Abstract
This is a review on the antioxidant action of transition metal dialkyldithiophosphates and dialkyldithiocarbamates in autoxidation of hydrocarbon. These complexes interrupt autoxidation by trapping chain-propagating peroxy radicals and by decomposition of hydroperoxides into non-radical products. Trapping peroxy radicals occurs at sulphur atom or at central metal atom of these complexes. Hydroperoxide decomposition proceeds in three stages, i. e. a fast homolytic decomposition followed by an induction period, and a fast heterolytic decomposition. In the first or the second stage, these complexes change into ionic catalysts which are responsible for the heterolytic decomposition of the third stage. The kinetics, the products and the mechanisms of inhibition by these complexes are summarized.
