bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of the oxygen‐limiting amount consumed by polymeric melt in the thermooxidative degradation process
Authors: Kozlov G. V. , Shustov G. B. , Zaikov G. E. 
Published: March 2004

AbstractFractal analysis representations were shown to elucidate quantitative relationships between the parameters of thermooxidative degradation and polymeric melt structure. The process of oxidative consumption during degradation was defined by both the polymer's chemical constitution and the structure of the macromolecular coil. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2840–2844, 2004
Functional barriers in PET recycled bottles. Part I. Determination of diffusion coefficients in bioriented PET with and without contact with food simulants
Authors: Pennarun P. Y. , Dole P. , Feigenbaum A. 
Published: March 2004

AbstractA major outcome for recycled plastics consists of making food packaging materials. However, any contamination of collected plastics with chemicals may then be of concern for public health. A solution to mind migration is to use a layer of virgin polymer, named functional barrier, intercalated between the recycled layer and the food. This article aims to provide experimental values of diffusion coefficients (D) of model pollutants (surrogates) in poly(ethylene terephthalate) (PET) to be used for modeling migration through functional barriers. Diffusion coefficients of a large set of surrogates at low concentrations in PET were measured in various conditions. A solid‐to‐solid diffusion test was designed to avoid the use of a solvent that may induce plasticizing of the material and partitioning effects at the interface. Using [Log D = f(molecular weight)] correlations, the values of diffusion coefficients and activation energies of the surrogates measured by this method were shown to be consistent with the literature data obtained for gases, in permeation experiments, where no plasticization occurred. Migration from PET into food simulants was then studied. Migration into an aqueous medium is largely influenced by the solubility of the surrogates, the less soluble ones being not detected, despite high D values. With ethanol solvent, there were no partitioning effects, and the high plasticization effect of PET by ethanol considerably increases the apparent diffusion coefficients. The effects of temperature and plasticization on the relationship between diffusion coefficients and molecular weight are discussed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2845–2858, 2004
Effects of compatibilization of oxidized polypropylene on PP blends of PP/PA6 and PP/talc
Authors: Abdouss Majid , Sanjani Naser Sharifi , Azizinejad Fariborz , Shabani Mohsen 
Published: March 2004

AbstractThe influence of compatibilization on the dynamic mechanical properties of polypropylene (PP) binary blends with polyamide‐6 (PA6), Talc, and oxidized PP (OPP) was investigated. The oxidation of PP homopolymer was performed in a internal mixer by using air as a oxidizing agent (under atmospheric pressure) and dodecanol‐1 as an accelerator at 180°C for 6½ h [Abdouss, M.; Sharifi‐Sanjani, N.; Bataille, P. J Appl Polym Sci 1999, 36, 10]. In the blends, OPP was used as a blend component and compared with PP over the whole concentration range. Pressed film blends of PP/OPP, PP/OPP/Talc, and PP/OPP/PA6 were examined by dynamic mechanical analyzer, thermal gravimetry analysis, and scanning electron microscopy. Mechanical properties such as tensile strength, modulus of elasticity, elongation, melt flow index, and hardness of the blends were measured. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2871–2883, 2004
Kaolin modified with new resin–iron chelate as flame retardant system for polypropylene
Authors: Shehata A. B. , Hassan M. A. , Darwish N. A. 
Published: March 2004

AbstractPolypropylene's fire‐retardant properties can be improved by using modified kaolin. Modification was done by reaction of kaolin with a prepared resin–iron chelate. Polypropylene samples were loaded with different amounts of kaolin, modified kaolin, and their mixture. Ignition properties of the produced samples were evaluated using cone calorimeter, UL 94, and thermogravimetric analysis techniques. It was found that sample S2 loaded with a mixture of kaolin and modified kaolin had significantly reduced the smoke generation and had a heat release rate comparable to that with kaolin. It was also found that samples S4 and S5 loaded with modified kaolin burned out earlier than did the other samples. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3119–3125, 2004
Multienzyme‐immobilized modified polypropylene membrane for an amperometric creatinine biosensor
Authors: Hsiue Ging‐Ho , Lu Pei‐Lin , Chen Jyh‐Chern 
Published: March 2004

AbstractCreatinine has become an important clinical analyte that is used for the determination of renal and muscular dysfunction. It is essential to determine its concentration in the serum of patients suffering from renal insufficiency. Therefore, an amperometric creatinine biosensor fabricated from a covered platinum/silver electrode with a thin layer of an immobilized multienzyme membrane was studied. Poly(acrylic acid) was introduced onto an argon‐plasma‐treated porous polypropylene membrane surface by graft copolymerization. Subsequently, three different enzymes (sarcosine oxidase, creatinase, and creatininase) were immobilized onto this novel grafted membrane simultaneously via a carbodiimine agent to form a thin layer. The sensor performance was evaluated with a biochemistry analyzer. Moreover, attenuated total reflection/Fourier transform infrared, electron spectroscopy for chemical analysis, and scanning electron microscopy were used to confirm the progression of these reactions. The developed sensor showed a linear detection range of 3.2–320 μM for creatinine in a pH 7.4 buffered solution with 0.1M phosphate. The immobilized multienzyme membrane could be used for at least 3 weeks. The results obtained in our study will hopefully lead to the successful application of modified polypropylene for the development of a creatinine sensor. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3126–3134, 2004
Trace metal ion retention properties of crosslinked poly(4‐vinylpyridine) and poly(acrylic acid)
Authors: Rivas Bernabé L. , Quilodrán Benita , Quiroz Eduardo 
Published: March 2004

AbstractThe crosslinked resins poly(4‐vinylpiridine) (PVPy) and poly(acrylic acid) (PAA) were obtained by radical polymerization. PVPy shows monodentate ligands and PAA at basic pH is basically as acrylate anion, which can contain end‐carboxylates groups or form a bridge acting as mono‐ or bidentate ligands. The retention properties for trace metal ions from saline aqueous solutions and natural seawaters of these two resins were investigated by Batch equilibrium procedure. The metal ions studied were Cu(II), Pb(II), Cd(II), and Ni(II). The following effects were studied: pH, contact time, amount of the adsorbent, temperature, and salinity. The resin PVPy showed a high affinity for Cd(II) and PAA for Cu(II) and Cd(II). The metal ions were determined in the filtrate by atomic absorption spectrometry. By the treatment of the loaded resin with 4M HNO3, it was possible to remove completely the Cu(II) ions. The retention properties of the resins were studied for trace metal ions present in the natural seawaters. Both resins showed a high affinity for Cd(II) when the natural seawater contained Cu(II) and Cd(II). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2908–2916, 2004
Metal ion binding capability of the water‐soluble poly(vinyl phosphonic acid) for mono‐, di‐, and trivalent cations
Authors: Rivas Bernabé L. , Pereira Eduardo , Gallegos Paola , Homper Daniela , Geckeler Kurt E. 
Published: March 2004

AbstractA water‐soluble polymer containing phosphonic acid groups was investigated as a polychelatogen by using the liquid‐phase polymer‐based retention technique (LPR) under different experimental conditions. The maximum retention capacity of this polymer was determined at different pHs and polymer–metal ion ratios. The metal ions investigated were Ag(I), Cu(II), Co(II), Ni(II), and Cr(III). The maximum retention capacity values of the divalent metal ions were very similar and higher than those for the trivalent cations, indicating that the polymer–metal ion interaction was basically through electrostatic type. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2917–2922, 2004
Fabrication of three‐dimensionally ordered microporous membrane by wet phase separation
Authors: Taketani Yuko , Nagaoka Shoji , Kawakami Hiroyoshi 
Published: March 2004

AbstractWe report a novel porous fluorinated polyimide membrane with a cylinder structure fabricated by a wet phase inversion process, which is formed by a ternary system, polyimide/solvent/water. The porous polyimide membranes consisted of a thin top porous layer and three‐dimensionally ordered cylinder micropores. The porous membrane‐forming solvents were N‐methylpyrrolidone containing nonsolvent additives such as alcohol, and the height and width of the cylinder structure were controlled by the solvents. Water fluxes through the porous polyimide membranes were measured using a stirred dead‐end filtration cell, and the fluxes of the porous membrane with the cylinder‐type structure were approximately three times greater than those of the membrane with the finger‐type structure. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3016–3021, 2004
Swelling behavior of chitosan/poly(acrylic acid) complex
Authors: Nge Thi Thi , Hori Naruhito , Takemura Akio , Ono Hirokuni 
Published: March 2004

AbstractThis study investigates the improved swelling behavior of chitosan/poly(acrylic acid) complex by solvent (methanol, ethanol, and acetone) extraction. The complex is developed by photoinitiated free‐radical polymerization of acrylic acid in the presence of chitosan. The swelling ratio of the complexes depends on the cosolvency effect of poly(acrylic acid) to the extracted solvent, which in turn affects the polymer network structure and ionic states characterized by dynamic force microscopy (DFM), Raman, and FT‐IR spectroscopy. The DFM investigation displays the improved structural changes of the polymer network structure after solvent extraction and its relation to the improved swelling property of the chosen system in different environmental conditions (pH, solvent, and salt concentration) are discussed. A high swelling ratio of about 600 times its dry weight is observed in water as well as in low salt and solvent concentration after methanol extraction. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2930–2940, 2004
Synthesis and characterization of propylene‐α‐olefin random copolymers with isotactic propylene sequence. II. Propylene–hexene‐1 random copolymers
Authors: Shin Yong‐Woo , Hashiguchi Hideto , Terano Minoru , Nitta Koh‐hei 
Published: March 2004

AbstractA series of novel hexene‐1–propylene random copolymers with isotactic sequence of propylene was synthesized with a MgCl2‐supported Cr(acac)3 catalyst. The molecular weight distribution of copolymers and homopolymers was considerably narrower than that of typical polyolefins produced by heterogeneous Ziegler–Natta catalysts. The crystallizability of the copolymers having a propylene‐unit content of more than 50 mol % drastically decreased with decreasing propylene‐unit content, and the copolymers with a propylene content of less than 50 mol % were completely amorphous. In the present novel type of random copolymers with crystallizable and noncrystallizable units, a single glass transition was observed between pure polypropylene and polyhexene‐1, and a major component was found to govern the final morphology and the mechanical characteristics. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2949–2954, 2004
Influence of diblock copolymer on the morphology and properties of polystyrene/poly(dimethylsiloxane) blends
Authors: Chuai Chengzhi , Li Shu , Almdal Kristoffer , Alstrup Jan , Lyngaae‐Jørgensen Jørgen 
Published: March 2004

AbstractBlends of polystyrene (PS) and poly(dimethylsiloxane) (PDMS), with and without diblock copolymers (PS‐b‐PDMS), were prepared by melt mixing. The melt rheology behavior of the blends was studied with a capillary rheometer. The morphology of the blends was examined with scanning electron microscopy. The miscibility of the blends was studied with differential scanning calorimetry. The morphology of PS/PDMS blends was modified by the addition of PS‐b‐PDMS copolymers and investigated as a function of the molar mass of the diblock copolymers, viscosity ratios and the processing conditions. As investigated, the observed morphology of the melt‐blended PS/PDMS pair unambiguously supported the interfacial activity of the diblock copolymers. When a few percent of the diblock copolymers blended together with the PS and PDMS homopolymers, the phase size was reduced and the phase dispersion was firmly stabilized against coalescence. The compatibilizing efficiency of the copolymers was strongly dependent on its molar mass. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2747–2757, 2004
Simple method of related sensitivity range to predict the thermodynamic equilibrium morphology of a core–shell latex particle
Authors: Zhao Ke , Sun Peiqin , Liu Dazhuang , Wang Lijun 
Published: March 2004

AbstractThe equilibrium morphologies of different core–shell latices are predicted, and a related sensitivity analysis is given for the predictions. This article proposes a related sensitivity range for estimating the accuracy of predictions, made with the simple method, of the thermodynamically preferred morphology of a core–shell latex particle in two‐stage seeded emulsion polymerization. The related sensitivity range of the predictions is defined and calculated, and the results show that different core–shell latices have different sensitivity ranges. The wider the sensitivity range is, the more reliable the prediction is of the morphology of the core–shell latex. The simple method of related sensitivity range has been verified in the literature and with experiments. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3144–3152, 2004
1,2‐propanediol–cellulose–acrylamide graft copolymers
Authors: Onishi Yasuhiko , Butler George B. , Hogen‐Esch Thieo E. 
Published: March 2004

Abstract1,2‐Propanediol–cellulose–acrylamide graft copolymers (PCACs) were developed for enhanced oil recovery. They were prepared with acrylamide and 1,2‐propanediol (PDO)–cellulose, which was formed through the addition of glycols to cellulose by the Shotten–Baumann reaction between 3‐chloro‐1,2‐propanediol and cellulose. The graft copolymerization was initiated with a redox system between Ce4+ and glycols in cellulose. The infrared spectrum of PDO–cellulose had some characteristic absorption bands around 2960 (νCH) and 1050 cm−1 (νCO) that also appeared for the PDO group and pyranose ring of cellulose, respectively. The rate of Ce4+ consumption by PDO–cellulose was investigated through the calculation of the overall kinetic constant from the slopes of ln(D − DR) versus time (where D is the absorbance and DR is the absorbance of the original polysaccharide solution) The results showed that PDO–cellulose had high reactivity and that there were two mechanisms of oxidation by Ce4+ with PDO–cellulose. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3022–3029, 2004
Synthesis of urethane oils from waste poly(ethylene terephthalate) bottles
Authors: Saravari O. , Vessabutr B. , Pimpan V. 
Published: March 2004

AbstractWaste poly(ethylene terephthalate) (PET) bottles were glycolyzed by propylene glycol (PG) at a weight ratio of PET to PG of 37.5 : 62.5 using zinc acetate as a catalyst. The glycolyzed product, consisting of oligomeric diols with a number‐average molecular weight range of 458–844, was obtained. It was further reacted with soybean oil and toluene diisocyanate to obtain urethane oils at hydroxyl to isocyanate ratios from 1 : 1 to 1 : 0.7, with and without methanol acting as a blocking agent. All the synthesized urethane oils were yellowish, transparent, low‐viscosity liquids of low molecular weights. A lower diisocyanate content and the presence of a blocking agent resulted in higher viscosity, higher molecular weight, and shorter drying time. The films of all synthesized urethane oils exhibited good hardness and adhesion. They also showed excellent water and acid resistance but only fair alkali resistance. However, these prepared urethane oils had lower flexibility and poorer wear resistance compared to those of the commercial urethane oil. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3040–3045, 2004
Response of human chondrocytes on polymer surfaces with different micropore sizes for tissue‐engineered cartilage
Authors: Lee Sang Jin , Lee Young Moo , Han Chang Whan , Lee Hai Bang , Khang Gilson 
Published: March 2004

AbstractResponse of chondrocytes on polymer surfaces is important for applications of tissue‐engineered cartilage, and tissue engineering contains the interaction of cells on material surfaces. We examined the behavior of human chondrocytes cultured on polycarbonate (PC) membranes with different micropore sizes (0.2–8.0 μm in diameter). The adhesion and proliferation of chondrocytes were evaluated by measuring the number of attached cells after 1, 2, and 4 days of culture and morphological observations. It seems that the cell adhesion and proliferation were progressively inhibited, as the PC membranes had micropores with increasing size, probably due to surface discontinuities produced by track‐etched pores. On the PC membrane with smaller micropore sizes, the cells seemed to override these surface discontinuities. Phenotype of chondrocyte was assessed by Safranin‐O staining for anionic sulfated proteoglycans. Chondrocytes on the 8.0 μm‐diameter membrane surface proliferated, on 8 days, formed morphology of round shape, and expressed proteoglycans, because of limitation of spreading by the track‐etched micropores. They maintained their phenotype under conditions that support a round cell shape on the large pore diameter substrate, whereas chondrocyte phenotypes lost on the small pore diameter membranes. In conclusion, this study demonstrated that micropore sizes as well as pore‐to‐pore distance play an important role for adhesion, proliferation, and phenotype of human articular chondrocytes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2784–2790, 2004
Dynamic rheological properties of high‐density polyethylene/polystyrene blends extruded in the presence of ultrasonic oscillations
Authors: Chen Guangshun , Guo Shaoyun , Li Yuntao 
Published: March 2004

AbstractThe linear rheological properties of high‐density polyethylene (HDPE), polystyrene (PS), and HDPE/PS (80/20) blends were used to characterize their structural development during extrusion in the presence of ultrasonic oscillations. The master curves of the storage shear modulus (G′) and loss shear modulus (G″) at 200°C for HDPE, PS, and HDPE/PS (80/20) blends were constructed with time–temperature superposition, and their zero shear viscosity was determined from Cole–Cole plots of the out‐of‐phase viscous component of the dynamic complex viscosity (η″) versus the dynamic shear viscosity. The experimental results showed that ultrasonic oscillations during extrusion reduced G′ and G″ as well as the zero shear viscosity of HDPE and PS because of their mechanochemical degradation in the presence of ultrasonic oscillations; this was confirmed by molecular weight measurements. Ultrasonic oscillations increased the slopes of log G′ versus log G″ for HDPE and PS in the low‐frequency terminal zone because of the increase in their molecular weight distributions. The slopes of log G′ versus log G″ for HDPE/PS (80/20) blends and an emulsion model were used to characterize the ultrasonic enhancement of the compatibility of the blends. The results showed that ultrasonic oscillations could reduce the interfacial tension and enhance the compatibility of the blends, and this was consistent with our previous work. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3153–3158, 2004
Combustion‐thermal‐sprayed recycled poly(ethylene terephthalate)
Authors: Branco José Roberto Tavares , Campos Sthener Rodrigues Vieira , Duarte Luciana Tavares , Lins Vanessa De Freitas Cunha 
Published: March 2004

AbstractThermal‐sprayed polymer coatings have been used as protection against corrosion and wear. In this study, poly(ethylene terephthalate) (PET) powder, which was obtained from postconsumer beverage bottles, was deposited on 1020 steel by low‐velocity flame‐spray technology. The chemical and structural changes in PET due to the thermal‐spray processing were investigated with Fourier transform infrared spectroscopy and X‐ray diffraction. Changes in tribological behavior were examined by pin‐on‐disk testing and three‐dimensional profilometry. The results show that coatings had the same functional groups as the PET beverage bottles. However, the degree of crystallinity was modified. These changes were rationalized in terms of possible structural modifications of the PET polymer. The study showed evidence that the pin‐on‐disk wear developed by an abrasion process through a ploughing mechanism, although a fatigue mechanism could not be disregarded. A low friction coefficient between PET and steel was confirmed. In the as‐sprayed condition, the PET coatings showed higher friction, likely because of a higher coarse debris production rate during the pin‐on‐disk testing. Heat treating the as‐sprayed coating to increase the amorphous PET content improved the sliding behavior by increasing wear resistance. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3159–3166, 2004
Analysis of low‐density polyethylene‐g‐poly(vinyl chloride) copolymers formed in poly(vinyl chloride)/low‐density polyethylene melt blends with gel permeation chromatography and solid‐state 13C‐NMR
Authors: Sombatsompop N. , Sungsanit K. , Thongpin C. 
Published: March 2004

AbstractGel permeation chromatography (GPC) and solid‐state 13C‐NMR techniques were used to analyze the structural changes of poly(vinyl chloride) (PVC) in blends of a low‐density polyethylene (LDPE) and PVC during melt blending. The GPC results showed that the weight‐average molecular weight (Mw) of PVC increased with LDPE content up to 13.0 wt % and then decreased at a LDPE content of 16.7 wt %, whereas the number‐average molecular weight remained unchanged for all of LDPE contents used. The 13C‐NMR results suggest that the increase in Mw was associated with the formation of a LDPE‐g‐PVC structure, resulting from a PVC and LDPE macroradical cross‐recombination reaction during melt blending. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3167–3172, 2004
Synthesis and characterization of new polyamides derived from 4‐(4′‐aminophenyl)urazole and aliphatic diacid chlorides
Authors: Mallakpour Shadpour , Rafiee Zahra 
Published: March 2004

Abstract4‐(4′‐Aminophenyl)urazole (AmPU) was prepared from 4‐nitrobenzoic acid in six steps. The reaction of AmPU with acetyl chloride was performed in N,N‐dimethylacetamide solutions at different ratios, and the resulting disubstituted and trisubstituted amide derivatives were obtained in high yields and were used as models for polymerization reactions. Polycondensation reactions of AmPU with succinyl chloride, suberoyl chloride, and sebacoyl chloride were performed with conventional solution polymerization techniques in the presence of different catalysts, such as pyridine, triethylamine, and dibutyltin dilaurate, and led to the formation of novel aliphatic polyamides. The resulting novel polyamides had inherent viscosities of 0.11–0.22 dL/g in dimethylformamide or H2SO4 at 25°C. These polyamides were characterized with IR, 1H‐NMR, elemental analysis, and thermogravimetric analysis. Some physical properties and structural characterization of these novel polyamides are reported. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3173–3185, 2004