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The influence of two natural terpene resins on the morphology, phase structure and isothermal crystallization process of iPP was investigated by optical (OM) and electron microscopy (SEM) and differential scanning calorimetry (DSC). It was found that in dependence on temperature, composition and chemical nature of the resin, one, two or three phases can be present. The isothermal spherulite growth...
Blends of nylon 6 and polyethylene were investigated over a range of compositions. The polyethylenes used were grafted with maleic anhydride and, thus, have the potential to react with the amine end groups of nylon 6 during melt processing. This study focuses on the effects of the concentration, viscosity and functionality of the maleated polyethylenes (PE-g-MA) on the rheological, morphological,...
Blends of a 100 penetration grade bitumen with four different polyethylenes having up to 40pph or 29% of polymer by weight were prepared using a Z-blade mixer at more than 160 o C. The blends were studied by fluorescence optical microscopy, differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). The optical measurements indicated the presence of bitumen-rich...
Stable co-continuous morphologies are found over a wide composition range in blends of styrene/(ethylene-butylene) based block copolymers (SEBS) and polypropylene (PP) when they are processed below the block copolymer's order-disorder transition (ODT), i.e. when the block copolymers are microphase-separated. Blending at higher temperatures, i.e. when the block copolymer shows a single-phase melt,...
The synthesis of styrene–pentabromobenzyl acrylate (S–PBBA) and methyl methacrylate–pentabromobenzyl acrylate (MMA–PBBA) copolymers and the phase behavior of their blends is reported. The miscibility of S–PBBA copolymers with polystyrene (PS), tetramethyl polycarbonate (TMPC), and poly(phenylene oxide) (PPO), and of MMA–PBBA copolymers with poly(methyl methacrylate) (PMMA) and polycarbonate (PC) was...
The sorption and diffusion of a series of aromatic hydrocarbons through blends of isotactic polypropylene/nitrile rubber have been investigated. The effects of blend ratio, vulcanizing systems and different fillers on the transport behavior were studied. In the blends, the uptake and diffusion coefficient increase with an increase in rubber concentration, and decrease with the molar volume of solvents...
The miscibility of polybenzimidazole {poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole], (PBI)} and a polyimide {poly[2,2′-bis(4-(3,4-dicarboxyphenoxy)phenyl)propane-m-phenylenediimine] (PI)} was studied in the entire composition range. Films were cast from solution by a procedure developed in a preliminary work. The blends were studied by FT-IR spectroscopy, thermal and thermomechanical methods, and...
The effects of dynamic crosslinking on rheological, mechanical and dynamic mechanical properties of high density polyethylene (HDPE) and acrylonitrile butadiene rubber (NBR) blends have been evaluated with special reference to the effect of dosage of crosslinking agent. The morphology has been studied using scanning electron microscope. Both the microscopy and dynamic mechanical analysis indicate...
In this paper, the influence of the addition of a copolymer on the interface, molecular orientation and properties of biaxially stretched PP–PET is studied. For most homopolymers, biaxial stretching results in an improvement of the properties caused by chain orientation. Blending with a second homopolymer and creation of a multiphase system leads to the occurrence of decohesion phenomena between both...
Mechanical properties of polymer blends with co-continuous morphologies were measured and compared to the properties of blends of the same polymers with a droplet/matrix morphology. For this purpose, poly(ether–ester)/PS and SEBS/PP blends were prepared with both morphologies, which was facilitated by the rheological properties of the block copolymers. The elastic moduli of co-continuous blends were...
Crystallization behavior of blends of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL) prepared by solution casting has been investigated by differential scanning calorimetry (DSC). In the study of PHBV/PCL blends by DSC, crystallization temperature of PHBV in the blends decreased about 8-12 o . From the results of the Avrami analysis of PHBV in the PHBV/PCL blends,...
The coarsening of co-continuous morphologies in polymer blends with annealing is studied, demonstrating the effect of interfacial tension, viscosity and also physical cross-links in blends with thermoplastic elastomers. Co-continuous morphologies of 50/50wt% stay co-continuous with annealing but show a linear increase in phase size with time. The 30/70wt% blends break up into droplet/matrix morphologies...
The phase behaviour and interaction parameters of binary blends of copolymers involving cyclohexyl methacrylate (CHMA), methyl methacrylate (MMA) and various styrene derivatives (styrene (S), α-methylstyrene (AMS) and p-methylstyrene (PMS)) are examined using the lattice fluid theory of Sanchez and Lacombe. ‘Bare’ interaction parameters (ΔP∗ij) for various monomer unit pairs were deduced where possible...
Toughening mechanisms in blends containing 60 parts nylon 6,6, 20 parts polypropylene (PP) and 20 parts styrene–ethylene/butylene–styrene (SEBS) grafted to different levels of maleic anhydride (MA) were investigated. The sequence of events was carefully characterised using different microscopic techniques. It was found that under triaxial constraint interfacial cavitation followed by multiple crazing...
Blends of a 100penetration grade bitumen have been prepared at 180°C with five different polyolefins, each in four different proportions (10, 20, 30 and 40 pph). They have been examined by fluorescence microscopy at ambient temperatures, and by DSC and DMTA over a wide temperature range. DSC indicated that the melting points of crystallites formed on cooling the blends were about 10°C lower than for...
Copolymers of tribromostyrene (TBS) with styrene (S) and methyl methacrylate (MMA) were synthesized. The miscibility regions for blends of STBS copolymers with the homopolymers polystyrene (PS), poly(2,6-dimethyl-1,4-phenylene oxide) (PPO), tetramethyl bisphenol A polycarbonate (TMPC), as well as blends of MMA–TBS copolymers with poly(methyl methacrylate) (PMMA) were determined. Blends of MMA–TBS...
Poly(3-hydroxybutyrate) (PHB) has been blended with poly(vinyl acetate) (PVAc) and the system has been found to be miscible over the complete composition range studied, i.e. 0-100wt%. The blends exhibited a single glass transition temperature, which varied with composition between the limits of the two homopolymers. Positive deviation from a linear dependence of the glass transition temperature with...
Sanchez-Lacombe (SL) lattice-fluid theory was used to predict the miscibility of the PEO/PVAc blending system. Integral interaction parameters, g of this polymer pair were calculated by using SL theory. And the effect of the temperature, composition of blends and molecular weight of PVAc on the extent of their miscibility has been discussed.
The miscibility of cyclic poly(methylphenylsiloxanes) (PMPS) with molar masses less than 1000gmol -1 have been studied in mixtures with either cyclic or linear poly(dimethylsiloxane) (PDMS). In all cases, an upper critical solution temperature (UCST) was observed and interaction parameters were determined from the phase boundaries. The results were compared with those from our previous...
Thermoplastic polysulfone (PSF) was melt blended with a novel oligomer poly(bisphenol-A) (m-BPA) to produce samples of varying composition by weight PSF/m-BPA of 99/1, 95/5, 90/10, and 58/42. Miscibility studies, performed via differential scanning calorimetry and dynamic mechanical spectroscopy, show a single Tg, intermediate to the pure component Tgs, over the composition range of 1–42wt% oligomer...
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