THE ROLE OF QUINONE METHIDES IN THERMOSTABILIZATION OF HYDROCARBON POLYMERS .2. PROPERTIES AND ACTIVITY MECHANISMS

Retardation of thermal oxidation by quinone methides (QM) was observed in model experiments with liquid hydrocarbons. The retardative effect decreases with increasing temperature. Long-term heat ageing of polyp ropylene is more efficiently reduced by phenolic antioxidants prone to form the corresponding QM in situ. Potential mechanistic features inv olving reactivity of QM with free radicals, hydroperoxide decomposing antioxidants and hindered amines are reviewed from the point of view o f thermal processes in polyolefins. (C) 1996 Elsevier Science Limited