LiCB(11)(CH(3))(12)-catalyzed radical polymerization of isobutylene: highly branched polyisobutylene and an isobutylene-ethyl acrylate copolymer.

In the presence of LiCB(11)Me(12) catalyst and a nonoxidizing radical initiator, isobutylene undergoes radical chain polymerization in an inert solvent at ambient temperature and pressure to give a new highly branched form of polyisobutylene. Copolymerization with ethyl acrylate is also possible.