bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication and characterization of cypermethrin nanocapsules in miniemulsion polymerization system
Authors: Xia Chun‐Miao , Zhou Yi‐Feng , Nie Wang‐Yan , Song Lin‐Yong , Dai Ming‐Dong , Xu Xiao‐Ling , Wang Zhen 
Published: May 2012

AbstractThe nanoencapsulation of cypermethrin (CP) was carried out by miniemulsion polymerization, a convenient one‐pot encapsulation technique for nanocapsules. The encapsulation was achieved by polymerization inducing phase separation within minidroplets dispersed in an aqueous phase. For nanocapsules prepared in this way, the type of surfactant and initiator, the level of the crosslinking agent or chain‐transfer agent, and the monomer/CP ratio play a significant role in defining the end morphology of the latex particles. Specifically, for a styrene (St)/CP system, there were optimum levels of ionic surfactant (1.0 wt % sodium dodecyl sulfate), nonionic surfactant [0.5 wt % poly(ethylene glycol) monooctylphenyl ether], oil‐soluble initiator [1.0 wt % azobis(isobutyronitrile)], crosslinking agent (1.0 wt % divinylbenzene), and a St/CP ratio of 1 : 1 for obtaining well‐defined nanocapsules of CP. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Experimental and finite element modeling of vinyl ester nanocomposites under blast and quasi‐static flexural loading
Authors: Almagableh Ahmad , Raju Mantena P. 
Published: May 2012

AbstractMaterials used in blast, penetration, and impact loaded structural applications require high strength and toughness under high strain rate loading. 510A‐40 brominated bisphenol‐A‐based vinyl ester resin was developed and reinforced with different loadings of nanoclay and exfoliated graphite platelet to produce composites with optimal flexural rigidity, vibration damping, and enhanced energy absorption. As these reinforced polymeric materials are viscoelastic in principle, the mechanical behavior was characterized under two extremes of strain rate loading. In this article, the macroscopic response of brominated vinyl ester reinforced with 1.25 and 2.5 wt % nanoclay and exfoliated graphite platelet is considered. Air‐blast experiment was conducted by subjecting these specimens to a high‐transient pressure in a shock‐tube with flexural loading configuration. The axial response was investigated quasi‐statically in a uniaxial tension/compression test and dynamically in a compression Split‐Hopkinson bar test. The servo‐hydraulic MTS system was used to simulate the shock‐tube testing in a flexural quasi‐static loading configuration. High strain rate properties obtained from shock‐tube experiment are compared with that of characterized under the simulated quasi‐static flexural loading. Further, a computational finite element analysis model was developed in ANSYS LSDYNA to predict with reasonable accuracy the dynamic response of shock‐loaded nanoreinforced specimens. Drop in both failure strain and energy absorption was observed with the addition of nanoparticles to pristine vinyl ester. However, an improvement in energy absorption was observed in case of shock‐tube loading at high strain rates as compared to that loaded quasi‐statically. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci., 2012
Drawing and ultimate tenacity properties of polyamide 6/attapulgite composite fibers
Authors: Tsai Fang‐Chang , Li Peng , Liu Zhi‐Wei , Feng Gang , Zhu Ping , Wang Chuen‐Kai , Chen Kan‐Nan , Huang Chi‐Yuan , Yeh Jen‐taut 
Published: May 2012

AbstractThe drawing and ultimate tenacity properties of the Polyamide 6 (PA6)/Attapulgite (ATP) composite fiber specimens prepared at varying modified ATP (mATP) contents and drawing condition were systematically investigated. As evidenced by Fourier transform infrared (FTIR) and morphological analysis, demarcated translucent resins were found firmly attached on the surfaces of ATP nanofibers. The specific surface areas of the mATP specimens reached a maximum value at 381 m2/g as the weight ratios of silane coupling agents to ATP nanofibers reached an optimum value at 1.0. The percentage crystallinity and melt shear viscosity values measured at varying shear rates of PA6x(mATP)y specimens increased consistently as their mATP contents increased. In contrast, melting temperatures of PA6x(mATP)y specimens reduced slightly as their mATP contents increased. At a fixed drawing temperature and rate, the achievable draw ratio (Dra) values of PA6x(mATP)y as‐spun fiber specimens approach a maximum value, as their mATP contents are close to the 0.2 wt % optimum value. The maximum Dra values obtained for PA699.8(mATP)0.2 as‐spun fiber specimens reached another maximum, when their drawing temperatures and rates approached the optimum values at 120°C and 50 mm/min, respectively. At a fixed draw ratio, the tenacity values of PA6x(mATP)y drawn fiber specimens drawn at the optimum drawing temperature and rate reached a maximum value, as their mATP contents approached the 0.2 wt % optimum value. Possible reasons accounting for the interesting morphological, specific surface area, drawing, orientation, and ultimate tenacity properties found for the PA6x(mATP)y fiber specimens are proposed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Polyoxymethylene/thermoplastic polyurethane blends compatibilized with multifunctional chain extender
Authors: Tang Weihua , Wang Huanhuan , Tang Jian , Yuan Huilin 
Published: May 2012

AbstractNovel compatibilized polyoxymethylene/thermoplastic polyurethane (POM/TPU) blends are successfully developed using multifunctional chain extender, Joncryl ADR‐4368, as the compatibilizer. The outstanding compatibilization efficiency of Joncryl on POM/TPU blend was demonstrated by its even higher mechanical properties with only 0.5 wt % of Joncryl than those with 5 wt % of three commonly used compatibilizers. Addition of only 0.5 wt % Joncryl can double the impact strength and significantly improve its tensile strength and flexural strength for POM/TPU (75/25) blend. SEM images show that Joncryl can reduce TPU particle size and enhance the interfacial interactions between POM and TPU. The interparticle distance of TPU in POM/TPU/Joncryl blends was calculated as 0.2 μm, quite close to the critical matrix ligament thickness of POM/TPU blends (0.18 μm). The impact force profile vividly shows that the addition of Joncyl in POM/TPU blends can dramatically increase the total impact energy absorbed by this blend system and enhance the interfacial interactions between POM and TPU. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Electrochemical preparation and characterization of novel polyethylene/polyindene and polystyrene/polyindene composites
Authors: Talu Muzaffer , Uzluk Elif , Sarι Bekir , Selam Leyla 
Published: May 2012

AbstractIn this study, the conducting homopolymer of indene and polyethylene/polyindene (PE/PIn) and polystyrene/polyindene (PS/PIn) composites have been electrochemically synthesized on platinum electrode in nonaqueous acetonitrile. The physical, electrochemical, thermal, and spectral properties of the synthesized PIn and their composites were investigated. The conductivities of PIn and the composites were measured with a four‐probe technique. The conductivity of PIn was determined as 7.86 × 10−4 S/cm, whereas the conductivities of the PE/PIn and PS/PIn composites were determined to 6.42 × 10−5 S/cm and 5.64 × 10−5 S/cm, respectively. From Gouy scale magnetic susceptibility measurements, it was found that PIn and the composites had bipolaron natures. Fourier transform infrared spectra were taken to analyze the structural properties of PIn and the composites. The thermal properties of PIn and the PE/PIn and PS/PIn composites were investigated with thermogravimetric analysis, and it was found that they showed adequate thermal stability. According to the initial decomposition temperature among the composites, the composite including PE had the highest decomposition temperature with 450°C. The synthesized composites were different in aspect of morphology when compared to PIn. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Quantification of styrene–butadiene rubber swelling as a function of the toluene content in gasoline: A new method to detect adulterations of fuels
Authors: Takeshita Elaine V. , Piantola Felipe A. , de Souza Selene M. A. G. U. , Nunes Regina C. R. , de Souza Antônio A. U. 
Published: May 2012

AbstractThe swelling of styrene–butadiene rubber (SBR) when exposed to organic solvents was measured and mathematically correlated to the toluene concentration in a complex mixture such as gasoline. This relation enables inferences to be made regarding the composition and quality criteria of the fuel and represents a new method to detect adulterations. Changes in the mass and volume were measured by gravimetric and hydrostatic techniques. A simplex‐lattice experimental mixture design was carried out in mixtures with toluene, heptane, and type C gasoline (a blend of gasoline with ethanol) and the mass swelling was statically analyzed for 5 and 15 min of continuous immersion in the mixtures of the solvents. For the experimental design two cubic equations were obtained with a high value for R2‐ajusted (>0.98) at 25°C ± 1°C correlating mass swelling of SBR and the content of solvents. For both immersion times, the greatest and most important effect over the mass swelling was the content of toluene, with the mass variations increasing proportionally with toluene content in the gasoline. The analysis of variance applied to the mass swelling data verified that it is possible to obtain good mathematical equations to associate the rubber swelling with the solvent composition and concentration. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The use of poly(amidoamine) dendrimer in modification of jute for improving dyeing properties of reactive dyes
Authors: Zolriasatein Ali Akbar , Yazdanshenas Mohammad Esmail , Khajavi Ramin , Rashidi Abosaeed , Najafi Farhood 
Published: May 2012

AbstractIn this study, the poly(amidoamine) (PAMAM) G‐2 dendrimer was applied to the jute yarn. Fourier transform infrared spectrophotometry (FTIR) of the dendrimer‐treated jute yarn indicated that all carbonyl groups of the jute fiber have reacted with amino groups of the PAMAM dendrimer. Jute yarns which had been pretreated with PAMAM dendrimer displayed markedly enhanced color strength with reactive dyes, even when dyeing had been carried out in the absence of electrolyte or alkali. Dendrimer‐treated jute yarn showed much better light‐fastness than that of untreated jute yarn. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Thermal decomposition kinetic and flame retardancy of CaCO3 filled recycled polyethylene terephthalate/recycled polypropylene blend
Authors: Thumsorn Supaphorn , Yamada Kazushi , Leong Yew Wei , Hamada Hiroyuki 
Published: May 2012

AbstractThe flammability and thermal decomposition kinetics of recycled polyethylene terephthalate (RPET)/recycled polypropylene (RPP) blends filled with CaCO3 were investigated. The thermal decomposition kinetics were determined by using various models such as the Flynn‐Wall‐Ozawa, Kissinger, and Kim‐Park, which would define the thermal stability of the blends through the determination of their decomposition activation energies. Meanwhile, the flammability of the materials was also determined through the limiting oxygen index (LOI) method. It was found that blends with higher RPP content or contain CaCO3 exhibited higher resistance to thermal degradation judging from their higher activation energies. Furthermore, it was found that the isoconversion kinetic of the Flynn‐Wall‐Ozawa model could provide a better estimation of the decomposition activation energy at each stage of degradation. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and properties of MWCNTs/poly(acrylonitrile‐ styrene‐butadiene)/epoxy hybrid composites
Authors: Jyotishkumar P , Abraham Eldho , George Sajeev Martin , Elias Eldho , Pionteck Jürgen , Moldenaers Paula , Thomas Sabu 
Published: May 2012

AbstractPoly(acrylonitrile‐styrene‐butadiene) (ABS) was used to modify diglycidyl ether of bisphenol‐A (DGEBA) type epoxy resin, and the modified epoxy resin was used as the matrix for making multiwaled carbon tubes (MWCNTs) reinforced composites and were cured with diamino diphenyl sulfone (DDS) for better mechanical and thermal properties. The samples were characterized by using infrared spectroscopy, pressure volume temperature analyzer (PVT), thermogravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), thermo mechanical analyzer (TMA), universal testing machine (UTM), and scanning electron microscopy (SEM). Infrared spectroscopy was employed to follow the curing progress in epoxy blend and hybrid composites by determining the decrease of the band intensity due to the epoxide groups. Thermal and dimensional stability was not much affected by the addition of MWCNTs. The hybrid composite induces a significant increase in both impact strength (45%) and fracture toughness (56%) of the epoxy matrix. Field emission scanning electron micrographs (FESEM) of fractured surfaces were examined to understand the toughening mechanism. FESEM micrographs reveal a synergetic effect of both ABS and MWCNTs on the toughness of brittle epoxy matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Dynamic mechanical analysis of magnetic tapes at ultra‐low frequencies
Authors: Rummel Nicholas J. , Weick Brian L. 
Published: May 2012

AbstractA custom, ultra‐low frequency, dynamic mechanical analyzer (ULDMA) has been developed to study the correlated effects of temperature and frequency on the viscoelastic behavior of magnetic tapes. It has been used to acquire data needed for the development of future magnetic tapes that require an archival life of up to 100 years. A range of elevated temperatures is used to simulate real‐world storage environments, which enables the investigation of how the viscoelastic characteristics of tape samples influence the extent to which the tape deforms. The experiments and subsequent analysis examine the influence of the molecular structure on the viscoelasticity of magnetic tapes. Experiments were performed on a variety of magnetic tapes, including poly(ethylene terephthalate) (PET), poly(ethylene naphthalate) (PEN), metalized PET (M‐PET), and metalized Spaltan (M‐SPA). Additional experiments examined PEN and PET substrates by removing the front and back magnetic layers from the tape sample. Because of the viscoelastic behavior of the tapes, a time delay was present between the strain and stress signals, which was determined using a Fourier transform program. The elastic modulus (E), storage modulus (E′), loss modulus (E″), and loss tangent (tan δ) were obtained from the time delay for each of the ULDMA experiments at 25, 50, and 70°C over the frequency range of 0.0100–0.0667 Hz. Plots of these mechanical characteristics demonstrate the ability of frequency and temperature to affect trends associated with mechanical and thermal properties. Finally, some samples displayed an initial relaxation during the ULDMA experiments, which, when modeled using Maxwell's viscoelastic model, provided an insight into the relaxation characteristics of the samples. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and characterization of novel aromatic polyamides bearing CF3, quinoxaline‐anthraquinone pendants: Study of photophysical and electrochemical properties by using nanocomposite electrode paste
Authors: Ghaemy Mousa , Masoumi Arameh , Nasab Seyed Mojtaba Amini , Hassanzadeh Marjan 
Published: May 2012

AbstractA new aromatic diamine, 2,3‐bis(4‐(4‐amino‐2‐(trifluoromethyl) phenoxy)phenyl)naphtho[2,3‐f]quinoxaline‐7,12‐dione, was synthesized and fully characterized by using FTIR, 1H and 13C NMR, DEPT technique, and elemental analysis. A series of novel fluorescent anthraquinone‐quinoxaline containing polyamides (PAs) with inherent viscosities of 0.39–0.62 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many polar aprotic organic solvents and could be solution‐cast into tough and flexible films. The PAs exhibited glass transition temperatures (Tg)s between 230 and 323°C, and 10% weight loss temperatures in the range of 362–433°C in N2. All of the PAs have fluorescence emission in solution and in solid state with maxima around 452–510 nm and with the quantum yields in the range of 6–17%. Also, cyclic voltammetry (CV) method was used to study the electrochemical oxidation behavior of these polymers at the surface of a modified multiwalled carbon nanotube (MWCNT)s glassy electrode. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and properties of TiO2‐filled poly(acrylonitrile‐butadiene‐styrene)/epoxy hybrid composites
Authors: P Jyotishkumar , Pionteck Jürgen , Moldenaers Paula , Thomas Sabu 
Published: May 2012

AbstractPoly (acrylonitrile‐butadiene‐styrene) (ABS) was used to modify diglycidyl ether of bisphenol‐A type of epoxy resin, and the modified epoxy resin was used as the matrix for making TiO2 reinforced nanocomposites and were cured with diaminodiphenyl sulfone for superior mechanical and thermal properties. The hybrid nanocomposites were characterized by using thermogravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), universal testing machine (UTM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The bulk morphology was carefully analyzed by SEM and TEM and was supported by other techniques. DMA studies revealed that the DDS‐cured epoxy/ABS/TiO2 hybrid composites systems have two Tgs corresponding to epoxy and ABS rich phases and have better load bearing capacity with the addition of TiO2 particles. The addition of TiO2 induces a significant increase in tensile properties, impact strength, and fracture toughness with respect to neat blend matrix. Tensile toughness reveals a twofold increase with the addition of 0.7 wt % TiO2 filler in the blend matrix with respect to neat blend. SEM micrographs of fractured surfaces establish a synergetic effect of both ABS and TiO2 components in the epoxy matrix. The phenomenon such us cavitation, crack path deflection, crack pinning, ductile tearing of the thermoplastic, and local plastic deformation of the matrix with some minor agglomerates of TiO2 are observed. However, between these agglomerates, the particles are separated well and are distributed homogeneously within the polymer matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Mechanism and kinetics of oxidation during the thermal stabilization of polyacrylonitrile fibers
Authors: Xiao Shijie , Cao Weiyu , Wang Bin , Xu Lianghua , Chen Biaohua 
Published: May 2012

AbstractThe thermal behavior and structural evolution during the thermal stabilization of polyacrylonitrile (PAN) fibers in N2 and air were investigated using differential scanning calorimetry and solid‐state 13C nuclear magnetic resonance. It was found that an oxidation reaction, that generated carbonyl (CO) groups could occur at 160°C which has not been reported in the literature. It is proposed that the cyclized structures in the PAN macromolecule chains are a prerequisite for the oxidation. Further investigations indicate that with more cyclized structures in the PAN macromolecule chains, the oxidation proceeds more readily, which is consistent with the proposed mechanism. The kinetic parameters for the oxidation and cyclization reactions were estimated using the Kissinger method. The activation energies for the reactions of oxidation and cyclization for PAN fibers are about 96.4 kJ/mol and 190.0 kJ/mol, respectively, which implies that the cyclization is the rate determining step during the thermal stabilization of PAN fibers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and characterization of poly(hydroxylic fluoroacrylate)/mSiO2 nanocomposite by in situ solution polymerization
Authors: Liu Hu , Fu Baosong , Shang Qianqian , Xiao Guomin 
Published: May 2012

AbstractIn this study, vinyl‐group modified nanosilicas (mSiO2) were prepared via sol–gel method using vinyltriethoxysilane (VTES) as modifier first, then the novel poly(hydroxylic fluoroacrylate)/mSiO2 nanocomposite was successfully synthesized by in situ solution polymerization of mSiO2 with dodecafluoroheptyl methacrylate (DFHMA), β‐hydroxyethyl methacrylate (HEMA), methyl methacrylate (MMA), and butyl acrylate (BA) initiated by 2,2‐azobisisobutyronitrile (AIBN) in the co‐solvents of ethyl acetate and butyl acetate. The chemical composition and structure of the nanocomposite were characterized by Fourier transform infrared spectrometry (FTIR) and transmission electron microscopy (TEM). TEM observation indicated that mSiO2 nanoparticles obtained a well dispersion in polymeric matrix. Thermogravimetric analysis (TGA) studies revealed that the temperature corresponding to 50% weight loss of the nanocomposite was improved by 21.5°C with the addition of 2.0 wt % mSiO2. The synthesized nanocomposites were applied to use with hexamethylene diisocyanate trimer (HDIT) to prepare polyurethane materials. Tensile test revealed that polyurethane material with mSiO2 content of 2.0 wt % showed an ultimate tensile strength of about 5.19 times higher than that without mSiO2. The polyurethane films displayed surface energy of lower than 25 mN m–1 and high light transmittance. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Dually stimuli‐responsive hyperbranched polyethylenimine with LCST transition based on hydrophilic–hydrophobic balance
Authors: Xia Yumin , Wang Jia , Xu Su , Liao Qian , Zhu Xinyuan , Wang Yanping , Wang Yimin 
Published: May 2012

AbstractDually stimuli‐responsive hyperbranched polyethylenimine derivatives (HPEI‐star‐PPOs) were successfully synthesized through Michael addition of commercial HPEI, poly(propylene oxide) dimethacrylate, and 2‐mercaptoethanol. In aqueous solution, these HPEI‐star‐PPOs exhibited response to temperature and pH. The corresponding lower critical solution temperature (LCST) could be readily adjusted by changing the feed ratio of HPEI to PPO, which also presents the ratio of hydrophilicity to hydrophobicity, indicating that this LCST transition is based on hydrophilic–hydrophobic balance. Because of the tertiary amine as well as unreacted primary or secondary amine that can be protonated during pH decreases, HPEI‐star‐PPOs exhibited a pH‐dependent thermoresponse. The 3‐(4,5‐dimethyl‐thiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide assay against COS‐7 cells demonstrated that HPEI‐star‐PPO had relatively low cytotoxicity compared to HPEI. All these characteristic suggest that this stimuli‐responsive polymer is a promising functional material for biomedical applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and application of 2‐acrylamido‐2‐methyl propane sulfonic acid/acrylamide/N,N‐dimethyl acrylamide/maleic anhydride as a fluid loss control additive in oil well cementing
Authors: Guo Shenglai , Bu Yuhuan 
Published: May 2012

AbstractUsing 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS), acrylamide (AM), N,N‐dimethyl acrylamide (NNDMA), and maleic anhydride (MA), a new dispersive type fluid loss control additive (FLCA) AMPS/AM/NNDMA/MA (PANM) was synthesized by free radical aqueous solution copolymerization, and the new FLCA could be used without dispersant existing in the cement. The optimal PANM (OPANM) was obtained under the optimum reaction conditions: mole ratio of AMPS/AM/NNDMA/MA = 4/2.5/2.5/1, monomer concentration = 32.5%, amount of (by weight of monomer) ammonium persulfate/sodium bisulfate = 1.0%, pH value = 4, and temperature = 40°C. The synthesized copolymer OPANM was identified by FTIR analysis. The evaluation results show the OPANM has excellent dispersing power, fluid loss control ability, thermal resistant, and salt tolerant ability. The OPANM was even stable when the temperature was below 300°C proved by TG analysis. The thickening time of the slurry containing the synthesized additive reduces as the temperature increases. The copolymer OPANM is expected to be an excellent FLCA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013