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The viscosity and elution behaviour of polystyrene sulfonate ionomers with varying ionic content has been studied in the pure solvents chloroform (CHL), tetrahydrofuran (THF), dioxan (DIO), ethyl acetate (EA) and dimethylformamide (DMF) as well as in their cononsolvent mixtures CHL/THF (50:50), DIO/CHL (75:25) and in the cosolvent mixture EA/DMF (50:50). In the pure solvents with low dielectric constant...
Novel types of fumaramate bearing a phosphorylcholine group, alkyl-2-[2′-(trimethylammonium)ethyl phosphoryl]ethyl fumaramate [alkyl = isopropyl (IPTPFA) and methyl (MTPFA)] were synthesized. IPTPFA and MTPFA were polymerized and copolymerized with methyl methacrylate (MMA) in the presence of radical initiators. Critical micelle concentrations (CMC) of IPTPFA and MTPFA were 1.7 × 10 −3 and...
The permeability of a functionalized dye solute in various amorphous polymers above the glass transition temperature has been investigated using dye diffusion thermal transfer printing. A disazothiophene dye molecule was transferred from a constant dye-donor polymer matrix to a variety of dye-acceptor polymer matrices. All dye-acceptor polymers were amorphous, but their chemical structures, glass...
Amorphous poly(nonamethylene thiourea) (polythiourea 9) ((CH 2 ) 9 NHCSNH) n , under an electric field was examined below the glass transition temperature (T g = 48°C) by X-rays. First, a structural change on poling was observed; the average inter-chain distance in the direction of the electric field increased by 0.3%, suggesting the parallel alignment of dipoles of...
Graft copolymers of functionalized polyethylene having free car☐ylic groups/PEox/ and liquid crystalline polyester SBH derived from sebacic acid, 4,4′-dihydroxybiphenyl and 4-hydroxybenzoic acid, prepared in various conditions, as well as fractionation products of the graft copolymers, were investigated by infra-red spectroscopy. The grafting has been followed by changes in the amount of car☐ylic...
A charge-transfer fluorescence molecule has been applied to study the structure of polystyrene latices and polystyrene—glycidylmethacrylate core—shell latices. Information on the composition of the latex could be obtained on the basis of the combined application of steady state and time-resolved fluorescence measurements. Time-resolved measurements were done using a frequency-domain approach; the...
The gel point of a dicyanate ester resin (Arocy B-10 (4-4′-dicyanato-2,2′-diphenylpropane)) heated following irradiation in the presence of the catalyst tricarbonyl cyclopentadienyl manganese (CpMn(CO) 3 ) was studied using differential scanning calorimetry (d.s.c.) and dynamic rheological techniques over the temperature range 110–140°C. The gel times of another commercial cyanate ester (RTX366)...
Several samples of cellulose acetate polymers with varying degrees of substitution (DS) between 0.7 and 1.7 have been prepared and tested for their biodegradation potential. The original and biodegraded polymers were characterized using chemical techniques as well as nuclear magnetic resonance, Fourier transform infra-red spectroscopy, gel permeation chromatography, solution viscosity and X-ray diffraction...
Chemical oxidative polymerization of dodecylbenzenesulfonic acid aniline salt in water using ammonium peroxydisulfate as oxidant was found to give an homogeneous polyaniline suspension. An aqueous transparent and green uniform suspension containing polyaniline complexed and doped with dodecylbenzenesulfonic acid was obtained to show a typical emeraldine salt spectrum. The polyaniline suspension was...
Evolution of structural gradients developed in injection moulded polyethylene naphthalate was studied using a variety of structural techniques including a newly developed micro-beam X-ray diffraction pole figure technique. PEN, being a slowly crystallizing high temperature polymer, forms a three layer structure: amorphous skin + shear crystallized intermediate layer + amorphous core in the interior...
For the purpose of obtaining modified poly(vinyl alcohol-co-vinyl acetate), or partially hydrolysed poly(vinyl alcohol) (PVAL), containing sodium car☐ylate groups, -COONa, in polymer chains, ten car☐ylic monomers have been investigated for copolymerization with vinyl acetate, and the PVALs obtained by alcoholysis have been compared with each other. Dibasic acidic monomers, itaconic, fumaric and maleic...
Conformational properties of ethylene glycol, oligo-, and poly(ethylene oxide) ranging in weight-average molecular weight (M w ) from 62 to 1.1 × 10 7 have been studied by static light scattering and viscometry in salt-free and 0.45 M K 2 SO 4 water and in benzene. Above M w = 6 × 10 3 , intrinsic viscosity ([η]) and z-average square radius of gyration...
Small-angle neutron scattering has recently been applied to study liquid-liquid phase separation in blends of branched and linear polyethylenes. While experimental results from two groups are basically the same, interpretations differ strongly. The analyses of Schipp . (Polymer, 1996, 37, 2291), which favour phase separation, are shown to be incorrect. There is no contraction of chain dimensions in...
Macroscopic structures have been created in poly(γ-benzyl-l-glutamate) films, OM-20 films, poly(hexyl-isocyanate) films and 4′-pentyl-4-cyanobiphenyl using spin-coating equipment with rotating cap. The orientation of the molecules in the films has been determined using crossed polarizers. The visible macroscopic maltese crosses were the result of a radial symmetrical orientation of the molecules in...
A bilayer specimen composed of a thin polystyrene (PS) film on a polycarbonate (PC) mini-bar was prepared for tensile test. It was observed by scanning electron microscopy that periodic cracks appeared in the PS film when the specimen was deformed in tension. From the maximum crack spacing in the PS, the ultimate shear stress at the PS/PC interface was estimated to be 49 MPa using the periodic cracking...
The cure behaviour of the ethyl ester derivatives of 4,4′-oxydianiline (ODA)/pyromellitic dianhydride (PMDA) poly(amic acid) to the corresponding imide was investigated using isothermal and dynamic mass spectroscopy, FT-Raman spectroscopy and density gradient column analysis. Both the rate cure and per cent conversion were dependent on the isomer composition, occurring in the order para >meta >...
We report here the synthesis and characterization of poly(amic ethyl ester) oligomers functionalized with trimethoxysilyl end-groups. The oligomers were prepared via the condensation of 1,1-bis(4-aminophenyl)-1-phenyl-2.2,2-trifluoroethane, diethyldichloromellitate and p-aminophenyltrimethoxysilane. The p-amino-phenyltrimethoxysilane was used to control both molecular weight and end-group functionality...
In epoxy-amine kinetic studies, the determination of the ratio of rate constants, (R) for hydrogens on primary and secondary amine groups is very important; in fact R is related to the network morphology. In this paper we show that R can be directly calculated from the ratio of the concentrations of primary to secondary amine at (d[A 2 ]/dt) max , d[A 2 ]/dt being the reaction...
A new three-dimensional hyperbranched polymer with 4-(2-cyano-2-methoxy-carbonylvinyl)aniline as a second-order nonlinear optical chromophore has been synthesized starting from 4-formyl-N,N-di(2-hydroxyethyl)aniline and cyanoacetic acid by a one-pot Knoevenagel polycondensation using 4-(dimethylamino)pyridine as a base. This hyperbranched polymer with a good solubility in polar organic solvents, such...
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