Polymerization of acrylonitrile by V5+–lactic acid system in aqueous sulfuric acid

Abstract Kinetics of polymerization of acrylonitrile by the redox system V5+–lactic acid in sulfuric acid at 20–35°C was studied. Oxidation of lactic acid by V5+ in the absence of monomer was also carried out under identical conditions. The rates of polymerization, V5+ disappearance and the chainlengths of polyacrylonitrile were measured. From the results it is concluded that the polymerization reaction is initiated by an organic free radical arising from the V5+–lactic acid reaction with termination by V5+ ions. Mutual termination of active polymer radicals does not appear to operate under the conditions studied. The various rate parameters were evaluated.