exo-methylene-functionalized polyethylenes via ring-opening ziegler polymerization. Product control in organolanthanide-catalyzed methylenecyclopropane polymerization/copolymerization

The authors report on the efforts to broaden the scope of the particular polymerization process using highly reactive, efficiently prepared methylenecyclopropane and organolanthanide catalysts of the type (Cp′₂LnH)₂ (Cp′ = η⁵-Me₅C₅; Ln = lanthanide), the activities of which can be significantly varied with the Ln³⁺ ionic radius. Results represent an attractive elaboration of the scope of exo-methylenecycloalkane ring-opening Ziegler polymerization. Both a more readily available and reactive monomer as well as tunable organo-f-element are shown to be compatible with such routes to exo-methylene-functionalized polyolefins.