Polymerization of acrylic acid initiated by a hexavalent chromium-organic sulfur compounds reducing agent system

The kinetics of polymerization of acrylic acid initiated by Cr⁶⁺-thiourea, Cr⁶⁺-thioacetamide, Cr⁶⁺-2-aminoethane thiol, Cr⁶⁺-cysteine, and Cr⁶⁺-thioglycollic acid have been studied at 30, 35, and 40°C in nitrogen. The rates of polymerization were measured. Chromic acid alone did not initiate the polymerization under deaerated and un-deaerated conditions. On the basis of the experimental observation of the dependence of the rate of polymerization R_p on various variables, a suitable kinetic scheme is proposed.