Suspension polymerization of vinyl chloride with peroxyester-stannous chloride catalyst system

Abstract

The suspension polymerization of vinyl chloride in the presence of t-butyl peroxyoctoate (t1/2 = 133 hrs) and stannous chloride is effective at 50°C in the absence but not in the presence of acetic acid. The decomposition of the peroxyester in the presence of SnCl2 and acetic acid in the monomer droplet is too rapid for effective polymerization. In the absence of acetic acid, the interaction between the monomer-insoluble SnCl2 and the monomer-soluble peroxyester occurs at the water-monomer interface to generate radicals at a slow rate, presumably by a redox reaction.