TRANSITION-METAL-CATALYZED CATIONIC POLYMERIZATIONS

Certain complexes of platinum, rhodium, iridium and cobalt are capable of initiating cationic vinyl and ring-opening polymerizations in the presence of a Si-H containing cocatalyst. An investigation has shown t hat two distinctly different mechanisms are involved, however, in both cases cationic polymerization can be explained by the formal attack o f an electrophilic silicon species on the monomers. Since the transiti on metal complexes listed above also are catalysts for hydrosilation r eactions, it is possible to carry out simultaneous cationic polymeriza tions and hydrosilation reactions to prepare novel and interesting pol ymers and oligomers.