Showing papers in "European Polymer Journal in 1969"

TL;DR: In this article, a model for the non-Newtonian viscous behavior of polymer melts has been proposed; it is based on the mol. wt. distribution and an approximation to the behaviour of a monodisperse polymer.

TL;DR: In this paper, the authors measured the dilute solution properties of Union Carbide polysulphone by light scattering, osmometry, and viscometry; Mark-Houwink expressions have been determined in a thermodynamically good solvent, two thermodynamic bad solvents, and one solvent at the θ-temperature.

TL;DR: In this paper, it was shown that the radical recombination reaction can be neglected and it is not yet clear whether the propagation step involves the reaction of radicals with adsorbed monomer or with monomer diffusing to the electrode from the gas phase.

TL;DR: In this paper, it was shown that cetyl vinyl ether has two different solid crystalline states with a phase transition point at −16° and −2·5°.

TL;DR: In this article, a unimolecular elimination mechanism is formulated for the thermal dehydrochlorination of PVC in an inert atmosphere between 160° and 200° and at low extents of deodorization.

TL;DR: In this paper, the authors used osmotic, light scattering and viscometric techniques at 25° to examine ten fractions of a bisphenol A polycarbonate (Ma 7000-77,000).

TL;DR: In this paper, the authors measured the viscosity and sedimentation properties of amylose in a thermodynamically ideal solvent (0·33 M KCl) and a good solvent ( 0·2 M KOH) and found that the divergence of the exponents from a value of 0·50 for the measurements in KOH is due to expansion of the molecule through solvent-polymer interaction rather than to partial free-draining character.

TL;DR: In this article, the authors discuss the polymerisation of l'acide acrylique liquide and cristallise sous l'action des rayons gamma. But they do not discuss the effect of different additifs on the reaction.

TL;DR: In this article, the kinetics of the overall process of the thermal degradation of dissolved poly(vinyl chloride), taking place under oxygen-free conditions, have been studied, and the kinetic treatment of the process has been accomplished, based on the assumption of special polymer sequences.

TL;DR: In this paper, cyclo-olefins are polymerized under very mild conditions to give linear polymers using a mixture of WCl 6 and AlBr 3, which contain no vinylic unsaturation.

TL;DR: In this paper, the authors discuss the importance of polymeres syndiotactiques in terms of their role in the production of acides acryliques in the field of chemical engineering.

TL;DR: The triclinic structure of trans poly octenamer and trans polydecenamer has been checked by a three-dimensional Fourier analysis as mentioned in this paper, where the α and b axes of the monoclinic unit cells have the same value for all the trans polyalkenamers examined.

TL;DR: In this article, the authors made measurements between 10 2 and 10 10 Hz on samples of polyethylene glycol 200 polyurethane, polypropylene glycol polyurethsane and polyethylen glycol 450 polyurentane elastomers and found that they exhibit low dielectric permittivity and loss factor at temperatures below a transition temperature measured by differential scanning calorimetry, which is best explained by the existence of Maxwell-Wagner two-phase interfacial polarization.

TL;DR: Propylene sulphide is polymerized by zinc and cadmium thiolates, the latter being particularly active initiators as discussed by the authors, and there is a period of accelerating rate after which the rates are first order in monomer and initiator.

TL;DR: The first two products of condensation of ϱ-di(chloromethyl) benzene with benzene (I) in the presence of SnCl4 are benzyl chloromethsyl benzene(II) and dibenzyl benzenes (III) as mentioned in this paper.

TL;DR: In this paper, a report on the polymerization of 1,3-pentadiene by cobalt catalysts prepared from AlEt 2 Cl, Al 2 Et 3 Cl 3 or alkyl aluminum compounds containing AlOAl bonds is given.

TL;DR: In this article, the authors studied the kinetics of anionic polymerization of α-methylstyrene in tetrahydropyran dilatometrically over the temperature range −20 to 9°.

TL;DR: In this article, the thermal stability of saturated polyvinylchloride models was found not to be greatly affected by the length of the chain, but to diminish rapidly if the number of double bonds in the molecule rises.

TL;DR: In this paper, a comparison between the Arrhenius plots for eleven different propagation rate constants for the anionic polymerization of α-methylstyrene was made in terms of propagation by contact ion-pairs and the more reactive solvent-separated ion-pair.

TL;DR: In this article, the acid-catalysed decomposition of trimethylol melamine (TMM), hexamethylolmelamine (HMM), HMM-Me, TMM-TMM, and hexamethoxymethyl melamine was investigated kinetically.

TL;DR: In this paper, the kinetics of anionic polymerization of styrene in tetrahydropyran have been studied dilatometrically, the concentration of living ends being determined spectrophotometrinically.

TL;DR: The absorption spectra of living anionic oligomers of α-methylstyrene with lithium, sodium and potassium counterions have been recorded at temperatures down to −100° in tetrahydrofuran (THF) and −50° in triethylamine triphosphate (THP) as discussed by the authors.

TL;DR: In this paper, a highly branched, globular structure for both the soluble and insoluble polymers is proposed based on the results of oxidative and thermal degradation, and the mechanism of the process by which the insoluble polymer is formed is discussed.

TL;DR: In this paper, the effects of chain length of diols and aliphatic dicarboxylic acids on the rate of polyesterification were studied and it was shown that the reaction rate is only slightly influenced by the chain-length of the acid.

TL;DR: In this article, the composition heterogeneity of the products of polymer-analogous reactions was investigated using Monte-Carlo simulation, and it was shown that the degree of heterogeneity passes through a maximum, in most cases at 50 per cent conversion.

TL;DR: In this paper, the effect of the first and second dissociation constants of a dicarboxylic acid on polyesterification reactions with diols has been justified by model tests.

TL;DR: In this article, the applicability of different theories which have been put forward for the determination of K (measure of the unperturbed dimensions) is discussed, and the stiffness of the chain has been discussed in the light of steric factor σ and Ptitsyn Eizner parameter λ.