Vinyl polymerization. IV. Co³⁺-tert. butylalcohol red-ox system

Abstract

The effect of tert. butyl alcohol on the polymerization of Methylmethacrylate initiated by cobaltic ions in aqueous perchloric acid medium was tried. Rates of cobaltic ion disappearance and rates of polymerization were measured with variables, [M], [A], [Co³⁺], [H⁺], etc. at constant ionic strength. From the experimental results it was concluded that at low [A], initiation and termination of polymerization was by Co³⁺ species. At higher [A], initiation was still by Co³⁺ species but termination was found to change over to mutual type. At very high [A], Co³⁺ + tert. butyl alcohol reaction was found to function as a red-ox system for polymerization of monomer. An appropriate kinetic scheme was proposed and the various rate constants under different [A] regions evaluated.