C. R. H. I. De Jonge

Oxidations of Organic Compounds Catalyzed by Copper- and Cobalt-Amine Complexes

Selective oxidations of organic substrates catalyzed by transition metal complexes capable of activating oxygen have been of interest since Glaser observed1 more than a hundred years ago that phenylacetylene underwent smooth aerial oxidation to diphenylacetylene when cuprous chloride in ammonia was used as a catalyst. This reaction has since been applied to a wide variety of organic compounds possessing the ethynyl grouping. The Glaser cop-per-amine system has been used in various modifications for many years up to the 1950s when two independant groups found a breakthrough in the oxidation of phenols using a copper-amine complex as a catalyst.2

Automatic equipment for studying the processes of low-temperature dehydrochlorination of chlorine-containing polymers

Abstract A multichannel, highly sensitive installation for the study of the kinetics of decomposition of halogen-containing polymers under automatic conditions has been described. Hydrogen halide produced by polymer decomposition is recorded using mercury-halide ion-selective electrodes, the results being processed by computer. Low-temperature (313–403 K) degradation of poly(vinyl chloride) has been studied. At the glass transition temperature (358 K) the Arrhenius parameters for the degradation of PVC change. A dependence between the segmental mobility of PVC macromolecules and the rate of polymer dehydrochlorination is demonstrated.

Kinetics of high-temperature oxidation of poly(diphenylphenylene oxide)

Abstract Oxidation of poly(2,6-diphenylphenylene oxide) has been studied within the temperature range 380–470°C. The process is autoaccelerated, the maximum rate of oxygen consumption is directly proportional to its pressure. Activation energy changes from 48 kJ/mol below 410° to 110 kJ/mol above 420°. The oxidation rate below 410° depends on the molecular mass of the polymer.

Molecular structure hydrostability and stabilization of polyurethane acetals

Abstract The effect of the nature and ratio of initial comonomers, the method of synthesis, hydrolysis level and the stabilizer type on the molecular-mass parameters of nonisocyanate polyurethane acetals (PUA) has been studied. The nature of active centres of polymerization has been suggested. The course of hydrolytic degradation of various PUAs has been investigated. It has been shown that the hydrostability of PUA can be increased by salt additives.