Kinetic Study on the Oxidation of 2, 4-Dimethylpentane

Abstract

The kinetics of the oxidation of 2, 4Tdimethylpentane, a model compound of polypropylene, were studied at 70° C with azobisisobutyronitrile as an initiator. The kinetic order of the rate of oxidation on the substrate concentration was 0.76. This low kinetic dependence was interpreted by the contribution of intramolecular propagation. The ratio of the rate constants of intramolecular propagation to intermolecular propagation was estimated as about 100, which was in reasonable agreement with the literature value determined by product analyses. The kinetic order increased in the presence of added t-butyl hydroperoxide. It was suggested that kinetic study may be useful in elucidating the importance of intramolecular propagation in the oxidation of polypropylene, where the product analysis is quite difficult.