Polypropylene intramolecular decomposition

Tsuchlya and Suml (6) have thermally degraded polypropylene in the temperature range ShO-AOO C and have made a detailed analysis of all products with 1-12 carbon atoms. On this basis, a decomposition mechanism has been proposed. Initiation occurs by random scission of the main chain. The radicals thus formed undergo transfer reactions most readily at tertiary carbon atoms but the distribution of products indicates that intramolecular transfer to both third and fourth carbon atoms is particularly important. 

The product study272) and the kinetic study261) form the experimental basis for the discussion of complex transformations of thiobisphenolic antioxidants. Their retardation effect in polypropylene after the induction period and the mechanism of formation of intermediates or products catalytically active in ROOH decomposition indicate the reactivity of both different centres in molecule and provide partial data for the discussion of intramolecular synergism of thiobisphenols5 57,258,26 ). 

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