Aqueous polymerization of acrylonitrile initiated by the Mn3+/citric acid redox system

Kinetics of polymerization of acrylonitrile initiated by the redox system Mn³⁺/citric acid were investigated in aqueous sulphuric acid in the range of 20–25°; initial rates of polymerization and Mn³⁺ disappearance etc. were measured. The effects of certain water miscible organic solvents and certain cationic and anionic detergents on the rate of polymerization have been examined. A mechanism has been suggested involving formation of a complex between Mn³⁺ and citric acid, decomposition of which yields the initiating free radical and with polymerization being terminated by mutual interaction of growing radicals.