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The influence of biaxial deformation on the development of thermal, optical and mechanical properties of PEN and PEN/PEI blends were investigated. The refractive indices in the normal direction of biaxially stretched films decreased with the areal expansion ratio, λ MD λ TD . The Wide angle X-ray results showed that this is caused by the orientation of naphthalene planes...
Flory solution theory modified by Hamada et al. (Macromolecules, 1980, 13, 729) was used to predict the miscibility of blends of poly(ethylene oxide) with poly(methyl methacrylate) (PEO-aPMMA) and with poly(vinyl acetate) (PEO-PVAc). Interaction parameters of a PEO-aPMMA blend with the weight ratio of PEO/aPMMA = 5050 at the temperature range of 393-433 K and PEO-PVAc blends with different compositions...
Cocrystallization in blends of linear and branched polyethylenes has been studied under both isothermal and slow-cooling crystallization conditions. Before the more common, polydisperse-type polyethylenes were studied and the results analysed, model systems were investigated in detail. The components used in the model binary blends were molecular weight fractions of linear polyethylene, hydrogenated...
An analysis of the molecular structure of partially hydrogenated fractions of a monodisperse polybutadiene has been carried out in order to study the nature of the heterogeneous hydrogenation process. The polybutadiene was synthesized by polymerization of butadiene with t-butyl lithium in a non-polar medium. This reaction produces linear polibutadiene chains with about seven 1,2 addition units every...
Bond formation between maleic anhydride grafted polypropylene–polyamide 6 (PP g –PA) blends and polyamide 6 (PA) has been investigated. The fracture energy, G c , of joints formed at various bonding temperatures was measured using a wedge test in a double cantilever beam geometry and compared with that obtained between homopolymers of the constituents. Optical and transmission electron...
The miscibility behaviour of melt-mixed poly(ethylene terephthalate-co-diethylene glycol terephthalate) [PET-co-DEGT] with poly(ethylene oxide) was investigated in all composition ranges. The crystallization of the semicrystalline blend component at different compositions was evaluated by optical microscopy with crossed polarizers. Thermal analysis (d.s.c., t.g.a. and DMA) indicate that the system...
Blends of nylon 6 with the liquid crystal copolyester Vectra have been prepared from the melt with different compositions, and their thermal behaviour has been analysed by differential scanning calorimetry (d.s.c.) and X-ray diffraction (WAXS) using syncrotron radiation, as a function of temperature and thermal treatment. The structural properties of these blends have been found to be very sensitive...
The miscibility of poly(epichlorohydrin)/poly(N-vinyl-2-pyrrolidone) (PECH/PVP) blends was investigated by 13 C cross-polarization combined with magic-angle sample spinning and high-power dipolar decoupling (CP/MAS/DD) techniques. Intermolecular cross-polarization and the downfield shifting of the carbonyl resonance of PVP indicate intermolecular hydrogen bonding. 1 H T 1...
Poly(o-toluidine) (POT) and poly(m-toluidine) (PMT) blends with polystyrene of five different compositions were prepared by solution blending using THF as the solvent in which both the POT-HNO 3 and PMT-HNO 3 bases are almost completely soluble. The blends have been characterized by spectral, thermal and electrical measurements. The results suggest that blend formation occurs at all...
Hydrogen bonds in cellulosic blends with poly(acrylonitrile) (PAN) were characterized in terms of hydroxyl regiochemistry in the cellulosics using Fourier transform infra-red (FTi.r.) spectroscopy. Regioselectively substituted O-methylcelluloses (MC), 2,3-di-O-methylcellulose (23MC) and 6-O-methylcellulose (6MC), were used as cellulosic model components. Wide-angle X-ray diffraction studies of the...
Blends of poly(vinylidene fluoride), PVDF, and poly(o-methoxyaniline), POMA doped with toluene sulfonic acid, TSA, were prepared by casting at various compositions and studied by scanning electron microscopy, X-ray diffraction and differential scanning calorimetry. The blend composition has a great influence on the morphology obtained. As the concentration of POMA-TSA is increased in the blend an...
Co-continuous morphologies are found over a wide composition range (30–80vol%) in blends of a polystyrene thermoplastic and a poly(ether-ester) thermoplastic elastomer when they are blended below the block copolymer's order–disorder transition (ODT). This range decreases with increasing processing temperature and becomes limited when both polymers show pseudo-plastic behaviour. Annealing of the co-continuous...
The effects of maleic anhydride (MA) content and its reactive functionality on the phase size and phase morphology of nylon 6,6/polypropylene (PP) blends were studied. The blends were obtained by simultaneous compounding of maleated styrene-ethylene-butylene-styrene block copolymers (SEBS) containing different amounts of MA, with nylon and PP. The microstructures were examined using cross-polarized...
The compatibilization effect of poly(styrene-b-2-ethyl-2-oxazoline) diblock copolymer, P(S-b-EOx), on immiscible blends of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and poly(ethylene-co-acrylic acid) (EAA) is examined in terms of phase structure and thermal, rheological and mechanical properties, and its compatibilizing mechanism is investigated by Fourier-transform infrared spectroscopy. The block...
Thermal, mechanical, dynamical mechanical and morphological investigations are reported of two series of blends of poly(ethylene terephthalate) (PET) with two nematogenic random polymers synthesized in our laboratory. The nucleant effect of low amounts of the liquid-crystalline component (LCP) is evidenced by thermal analysis for both polymers. At higher LCP contents this effect disappears but a new...
Blends of nylon 6 and ethylene-propylene rubber, grafted with maleic anhydride, (EPR-g-MA) were prepared using a melt blending process. For certain compositions, nylon 6 forms finely dispersed particles due to the reaction of the polyamide amine end groups with the grafted maleic anhydride, that have the potential to reinforce the elastomer matrix. This study focuses on the effects of the content...
Isothermal miscibility maps for blends of styrene-acrylonitrile (SAN) copolymers with methyl methacrylate (MMA) copolymers containing ethyl acrylate (EA) and n-butyl acrylate (nBA) have been determined. The miscibility region for MMA-nBA copolymers is larger than that for MMA-EA copolymers. Binary interaction energies for monomer unit pairs were calculated from critical molecular weight experiments...
Melt rheology, phase morphology and properties of (60/40) isotactic polypropylene/ethylene-co-propylene (iPP/EPR) blends containing EPR copolymer synthesized by means of a titanium based catalyst with very high stereospecific activity (EPR Ti ) were compared to that of (60/40) iPP/EPR blends containing EPR copolymer synthesized by using a traditional vanadium based catalyst (EPR V...
The isothermal crystallization behaviour has been investigated for several compositions of blends between nylon 6 (N6) and the liquid crystal copolyester Vectra using calorimetric and X-ray diffraction techniques. Differences in the crystallization rates have been related to the structural properties of these systems by means of WAXS and SAXS real time experiments using synchrotron radiation. Other...
Co-continuous morphologies in a blend of poly(ether–ester) and polystyrene break up into a droplet/matrix morphology when subjected to a shear flow in a rheometer with a cone–plate configuration and are therefore not stable under shear. It is shown that the capillary number at these flow conditions is too small to maintain stable extended structures that are necessary for a co-continuous morphology...
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