Silyl-Terminated Ethylene-co-Norbornene Copolymers by Organotitanium-Based Catalysts

Ethylene (E) and norbornene (N) were copolymerized in the presence of PhSiH3 as chain-transfer agent with [Ti(?5: ?1-C5Me4SiMe2NBu t)(?-Me)2] precatalyst combined with [Ph3C][B(C6F5)4]. The silane was introduced at chain-ends of E-co-N copolymers with concomitant reinitiation of the growing polymer chain. The concentrations of the silane and polymer molecular weight are inversely correlated. The characteristic signals of -SiH2Ph chain-ends were observed by 1H NMR. The Si heteroatom is predominantly adjacent to ethylene units in E-co-N copolymers with high N content.