The mechanism and kinetics of the heterogeneous polymerization of vinyl monomers II. The benzoyl peroxide catalyzed polymerization of vinylidene chloride

Abstract

The polymerization of vinylidene chloride initiated with from 0.02 to 1.0 mol. % benzoyl peroxide has been studied at temperatures from 47 to 75° C. In all cases the rate of polymerization was found to increase throughout the first 30% polymerization. The reaction rate when compared at equal extents of conversion was found to vary as the square root of the benzoyl peroxide concentration. In the presence of tetrahydrofuran the rate of polymerization remained constant during the early stages of the reaction. These results can be explained by the mechanism put forward in part I, namely, that active centres undergo transfer reactions with ‘dead’ polymer resulting in the formation of immobile polymer centres which continue to grow and are finally terminated by chain transfer reactions with monomer.