Metal thiolates as initiators for the polymerisation of alkylene sulphides

Abstract

Thiolates of the general formula (XCH₂·CH₂·S)_yM, where M = Zn or Cd, y= 1 or 2, and X is a group capable of co-ordinating to M, are efficient initiators of the polymerisation of episulphides (less so where M = Cu or Ag). These compounds are often soluble in the reaction system and in all cases the cadmium derivatives are the most effective. although they are less distinct compounds than the zinc analogues. Variation of the nature of X allows the reproducible preparation of polymers bearing a variety of end-groups.