Vinyl polymerization. IV. Influence of dimethylaniline on solution polymerization of vinyl chloride catalyzed by benzoyl peroxide

In the solution polymerization of vinyl chloride with benzoyl peroxide, it was found that the initial rate of the polymerization was remarkably increased by adding dimethylaniline, but that conversion became constant at lower conversion. It was observed that when the rate became constant the benzoyl peroxide was completely decomposed and the reaction could be reinduced by adding more benzoyl peroxide. On the basis of these results, it seems possible that the polymerization is instituted by the benzoate radical and not by the dimethylaniline radical as suggested by Horner. The benzoate radical is produced through the reaction of dimethylaniline with benzoyl peroxide. In view of such considerations, we postulate a reaction mechanism for the polymerization of vinyl chloride.