Polymerisation by the chromate/arsenite system

Abstract

The aqueous polymerisation of methyl methacrylate initiated by the chromate/arsenite system has been studied. It is observed that the polymerisation by the above redox system is catalysed by OH^θ though the parent reaction between chromate and arsenite is catalysed by H^⊕. It is also observed that traces of Cu^2⊕ inhibit both the polymerization reaction as also the parent reaction. From these observations it is concluded (1) intermediate valency states of chromium has no initiating power in alkali solution and (2) the redox reaction between chromate and arsenite is a chain reaction involving single electron transfer and the intermediate As^4⊕ thus produced is the initiating species.