Non-ideality in vinyl polymerisation—III: Note on primary radical termination and degradative chain transfer in vinyl acetate polymerisation

Abstract

Preliminary study is reported of the polymerisation of vinyl acetate at two concentrations (5 moles/1 and 2 moles/1) in benzene, initiated by benzoyl peroxide over a wide range of concentrations. From the dependence of rate on initiator concentrations, it is concluded that two different kinetic processes are involved at low and high concentrations of the initiator. The order with respect to initiator varies from about 0.70 to 0.32 on passing to higher concentration range. Mathematical formulations developed earlier for degradative chain transfer are closely followed at low rates of initiation. At higher rates of initiation, the results seem to indicate primary radical termination. It is concluded that both degradative chain transfer (or degradative copolymerisation) and primary radical termination operate in diluted vinyl acetate polymerisation depending on the concentration of initiator.