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By means of a Nicolet area detector, the crystallite orientation of uniaxially multi-step drawn poly(ethylene terephthalate) (PET) film strips with large draw ratios from 5.4 to 7.3 has been studied. As orientation parameters, cos n φ , P 2 (cos φ) and P 4 (cos φ) were determined from the equatorial wide-angle X-ray scattering reflexes (0 1 0), (1 1 0) and (1 0...
Polyaniline doped with poly(alkylene phosphates) has been studied by Fourier transform infra-red, X-ray photoelectron and ultraviolet/visible spectroscopies. The protonation of the polymer was indicated by the appearance of infra-red modes characteristic of polyaniline salts and by the bands typical of polyphosphates at ca. 1000 cm -1 . X-ray photoelectron spectra showed a decrease...
A quantitative 13 C nuclear magnetic resonance analysis of an ethylene-propylene copolymer produced on a modern high-field instrument produces a spectrum with eight discrete groups of peaks. Assignment of these peaks provides eight simultaneous equations to describe the six triad distribution numbers. We have demonstrated the advantages of solving directly this over-determined set of...
Microdeformation in thin films of rubber modified poly(methyl methacrylate) has been investigated using TEM. The effects of two-layer core-shell particles with rubbery cores, and three-layer particles with glassy cores are compared. While the former undergo relatively coarse cavitation and may act to block fibril drawing in matrix crazes, the rubber shell of the three-layer particles tends to fibrillate,...
The electrochemical behaviour of the silylene-phenylene, silylene-thienylene, silylene-diphenylene and silylene-anthranylene copolymers was investigated using cyclic voltammetry. The oxidation potentials of these organosilicon copolymers decreased with increasing dimethylsilylene chain length. The change of the oxidation potential was explained by considering the σ-π conjugation between the dimethylsilylene...
The inter-polymer interaction, morphology and molecular motion of the poly(ethylene oxide)/poly(methacrylic acid) (PEO/PMAA) complex were investigated by measuring various nuclear magnetic resonance parameters, such as 13 C chemical shift, 1 HT 1 , 1 HT 1ρ , 1 HT 2 and 13 CT 2 . For the complex, we observed two...
Chemical incorporation of a flexible molecule into a heat-cured epoxy offers an important route by which to toughen the epoxy and tailor its ultimate material properties. Acrylate-terminated urethane (ATU) flexibilizers containing polypropylene glycol have been employed in the present work to modify epoxies composed of a diglycidyl ether of bisphenol-A and bis(4-aminocyclohexyl) methane. Differential...
The adsorption of polyethylene oxide of molecular weight 17 800 and 87 000 at the air/water interface has been studied by neutron reflection and surface tension measurements. Over the concentration range 10 -4 -10 -1 wt% of polymer the surface excesses determined by neutron reflection were consistent with the results derived from the surface tension using the Gibbs equation...
The steady-state fluorescence spectra of poly(N-vinylcarbazole) (PVCz) with various molecular weights in tetrahydrofuran solution were examined. The spectra of PVCz(r) prepared by radical polymerization were almost independent of the molecular weight, while those of PVCz(c) prepared by cationic polymerization were dependent on it. The difference in the temperature dependence of the spectra between...
Permeation fluxes of water and acetic acid from water-acetic acid mixtures were independently monitored as a function of time in differential permeation with dual detection. Two successive permeation waves were detected for water permeation and only one for acetic acid permeation in the transient regime. The onset of the second permeation wave for water coincides with that of acetic acid permeate...
Selectively deuterated liquid crystalline copolyesters of 4,4 -dihydroxy, α,α -dimethylbenzalazine were investigated by proton and deuterium n.m.r. N.m.r. spectra were recorded over a wide temperature range: from 100°C (50 to 60°C below the solid to nematic phase transition, T m ) to 255°C which is well above the isotropic-nematic phase transition. The main-chain liquid crystalline polymer...
Attachment of the peroxide initiator of radical polymerization to the surface of various oxides due to the adsorption of reactive copolymers of peroxide monomer and maleic anhydride (PM-MA) was performed. Plateau adsorption amount of PM-MA depend mainly on the nature of the solvent. It was found that adsorption is irreversible with respect to the solvent. Measuring the exchange between the polymer...
The tensile properties and uniaxial drawing of highly syndiotactic polypropylene (s-PP) have been studied. The results were compared to those of isotactic polypropylene (i-PP) having a comparable molecular weight, molecular-weight distribution and stereoregularity. S-PP and i-PP of different initial morphologies, prepared by crystallization from the melt and solution, were drawn by solid-state coextrusion...
Effects of three different linear styrene-butadiene block copolymers on morphology and selected mechanical properties of high-impact polystyrene/polypropylene blends were investigated. Scanning and transmission electron microscopy and small-angle X-ray scattering were used for the determination of the blend morphology. Impact strength, elongation at break and flexural modulus were measured for further...
Poly(diethylaminoethyl methacrylate-co-hydroxyethyl methacrylate), poly(diethylaminoethyl acrylate-co-hydroxyethyl methacrylate) and poly(methacrylaminopropyl ammonium chloride-co-hydroxyethyl methacrylate) were synthesized by free radical polymerization and characterized using differential scanning calorimetry and dynamic mechanical analysis. Transport of citrate-phosphate-borate buffer solutions...
A thermodynamic model is developed to investigate the extent to which a free polymer, B, can be solubilized into a thin shell layer of grafted A chains of core-shell impact modifier particles. When there is a favourable enthalpy of mixing, free chains of A and B are fully miscible. However, when the A chains are grafted to a surface, only limited amounts of B can be solubilized into this grafted...
The permeability to oxygen of silicone polymer networks with controlled high-molecular-weight side chains was measured using electrochemical techniques. Networks with controlled amounts of pendent chains were prepared by hydrosilation reactions involving the addition of hydrosilanes from crosslinking molecules to the vinyl end-groups of mono- and difunctional prepolymer molecules. Values of the...
In order to obtain the pressure-temperature (P-T) phase diagram of poly(vinylidene fluoride) (PVDF), the melting and crystallization behaviours under high pressure were investigated as a function of temperature and pressure. A corrected P-T phase diagram, in which the triple point (orthorhombic, hexagonal and melt) exists at 320 MPa and 300°C, is proposed. A film mainly consisting of extended-chain...
Divinyl benzene-crosslinked polystyrene supported oximino esters were prepared and developed as a new class of recyclable solid phase acylating reagents. The preparation of these reagents involved a series of polymer analogous reactions starting from styrene-divinyl benzene crosslinked polymer. The introduction of acetyl, benzoyl and p-nitrobenzoyl groups into the polymer system and acylation reaction...
Small-angle neutron scattering (SANS) studies of a 5 vol% mixture of deuterated linear polyethylene with a protonated one was used to investigate the role of partial melting-recrystallization during the solid-state deformation of the polymer in pure shear. The extension of previous studies now gives data that cover the complete deformation range in a continuous manner. The quantity R 0 ,...
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