The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The conditions for processing and doping of blends of poly(o-alkoxyaniline)s and poly(vinylidene fluoride) were investigated. Flexible, free-standing and stretchable films of blends of various compositions were obtained by casting. A low percolation threshold was observed with the onset of conductivity at low polyalkoxyaniline contents (i.e. 5%). Interestingly, these blends displayed electrochromism...
I.r. and high-resolution solid-state 13 C n.m.r. spectra, as well as proton relaxation times T H1 andT H1ρ of poly(ethylene oxide) (PEO)/atactic poly(methyl methacrylate) (a-PMMA) blends in the solid state, with PEO weight fractions of 10, 30, 50 and 70% were measured. Infra-red spectra of pure PEO with various molecular weights were also measured. The...
An analysis has been carried out of the crystalline structure of a blend consisting of amorphous polycarbonate and semicrystalline isotactic polypropylene (PP) crystallized under pressure. Structure investigations were carried out by means of wide-angle X-ray scattering. The amount of particular phases as well as the degree of crystallinity have been analysed. It was found that during pressure...
The phase behaviour of binary blends of styrene-methacrylonitrile (SMAN) copolymers and methyl methacrylate copolymers with cyclohexyl methacrylate and t-butyl methacrylate has been determined as a function of composition of each copolymer at 130, 150 and 180°C. These miscibility maps are compared with those of recently reported blends of styrene-acrylonitrile (SAN) copolymers with methacrylate copolymers...
Blends of poly(ethylene terephthalate) (PET)/poly(ethylene-co-ethyl acrylate) were found to have good mechanical properties when melt-mixed at optimum conditions, i.e. at 290°C for 25 min. Characterization studies based on tensile testing, dynamic mechanical analysis, differential scanning calorimetry and Fourier transform infra-red spectroscopy of blend extracts and morphological evidence using...
A brief literature survey is presented on the models predicting the composition dependence of fracture properties of heterogeneous polymer systems. Some of the models cannot predict composition dependence properly or are limited to a narrow composition range, while more exact ones are difficult to use because of their complexity. A different approach is presented, which takes into consideration...
Miscibility in the binary system of deuterated polystyrene and lightly sulfonated polystyrene has been investigated. Small-angle neutron scattering was used to evaluate the physical state of deuterated polystyrene/polystyrene-1.67% sulfonic acid blends over a wide composition range. Scattering behaviour was found to agree with the Debye-Bueche theory indicating that the blends were phase-separated...
Styrene copolymers containing about 4.3, 7.5 and 13.3 mol% of 4-vinylbenzenephosphonic acid (VBPA) as comonomer units were synthesized. The copolymers were insoluble in common organic solvents, possibly because side reactions involving the phosphonic acid groups had occurred during the drying process. Upon adding a small amount of concentrated hydrochloric acid to tetrahydrofuran, the polymer became...
In this paper the interactions of poly(monoethyl itaconate) with poly(2-vinylpyridine) and poly-(4-vinylpyridine) have been studied. Polymer blends or polycomplexes can be obtained, depending on the solvent employed. The stoichiometry found for the polycomplexes obtained was 2:1 of monoethyl itaconate:pyridine repeat units. Polymer complexes do not show a standard glass transition temperature. ...
The phase behaviour of blends of poly(methyl methacrylate) (PMMA) and poly(styrene-co-acrylonitrile) (SAN) is calculated as a function of copolymer composition from the data of the temperature dependence of all three segmental interaction parameters, χij (T) of the system SAN/PMMA, i.e. χS (T), χAN (T) and χS (T). Using blends with different...
The formation of a microphase and a macrophase in solvent-cast homopolymer/block copolymer blends, where the homopolymer is exothermically miscible with one of the block copolymer segments, is demonstrated to depend on the molecular weights of the homopolymer and the incompatible segment of the block copolymer, in spite of the exothermic mixing. Binary blends of poly(vinyl chloride) (PVC) with poly(n-butyl...
The electron spin resonance (e.s.r.) spectra of poly(2-ethyl hexyl methacrylate) (PEHMA) spin-labelled with nitroxide end groups were recorded over a temperature range for both the pure, bulk polymer and for 1 : 1 (w/w) immiscible blends with poly(methyl methacrylate) (PMMA) and polystyrene (PS). Both PMMA and PS have significantly higher glass transition temperatures than PEHMA, with which they...
The compatibility of ionomer/polymeric acid blends has been studied for polymer pairs consisting of sodium salts of sulfonated polystyrene and methyl methacrylate-methacrylic acid copolymer using dilute solution viscometry. The intrinsic viscosities of the blends, prepared in three different weight fractions (25, 50 and 75%) using the solution-blending technique, were measured in two solvents with...
The coarsening of phase-separated domains in a molten blend of two ethylene-octene copolymers has been observed by studying electron micrographs of rapidly quenched samples. Blends containing 10% of a 2 mol% ethylene-octene copolymer (with 90% of an 8 mol% ethylene-octene copolymer) were held in the melt for various times at a temperature at which phase separation was known to take place. The diameters...
Nitrated polyetherimide (NI-PEI) was obtained by chemically modifying a commercially available polyetherimide (PEI) and was characterized by nuclear magnetic resonance and infra-red spectroscopies, elemental analysis and viscometry. NI-PEI and NI-PEI/PEI mixtures were blended with an epoxy resin (MY0510) which was cured with 3,3 -diaminodiphenolsulfone. The morphology and fracture behaviour of...
The effect of several parameters such as molecular weight, chemical composition and architecture of the interfacial agent on the dispersed particle size is investigated in polystyrene/ethylene-propylene rubber blends. The study is based on the dependence of the dispersed phase size versus the concentration of interfacial modifier, the so-called emulsification curves. A critical concentration value...
Poly(N-methyllaurolactam) (PNMLL) and its blends with poly(4-vinylphenol) (PVPh) were studied by a combination of infra-red, Raman and n.m.r. spectroscopic methods. In the crystalline phase of semicrystalline PNMLL, the amide bond was shown to be present in the cis form, and the polymethylene chain to contain long trans sequences, with a rans conformation on the -CH 2 CO- bond. In the blends,...
Morphology and mechanical properties of blends of isotactic polypropylene (PP) and nitrile rubber (NBR) have been investigated with special reference to the effects of blend ratio. Morphological observations of blends showed a two-phase system, in which the rubber phase was dispersed as domains in the continuous PP matrix at lower proportions of NBR (≤50%). The 30 PP/NBR blend was found to exist...
Two types of elastomers grafted with maleic anhydride (MA), an ethylene-propylene random copolymer 9EPR) and a styrene-ethylene/butylene-styrene triblock copolymer (SEBS) were found to function both as impact modifiers and compatibilizers for nylon 6/polypropylene blends. The maleic anhydride grafted to the rubber reacts with the amine end-groups of the polyamide, forming a rubber-nylon 6 graft copolymer...
The morphology of nylon 6/polypropylene blends modified with maleated rubbers, such as styrene-ethylene/butylene-styrene triblock copolymers (SEBS-g-maleic anhydride (MA)) and ethylene-propylene random copolymers (EPR-g-MA), is affected by changes in the level of functionality of the rubber. By adjusting this level of functionality it is possible to induce drastic changes in the morphology of blends...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.