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Oxidation of atactic polypropylene (PPH) has been used in the preparation and characterization of hydroperoxide PPOOH, from which radicals PPOO- were generated. Their interaction with 2,6-ditert-butyl-4-methylphenol (BHT) demonstrated transformations of the antioxidant, leading, on the one hand, to peroxycyclohexadienone, PPOO-CHD, in which the residue of reacted BHT is bound on PPOO and, on the other, to compounds resulting from the oxidative coupling of BHT; of these, 4,4′-ethylenebis (2,6-ditert-butylphenol) and 3,3′,5,5′-tetratert-butylstilbenequinone were identified. Further products of coupling are light- to deep- brown; some of them contain phenolic and quinomethinoidic functions. PPOO-CHD may take an active part in the atmospheric ageing of PPH arising from decomposition caused by heat, radiation or catalytic impurities.

The solid-, cholesteric- and liquid-state polymerizations of cholesteryl-vinyl-succinate (CVS) are studied. Only one of the three polymorphic modifications of CVS oligomerizes in the solid state into oligomers of degree P = 2 to 6 in a homogeneous topochemical reaction. The rate of polymerization in the cholesteric state is lower than that in the liquid state at the same temperature. Kinetic constants were measured at 85° using benzoyl peroxide as initiator and the Banfield radical, giving Eoverall = 15.4, 36.4 kcal/mole−1; f = 0.52, 0.19; k p /k t 1 2 = 0.0167, 0.0192 , (1/mole sec) 1 2 , ( E p − 1 2 E t ) = 0.40, 21.4 kcal mole−1. The values refer to the liquid- and the cholesteric-state reactions, respectively. The average degree of polymerization is low in both cases ( P = 20 and 22 ). It was concluded that the molecular weights are controlled by chain transfer and that the initiation reaction is mostly dependent on the phase where the reaction takes place.