Controlled radical polymerisation of methyl acrylate initiated by a well-defined cobalt alkyl complex.

Cobalt-mediated radical polymerisation of methyl acrylate is effected at moderate temperature by both a square planar bis(beta-ketoaminato)cobalt(II) complex in the presence of V-70 diazo radical initiator, and by a well-defined cobalt(III) alkyl derivative in the absence of a diazo complex. Polymerisation rates suggest that both reversible termination and degenerative transfer mechanisms are operative.