bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gas permeability analysis of photo‐cured cyclohexyl‐substituted polysiloxane films
Authors: Dworak D. P. , Lin H. , Freeman B. D. , Soucek M. D. 
Published: August 2006

AbstractA photo‐cured cyclohexyl‐substituted polysiloxane (PDCHS) film was prepared and compared with polydimethylsiloxane (PDMS) for the determination of permeability coefficients using various penetrants (H2, N2, O2, CO2, CH4, C3H6, and C3H8). Penetrant sorption isotherms and local effective diffusion coefficients as a function of local penetrant concentration were also determined. The crosslink density of the films was measured via dynamic mechanical thermal analysis and was found to be 6.46 × 104 mol/m3 for PDMS and 1.82 × 103 mol/m3 for PDCHS. Photo‐differential scanning calorimetry was used to calculate percent conversion under the conditions used for curing and was found to be (99.6 ± 0.3)% for PDMS and (98.4 ± 0.3)% for PDCHS. When cured, the PDCHS films had a lower crosslink density and lower permeance. It was postulated that the cycloaliphatic substitution along the polysiloxane backbone may not have full rotational ability affording closer intermolecular interactions, thus reducing the available free volume. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2343–2351, 2006
Insert‐molded poly(ether imide)/carbon fiber poly(ether ether ketone) bimaterial composites: Fracture and interfacial analysis
Authors: In Moon Sung , Monson L. L. , Extrand C. W. 
Published: August 2006

AbstractBimaterial composites were constructed by injecting carbon‐fiber‐filled poly(etheretherketone) (CF PEEK) into a mold containing one‐half of a poly(etherimide) (PEI) tensile specimen. Specimens were notched at the interface and tested in tension. Using fracture mechanics, the adhesion strength of the interface (a fracture energy with units of energy per area) was calculated from notch size and stress–strain behavior of the notched specimens. Fracture energies (with units of energy per area) of the PEI/CF PEEK bimaterial composites were slightly less than those measured from the monolithic materials of construction. Variations in test speed (below the glass transition temperature of the two components) had little effect on stiffness or fracture energy. However, fracture energies decreased slightly as temperature increased. Composites fractured through the CF PEEK near the PEI/CF PEEK interface. Consequently, the fracture surface of the PEI portion had a thin layer of CF PEEK (a qualitative indicator of good adhesion). Microscopy and X‐ray photoelectron spectroscopy confirmed the presence of a thin layer of CF PEEK on the PEI. It appears that the miscibility of PEI and PEEK contributed to the strength of the PEI/CF PEEK thermophysical bond. The strength of the thermophysical bond of the PEI/CF PEEK bimaterial composites was greater than the cohesive strength of amorphous commodity polymers such as polystyrene and should be more than adequate for most microelectronics device handling applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2362–2371, 2006
Diffusion of seawater in unsaturated polyester resin and its glass fiber reinforced composites in the presence of titanium dioxide as UV absorber
Authors: Urs M. V. Deepa , Ranganathaiah C. , Ramani R. , Lal Babu , Alam Sarfaraz 
Published: August 2006

AbstractDiffusion of seawater in unsaturated polyester resin (UPR) and its glass fiber reinforced composite in the presence of titanium dioxide has been studied by sorption method. Incorporation of glass and TiO2 to UPR alters the seawater diffusion process from Fickian to non‐Fickian type. The dual mode sorption model is used to separate Fickian‐controlled and relaxation‐controlled diffusion in case of UPR‐T, UPR‐G, and UPR‐GT. The presence of TiO2 seems to stabilize UPR and its glass reinforced samples but an increase in the rate of seawater diffusion is observed for these systems. The free volume determined from positron lifetime measurements support the diffusion data in these systems. Results further indicate that the contribution to diffusion in the later stages of sorption is due to the increased contribution from the interfaces. The plasticizing effect of TiO2 is clearly seen even in the glass reinforced composite. DMA results show an increase in flexibility because of TiO2 presence both in the neat as well as glass reinforced resin which is well supported by decrease in Tg value from DSC data. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2784–2794, 2006
Dispersion polymerization of acrylamide with 2‐acrylamido‐2‐methyl‐1‐propane sulfonate in aqueous solution
Authors: Wu Y. M. , Wang Y. P. , Yu Y. Q. , Xu J. , Chen Q. F. 
Published: August 2006

AbstractThe copolymer of acrylamide (AM) and 2‐acrylamido‐2‐methyl‐1‐propane sulfonate (AMPS) was synthesized through the free radical dispersion polymerization in an aqueous solution of ammonium sulfate and in the presence of poly(2‐acrylamido‐2‐methyl‐1‐propane sulfonate) as stabilizer. The average particle size of the copolymer ranged from 1 to 4 μm, and the molecular weight was from 2.0 × 106 to 7.0 × 106 g mol−1. By analyzing apparent viscosity and particle size, the swelling property of the dispersion copolymer was studied. When the dispersion was diluted with salt water in which the ammonium sulfate concentration kept equal with that of the original dispersion, particle size and particle size distribution of the diluted dispersion changed a little, compared with that of the original dispersion. While diluted with deionized water, particle size and particle size distribution could expand several times. The effects of varying concentrations of the stabilizer, the monomer, the salt and the initiator on particle size, and molecular weight of the copolymer were investigated, respectively. The reaction conditions for preparing stable dispersion were concentrations of 20–28% of the salt, 6–14% of monomers, and 1.8–2.7% of the stabilizer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2379–2385, 2006
A synergistic effect of nano‐Tio2 and graphite on the tribological performance of epoxy matrix composites
Authors: Xian Guijun , Walter Rolf , Haupert Frank 
Published: August 2006

AbstractThe influence of incorporated 300 nm TiO2 (4 vol %), graphite (7 vol %), or combination of both fillers on the tribological performance of an epoxy resin was studied under various sliding load (10–40 N) and velocity conditions (0.2–3.0 m/s). Mechanical measurements indicated that the incorporation of TiO2 significantly enhanced the flexural and impact strength of the neat epoxy and the graphite including epoxy. Tribological tests were conducted with a cylinder‐on‐flat testing rig. The incorporation of nano‐TiO2 significantly improved the wear resistance of the neat epoxy under mild sliding conditions; however, this effect was markedly diminished under severe sliding conditions (high velocity and normal load). Nano‐TiO2 reduced the coefficient of friction only under severe sliding conditions. Graphite showed a beneficial effect in reducing the wear rate and the coefficient of friction of the neat epoxy. Compared to the nano‐TiO2‐filled epoxy, the graphite‐filled epoxy showed more stable wear performance with the variation of the sliding conditions, especially the normal load. A synergistic effect was found for the combination of nano‐TiO2 and graphite, which led to the lowest wear rate and coefficient of friction under the whole investigated conditions. The synergistic effect was attributed to the effective transfer films formed on sliding pair surfaces and the reinforcing effect of the nanoparticles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2391–2400, 2006
Separation of ethylbenzene from C7+‐cut naphtha
Authors: Faridi‐Majidi Reza , Sharifi‐Sanjani Naser , Zand Eissa Khani Ramin , Barari Mohammad 
Published: August 2006

AbstractA fractional distillation process for separating ethylbenzene (EB) from a feed mixture C7+‐cut naphtha, comprising nonaromatics, BTX, EB, styrene, and C8+ fraction, was used. Primarily, 29.63 wt % EB in the bottom was obtained. Redistillation of the bottom component produced 63.98 wt % EB in the 2nd cut; finally, this cut was used as a feed to distillation process and 83.21 wt % EB was obtained in distillate, and this feed was used directly for dehydrogenation process to produce styrene monomer. All of the distilled fractions were analyzed by gas chromatography instrument. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2795–2798, 2006
Smart anionic polyelectrolytes based on natural polymer for complexation of cationic surfactant
Authors: Szczubiałka Krzysztof , Rosół Kamila , Nowakowska Maria 
Published: August 2006

AbstractThe thermosensitive polyelectrolytes were obtained by grafting 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (AMPS) onto hydroxypropylcellulose (HPC), a biodegradable polysaccharide. The interactions of the polymers with dodecyltrimethylammonium chloride (DTAC), a model cationic surfactant, were studied. It was found by the measurements of the surface tension and the analysis of fluorescence emission of pyrene used as a fluorescent probe, that the HPC–AMPS graft polymers strongly interact with DTAC with the formation of polymer–surfactant complexes. The critical aggregation concentrations of these polymer–surfactant systems were found to be of the order of 10−5 mol/dm3. The polymers were found to be potentially useful in the purification of water from cationic surfactants. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2401–2407, 2006
Application of magnetic resonance techniques in investigation of hydrocarbons interaction with composite polymers
Authors: Maddinelli G. , Montanari L. , Ferrando A. , Maestrini C. 
Published: August 2006

AbstractComposite polymers such as high impact poly stirene (HIPS) or acrylonitrile–butadiene–styrene (ABS) are widely used in manufacturing industry. In special applications, such as refrigerator liners, a good resistance to fluids aggression is required. In this study we have applied NMR and ESR techniques to investigate the effect of diffusion of fluids (light hydrocarbons) used as blowing agents for polyurethanes (thermal insulators) inside selected HIPS materials. The application of NMR relaxation analysis on materials exposed to deuterated hydrocarbons (C6D12) allowed selective observation of rubber phase modification. Both longitudinal (T1) and transversal (T2) relaxation provided information on polymer chain dynamics effects, determined by solvent interactions. In fact, a consistent increase in relaxation times of polybutadiene rubber phase after solvent exposition was observed. Similar results were obtained by using hexachlorobutadiene as solvent. Another confirmation was also obtained by spin‐probe ESR technique. This technique could give useful insight into the molecular mobility of the two phases of HIPS. This experimental investigation provided a clear demonstration of consistent solvent penetration inside the rubbery phase of such composite polymers. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2810–2817, 2006
Determination of thermodynamic and transport properties of solvents and non solvents in poly(L‐lactide‐co‐glycolide)
Authors: Eser Hulya , Tihminlioglu Funda 
Published: August 2006

AbstractThermodynamic properties, partition coefficient, and diffusion coefficients of the various solvents (acetone, dichloromethane, trichloromethane, ethyl acetate, ethyl alcohol, tetrahydrofuran, and water) in poly(lactide‐co‐glycolide) (PLGA) at infinite dilution of the solvent have been determined by inverse gas chromatography (IGC). In IGC method, which is based on the characteristic equilibrium partitioning of a solute between a mobile phase and a stationary phase, a small pulse of solvent is introduced into the column and by the aid of retention volume of the solvent, several polymer solvent interaction properties, namely retention volume (Vg), infinitely dilute weight fraction activity coefficient (Ω), Flory–Huggins interaction parameter (χ), and solubility parameters of the polymer (δ) can be determined. The thermodynamic results indicated that trichloromethane and dichloromethane were the most suitable solvents among all the solvents studied for PLGA. The partition (K) and diffusion coefficients (Dp) of various solvents at infinite dilution of the solvent were calculated by using the model developed by Pawlisch et al. (Macromolecules 1987, 20, 1564). The optimum K and Dp values that best fit the data were found and the model predicted experimental data very well. So IGC method is a powerful tool for the determination of thermodynamic and diffusion properties of solvent in polymer at infinite dilution of the solvent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2426–2432, 2006
Porous polyphenylene sulfide membrane with high durability against solvents by the thermally induced phase‐separation method
Authors: Ding Huaiyu , Zeng Yiming , Meng Xiangfu , Tian Ye , Shi Yanqiao , Jiao Qingze , Zhang Shimin 
Published: August 2006

AbstractPorous polyphenylene sulfide membranes were prepared as new solvent‐resistant membranes by the thermally induced phase‐separation (TIPS) method. Porous structures were either formed by solid–liquid phase separation (polymer crystallization) or liquid–liquid phase separation. The effects of solvents, cooling rates, and polymer concentrations on the porous structures were investigated. Various characteristics of pore structure can be obtained with suitable diluents and cooling rates using the TIPS method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2959–2966, 2006
A new macroinitiator for the synthesis of triblock copolymers PA12‐b‐PDMS‐b‐PA12
Authors: Rached R. , Hoppe S. , Jonquieres A. , Lochon P. , Pla F. 
Published: August 2006

AbstractA new PDMS macroinitiator is proposed for the anionic ring‐opening polymerization of lactams. This α,ω‐dicarbamoyloxy caprolactam PDMS macroinitiator was readily obtained in quantitative yield, by an original synthesis scheme in two steps, which involved the scarcely reported reaction of isocyanates with silanol groups. It was then shown that this bifunctional macroinitiator enabled to synthesize triblock copolymers PA12‐b‐PDMS‐b‐PA12 by polymerization of lauryl lactam (LL) at high temperature (200°C) in inert atmosphere under conditions compatible with reactive extrusion processes. Another related high molar weight α,ω‐diacyllactam PDMS macroinitiator was also successfully used in the polymerization of LL under the same conditions, therefore overcoming the limitations formerly reported for this type of macroinitiators during the polymerization ε‐caprolactam (ε‐CL) at a much lower temperature (80°C). Triblock copolymers with a wide range of PA12 /molar weights (Mn: ∼ 10,800–250,000 Da) were eventually obtained by using both types of macroinitiators. DMTA and DSC analyses showed that their thermal properties were strongly dependent upon their respective contents in soft and hard blocks. Such triblock copolymers already appear very promising for the highly effective in situ compatibilization of PA12/PDMS blends as shown by recent complementary results obtained in our laboratory. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2818–2831, 2006
Effects of ammonium dibasic phosphate pretreatment time on the structure and properties of PAN‐based activated carbon hollow fibers
Authors: Sun Junfen , He Chunju , Zhu Sijun , Wang Qingrui 
Published: August 2006

AbstractPolyacrylonitrile (PAN) hollow fibers were pretreated with ammonium dibasic phosphate aqueous solution, then further oxidized in air, carbonized in nitrogen, and activated with carbon dioxide. The effects of pretreatment time of PAN hollow fibers in ammonium dibasic phosphate aqueous solution on the microstructure, specific surface, pore‐size distribution, and adsorption properties of PAN‐based activated carbon hollow fibers (PAN‐ACHF) were studied in this work. After the activation process, the Brunaner–Emmett–Teller (BET) surface area of the PAN‐ACHF and surface area of mesopores in the PAN‐ACHF increases and reaches 513 m2 g−1 and 66 m2 g−1 respectively, when the dipping time of PAN hollow fibers in ammonium dibasic phosphate aqueous solution is 30 min. The adsorptions to creatinine and VB12 of PAN‐ACHF are much high, reach 95% and 86% respectively, when dipping time is 30 min. The dominant pore sizes of mesopores in PAN‐ACHF range from 2 nm to 5 nm. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2448–2453, 2006
Adsorption characteristics of benzene on electrospun‐derived porous carbon nanofibers
Authors: Shim Wang Geun , Kim Chan , Lee Jae Wook , Yun Je Jung , Jeong Young Il , Moon Hee , Yang Kap Seung 
Published: August 2006

AbstractThe adsorption properties of polyacrylonitrile (PAN) carbon nanofibers fabricated by using an electrospinning route were assessed for their applicability as a novel alternative adsorbent. Commercial fiber, A–10, was chosen for comparison. Nitrogen adsorption/desorption isotherms and gravimetric techniques were used to examine the porous structure, adsorption equilibrium, kinetics, and the energetic heterogeneity of the prepared adsorbent. The nitrogen adsorption and desorption isotherms showed that PAN carbon nanofibers are highly microporous with small amounts of mesoporous regions. The equilibrium data of benzene was obtained at three different temperatures (343.15, 383.15, and 423.15) K with pressures up to 4 kPa. The data correlated successfully with the Toth isotherm equation. In addition, by using this isotherm model, the adsorption affinity and isosteric enthalpy of adsorption were determined. The results of the isosteric enthalpy of adsorption and adsorption energy distribution tests/equations revealed that although PAN carbon nanofibers have a heterogeneous surface, they seem to be more homogeneous than commercial carbon fibers. Moreover, the mass transfer and thermal desorption results showed that shallow pores contained within PAN carbon nanofibers may be effective adsorbents for removing toxic compounds. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2454–2462, 2006
Compatibility of PTET‐60/CA blends and separation performance of their membranes for benzene/cyclohexane mixture by pervaporation
Authors: Bai Yunxiang , Qian Jinwen , Zhao Qiang , Xu Yong , Ye Shengrong 
Published: August 2006

AbstractAromatic copolyester of poly(trimethylene‐co‐ethylene terephthalate) (PTET) with different composition was synthesized and the PTET sample with 60% weight fraction of polytrimethylene (PTET‐60) was amorphous. The compatibility of PTET‐60/cellose acetate (CA) blends and the pervaporation of their membranes for separation of benzene/cyclohexane mixtures were investigated. It was found that PTET‐60 is compatible with CA when the weight fraction of PTET‐60 in PTET‐60/CA blends (WPTET‐60) is lower than 0.35 and more than 0.5. Both the degree of swelling (DS) and the permeation flux (J) of these blend membranes increased with increasing WPTET‐60 from 0 to 0.35, and a maximum value of the separation factor (α) displayed at WPTET‐60 = 0.25. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2832–2838, 2006
PSA performances and viscoelastic properties of SIS‐based PSA blends with H‐DCPD tackifiers
Authors: Lim Dong‐Hyuk , Do Hyun‐Sung , Kim Hyun‐Joong 
Published: August 2006

AbstractHotmelt pressure sensitive adhesives (PSAs) usually contain styrenic block copolymers like styrene–isoprene–styrene (SIS), SBS, SEBS, tackifier, oil, and additives. These block copolymers individually reveal no tack. Therefore, a tackifier is a low molecular weight material with high glass transition temperature (Tg), and imparts the tacky property to PSA. The SIS block copolymer with different diblocks was blended with hydrogenated dicyclopentadiene (H‐DCPD tackifier), which has three kinds of Tg. PSA performance was evaluated by probe tack, peel strength, and shear adhesion failure temperature. PSA is a viscoelastic material, so that its performance is significantly related to the viscoelastic properties of PSAs. We tested the viscoelastic properties by dynamic mechanical analysis and the thermal properties by differential scanning calorimeter to investigate the relation between viscoelastic properties and PSA performance. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 2839–2846, 2006
Preparation of (S)‐ibuprofen‐imprinted polymer and its molecular recognition study
Authors: Hung Chin‐Yin , Huang Yun‐Tzu , Huang Han‐Hung , Hwang Ching‐Chiang 
Published: August 2006

AbstractTwo molecularly imprinted polymers (MIPs) were prepared using (S)‐ibuprofen as the template molecule as well as methacrylic acid (MAA) or 4‐vinylpyridine and ethylene glycol dimethacrylate (EGDMA) as the functional monomer and crosslinker, respectively. Free radical polymerization was carried out at 4°C under ultraviolet (UV) radiation. The MIPs thus obtained were ground into 25–44 μm, which were slurry packed into analytical columns. The template molecules were removed by acetic acid/methanol solution (1:9, v/v). high‐performance liquid chromatography (HPLC), with UV detection, was used to evaluate the binding performance of the MIP for the template. The selectivity of (S)‐ibuprofen and naproxen on the host–guest system were assessed using acetonitrile‐based mobile phases. The limits of detection of ibuprofen and naproxen were found to be 0.1844 mmol/L and 0.3264 mmol/L, while the limits of quantitation were 0.6262 mmol/L and 1.0909 mmol/L, respectively. The stationary phase was applied successfully to the commercial tablet analysis. Ibuprofen and naproxen were extracted from tablets with acetonitrile; analysis results showed a good relative standard deviation (RSD) of 0.81–1.24% and accuracy from −4.01 to +2.98% for ibuprofen as well as an RSD of 0.59–0.86% and accuracy from −4.01 to −2.01% for naproxen. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2972–2979, 2006
Non‐isothermal crystallization kinetics and melting behaviors of poly(butylene succinate) and its copolyester modified with trimellitic imide units
Authors: Liu Xiaoqing , Li Chuncheng , Xiao Yaonan , Zhang Dong , Zeng Wan 
Published: August 2006

AbstractWith the help of differential scanning calorimeter (DSC), the basic thermal behaviors, nonisothermal crystallization kinetics, and subsequent melting behaviors of poly(butylene succinate) (PBS) and its copolyester (PBSTMA) modified with trimellitic imide units were investigated in this paper. The DSC thermograms of PBS and PBSTMA showed that the crystallization behaviors of PBS were affected seriously because of the addition of a small quantity of trimellitic imide units. The nonisothermal crystallization processes of them were represented by the Avrami equation modified by Jeziorny and the method developed by Ozawa. After that, the conception of “crystallization rate coefficient (CRC)” introduced by Khanna was employed. The values of CRC for PBS and PBSTMA are 174.6 and 88.2 h–1, respectively. At the end of this paper, the melting behaviors of PBS and PBSTMA after being cooled from 130 to 30°C at different cooling rate were studied in detail. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2493–2499, 2006