cationic–nonionic PU‐coated fabrics show lower waterproof capacity (WP) than those treated by cationic PU. However, the water vapor permeability (WVP) and antiyellowing of the N‐PDEA 750 PU coated fabrics are significantly better than the one treated by cationic polyurethane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2963–2974, 2006
Flow through diffusion cell method: A novel approach to study in vitro enzymatic degradation of a starch‐based ternary semi‐interpenetrating network for gastrointestinal drug delivery
Authors: Bajpai S. K. , Saxena Sutanjay 
Published: February 2006

AbstractA ter‐polymeric semi‐IPN has been synthesized by aqueous polymerization of methacrylamide in the presence of polyethylene glycol (PEG) and natural polysaccharides starch, and its enzymatic degradation has been studied in the phosphate buffer medium of pH 6.8 at the physiological temperature 37°C. With the increase in content of enzyme in the external solution and starch in the hydrogel, the degradation is enhanced while the extent of degradation is lowered with the increase in the amount of PEG in the hydrogel. The initial water content also affects the degradability of the polymer matrix. The degradation follows Michaelis–Menten kinetics and KM was found to be 3.92 × 10−5 mol dm−3. The hydrogel exhibits different degradation behavior when studied by “traditional degradation method” (TDM) and “flow through diffusion cell” (FTDC) method. The degradability is suppressed in FTDC method because of the absorption of amylase molecules onto filler particles. Finally the nature and size of the filler particles also affects the degradation behavior of hydrogels. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2975–2984, 2006
Synthesis and characterization of biodegradable polyethylene by graft copolymerization of starch using glucose–Ce(IV) redox system
Authors: Maharana T. , Singh B. C. 
Published: February 2006

AbstractGraft copolymerization of low‐density polyethylene (LDPE) onto starch was carried out with glucose–cerium(IV) redox initiator in an aqueous sulfuric acid medium under nitrogen atmosphere. The graft yield was influenced by various parameters like reaction time, temperature, and concentrations of acid, glucose, polyethylene (PE), starch, and initiator. A maximum graft yield of 85.66% was obtained at a temperature of 50°C and at higher concentration of starch. Effect of grafting on crystallinity, morphology, and thermal properties of modified PE has been evaluated using X‐ray diffraction, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA/DTA). Biodegradability of starch‐grafted PE has been tested applying soil‐burial test. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3229–3239, 2006
Effect of weathering cycle and manufacturing method on performance of wood flour and high‐density polyethylene composites
Authors: Stark Nicole M. 
Published: February 2006

AbstractWood–plastic lumber is promoted as a low‐maintenance high‐durability product. When exposed to accelerated weathering, however, wood–plastic composites may experience a color change and loss in mechanical properties. Differences in weathering cycle and composite surface characteristics can affect the rate and amount of change caused by weathering. In this study, 50% wood flour filled high‐density polyethylene composite samples were injection molded, extruded, or extruded and then planed to remove the manufacturing surface characteristics. Composites were exposed to two accelerated weathering cycles in a xenon arc weathering apparatus. This apparatus exposed the samples to xenon arc radiation, which is a combination of UV, visible, and IR radiation that is similar to solar radiation. Composites were exposed to radiation with or without water spray. After exposure to radiation and water spray, composites with more wood component at the surface (i.e., planed samples) experienced a larger percentage of total loss in flexural modulus of elasticity and strength after weathering compared with the other composites. Composites exposed to radiation only did not experience as much change in properties as those exposed to radiation with water spray. The results of this study demonstrate that exposing wood–plastic composites to water spray in combination with radiation is more severe than exposing wood–plastic composites to radiation only. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3131–3140, 2006
Linear viscoelastic properties of HFPE‐II‐52 polyimide
Authors: Antonakakis J. N. , Bhargava P. , Chuang K. C. , Zehnder A. T. 
Published: February 2006

AbstractThe polyimide HFPE‐II‐52 was developed at NASA Glenn Research Center for use as a matrix in high temperature composite materials. The unique properties of such composites stem largely from the performance of the matrix at high temperature. Thus, as part of a larger effort to study high temperature composite materials, the linear viscoelastic properties of HFPE are measured and a mathematical model of the properties is developed. In particular, storage, loss, and stress relaxation moduli were obtained from cyclic and transient loading experiments. A Prony series was fit to the relaxation modulus data. As a cross check, the fit to the relaxation modulus was converted to storage and loss moduli and compared with those measured directly. Effects of postcuring and of moisture on the properties are investigated as well. These results provide researchers with a constitutive model for HFPE‐II‐52 and provide some insight into the performance of HFPE matrix composites at high temperatures. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3255–3263, 2006
Determination of impurities in industrial caprolactam produced from toluene by SPME and GC–MS
Authors: Li Na , Zou Jiankai 
Published: February 2006

AbstractSolid‐phase microextraction (SPME) in combination with gas chromatography‐mass spectrometry (GC–MS) was applied to study the impurities in industrial caprolactam produced from toluene. Various nitriles, lactones, amides, and alcohols were detected to be the main impurities in caprolactam products. Trace amounts of heterocyclic compounds, which had great effects on the quality of caprolactam, were also successfully detected. Those were pyrrole, 2‐ethyl‐3‐methyl pyrazine, 5,6,7,8‐tetrahydroquinoxaline, quinoxaline, 2,3‐dimethyl quinoxaline, 2‐pyridinamide, etc. The effects of some impurities on caprolactam quality and the polymerization of caprolactam as well as the possible origin of the main impurities were also discussed. This could be of great importance to the industrial purity control of caprolactam. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3141–3144, 2006
Acetylation of cellulose using recyclable polymeric catalysts
Authors: Luo Jie , Sun Yuyu 
Published: February 2006

AbstractThe esterification of cellulose with acetyl chloride in N‐methyl‐2‐pyrrolidinone proceeded smoothly using crosslinked polyvinylpyridine (C‐PVP) as catalysts. The structures of the cellulose acetates were confirmed by FTIR, 1H‐NMR, and 13C‐NMR analyses. The molecular weights were determined by GPC, and the thermal properties were characterized with DSC and TGA. The effects of reaction conditions on yields and degree of substitutions were evaluated in detail. C‐PVP was recycled by a simple alkali treatment, and the recycled C‐PVP could be readily reused as catalysts in cellulose acetylations without adverse effects on the reactions. The influences of C‐PVP on the structures of cellulose acetate samples were further discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3288–3296, 2006
Effect of porosigen and hydrophobic monomer on the fast swelling–deswelling behaviors for the porous thermoreversible copolymeric hydrogels
Authors: Lee Wen‐Fu , Yeh Yu‐Chen 
Published: February 2006

AbstractA series of porous thermoreversible copolymeric hydrogels were prepared from N‐isopropylacrylamide (NIPAAm) and hydrophobic monomers such as 2,2,3,3,4,4,5,5‐octafluoropentyl methacrylate (OFPMA) and n‐butyl methacrylate (BMA) and CaCO3 or poly(ethylene glycol) 8000 (PEG8000) as porosigen by emulsion polymerization. The effect of hydrophobic monomers and porosigens on the fundamental properties, such as equilibrium swelling ratio, swelling kinetics, gel strength, crosslinked densities, etc., and fast swelling–deswelling behavior for the present copolymeric hydrogels were investigated. Results showed that the deswelling rates for the gels porosigened by CaCO3 were more rapid than those gels foamed by PEG8000. Results also showed that the swelling rates for the gel foamed by CaCO3 were higher than those for the gel foamed by PEG8000. At the same time, results also showed that the gels with OFPMA foamed by CaCO3 exhibit a faster swelling–deswelling behavior than those gels with BMA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3152–3160, 2006
Calorimetric study of the system clorhydrate of chitosan/glutaraldehyde(1,5‐pentanedial)
Authors: Fraga F. , Blanco J. , Luzardo A. , Leira L. , Rodríguez‐Núñez E. , Martínez‐Ageitos J. M. , Castro‐Díaz C. 
Published: February 2006

AbstractThe reaction of glutaraldehyde with primary amino groups of chitosan produces covalent crosslinking in a matricial microsphere formulation. The influence of the crosslinking times on the calorimetric parameters (glass transition temperatures, enthalpy, and endothermic peak) of the system clorhydrate of chitosan/glutaraldehyde (1,5‐pentanedial) was studied using differential scanning calorimetry in dynamic mode. Using Kissinger′s method, the activation energies for the water remaining process were obtained without a precise knowledge of the reaction mechanism from the experimental endothermic peaks. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3297–3301, 2006
Dyeing properties of PECH‐amine cationized cotton with acid dyes
Authors: Rong Li , Feng Gu 
Published: February 2006

AbstractThe dyeing properties of cationic cotton dyed with acid dyes are examined in this study. For comparison, nylon 6 and untreated cotton are dyed by the same acid dyes (Sandolan Red MF‐2BL, Sandolan Golden Yellow MF‐GL, and Sandolan Blue MF‐GL). A cationic agent, polyepichlorohydrin‐dimethylamine (PECH‐amine), is used to modify cotton fabric. Significant increase in color yield is observed for cationic cotton over untreated cotton because of the introduced positively charged sites by cationic modification. Deeper shades are obtained in all cases with cationic cotton. All of the acid dyes used in this study show significant hooking behavior with both cationic cotton and nylon. © 2006 Wiley Periodicals, Inc. J Appl Polym Polym Sci 100: 3302–3306, 2006
Damping properties of chlorinated polyethylene‐based hybrids: Effect of organic additives
Authors: Zhang Cheng , Wang Ping , Ma Chun‐an , Sumita Masao 
Published: February 2006

AbstractIn this article, the damping properties of organic hybrids consisting of chlorinated polyethylene (CPE), N,N‐dicyclohexyl‐2‐benzothia‐zolylsufenamide (DZ), and 4,4′‐thio‐bis(3‐methyl‐6‐tert‐butylphenol) (BPSR) have been investigated by dynamic mechanical analysis (DMA). It is found that DZ and BPSR seem to have a synergistic effect on the damping improvement of CPE/DZ/BPSR hybrids. For CPE/DZ/BPSR three‐component hybrids, when BPSR content is below 20 wt %, the values of damping peak maximum are just the same, while the damping peak position shifts to a higher temperature at a higher BPSR concentration. When BPSR content is fixed at 10 wt %, the damping peak maximum increases with increasing DZ/CPE ratio, while there is little shift in the peak position within the ratio range of 0.75–1.25. The decrease in damping peak maximum against annealing can be attributed to the phase separation resulting from the crystallization of hybrids components. Such a crystalline phase, which has been formed during annealing, contains not only pure DZ crystallites but also some CPE–DZ or CPE–DZ–BPSR eutectic crystals. Furthermore, the damping stability of the hybrids can be improved excellently by adding a small amount of BPSR or changing hot‐pressing temperature. These may imply that a series of high‐performance damping materials possessing both high damping peak maximum and controllable damping peak position can be achieved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3307–3311, 2006
Synthesis of new anionic HTPB‐based polyurethane elastomers: Aqueous dispersion and physical properties
Authors: Poussard Loïc , Burel Fabrice , Couvercelle Jean‐Pierre , Loutelier‐Bourhis Corinne , Bunel Claude 
Published: February 2006

AbstractNew segmented polyurethane (PU) anionomers based on hydroxytelechelic polybutadiene (HTPB) were synthesized via an environment‐friendly chemical route. Incorporation of carboxylated functions on the PU soft segment was carried out using a thiol‐ene reaction on HTPB vinyl double bonds with thioglycolic acid. PU water dispersions were obtained by addition of a water dispersible polyisocyanate, i.e., Bayhydur® 3100, to the modified ionic HTPB water dispersions. The key factor of this formulation is the control of ionic concentration apart from the hard segment content, oppositely to all other PU anionomer formulations. The influence of ionic content was studied through all steps of the PU material synthesis, from aqueous dispersions upto crosslinked materials' physical properties. For fully neutralized precursors, the stability of the ionic aqueous dispersions was higher than that was in six months. In all cases, particles were smaller than 200 nm. PU glass transition temperature, surface hydrophily and swelling increased with ionic content. But, however, PUs exhibit hydrophobic surface properties with a maximum surface tension of 45 mN m−1 and a limited water uptake. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3312–3322, 2006
Effects of spinning conditions on structure and properties of multifunctional fibers of polyimidoamide nanocomposites
Authors: Mikołajczyk Teresa , Olejnik Magdalena 
Published: February 2006

AbstractThe effects of basic fiber‐forming parameters on the porous structure, moisture absorption, and strength properties of fibers from polyimidoamide nanocomposites were examined. Beneficial fiber‐forming conditions were established in consideration of the fiber sorption and strength properties. It was found that the incorporation of montmorillonite into the fiber‐forming polymer resulted in beneficial increases in fiber porosity and internal surface area. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3323–3331, 2006
Aging and moisture effects on the tensile properties of starch/poly(hydroxyester ether) composites
Authors: Lawton J. W. , Doane W. M. , Willett J. L. 
Published: February 2006

AbstractThe effects of starch and aging on the mechanical properties of starch/poly(hydroxyester ether) (PHEE) composite materials were characterized. Native or modified cornstarches were extruded with PHEE. Composites were aged for up to 20 months at either 23°C and 50% relative humidity (RH) or over calcium sulfate to keep the composites dry. The tensile strength (TS) of the composites was affected by the type of starch filler that they contained. Composites containing native or crosslinked starch had significantly greater TS than composites containing octenylsuccinated starch. It was thought that the octenylsuccinate modification of the starch granule affected the adhesion between the starch and PHEE. Aging the composites at 50% RH had a significant effect on the mechanical properties of the composites, with TS and Young's modulus (YM) significantly decreasing and the elongation to break significantly increasing after 20 months of storage. Composites stored at 50% RH absorbed water, which caused changes in the mechanical properties by plasticizing PHEE. Composites containing poly(lactic acid) and PHEE did not experience large reduction in TS and YM when aged at 50% RH, even though they also absorbed water. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3332–3339, 2006
Reactive blending of modified polypropylene and polyamide 12: Effects of compatibilizer content on crystallization and blend morphology
Authors: Wu Yang , Yang Yuming , Li Binyao , Han Yanchun 
Published: February 2006

AbstractThe crystallization behavior and morphology of nonreactive and reactive melt‐mixed blends of polypropylene (PP) and polyamide (PA12; as the dispersed phase) were investigated. It was found that the crystallization behavior and the size of the PA12 particles were dependent on the content of the compatibilizer (maleic anhydride–modified polypropylene) because an in situ reaction occurred between the maleic anhydride groups of the compatibilizer and the amide end groups of PA12. When the amount of compatibilizer was more than 4%, the PA12 did not crystallize at temperatures typical for bulk crystallization. These finely dispersed PA12 particles crystallized coincidently with the PP phase. The changes in domain size with compatibilizer content were consistent with Wu's theory. These investigations showed that crystallization of the dispersed phase could not be explained solely by the size of the dispersion. The interfacial tension between the polymeric components in the blends may yield information on the fractionation of crystallization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3187–3192, 2006
Relationship between the thermal degradation chemistry and flammability of commercial flexible polyurethane foams
Authors: Denecker C. , Liggat J. J. , Snape C. E. 
Published: February 2006

AbstractIn this article, we report the use of a variety of analytical methods, in particular, solid‐state 1H‐NMR and 13C‐NMR to characterize the relationship between the condensed‐phase chemistry and burning behavior as determined by a series of combustion tests for two commercially derived flexible polyurethane foams, one combustion‐modified. The combustion tests showed that the foams met several regulatory requirements in terms of their fire performance, whether or not they were combustion‐modified. Both foams passed the MV SS 302 and CAL 117 small‐flame tests. The nonmodified foam failed the Crib 5 test, but this test had a much larger ignition source. The particular problem with the nonmodified foam was melt drip into the flame zone. This led to a steady maintenance of the fuel feed and a rapid escalation of the fire. In contrast, the combustion‐modified foam showed little melt drip and self‐extinguished. Thermal analysis data for the two foams showed that melamine acted in part as an endothermic heat sink. This alone did not account for the much reduced melt flow and drip of the combustion‐modified foam, but the solid‐state 1H‐NMR data clearly showed that the molecular mobility of the combustion char from combustion‐modified foam was lower than the unmodified foam char, which indicated that the flame‐retardant formulation in the combustion‐modified foam acted by a condensed‐phase mechanism. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3024–3033, 2006
Effect of exfoliation and dispersion on the yield behavior of melt‐compounded polyethylene–montmorillonite nanocomposites
Authors: Truss Rowan W. , Yeow Tay Kiah 
Published: February 2006

AbstractThe yield behavior of melt‐mixed nanocomposites containing 5 wt % organically modified montmorillonite in matrices of a linear low‐density polyethylene (LLDPE) or a modified polyethylene was studied as a function of the temperature and strain rate. In the melt‐mixed LLDPE nanocomposite, the montmorillonite showed a slight increase in the clay spacing, which suggested that the clay was at best intercalated. Transmission electron microscopy (TEM) images showed that the dispersion in this nanocomposite was poor. The use of the modified polyethylene promoted exfoliation of the clay tactoids in the nanocomposite, as assessed by X‐ray diffraction and TEM. In both nanocomposites, the yield mechanisms were insensitive to the addition of the organoclay, even though modest increases in the modulus were produced. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3044–3049, 2006