Supported Organometallic Catalysts for Olefin Polymerization

The concept of the basic role of the transition metal-carbon bond in the catalytic polymerization of olefins was formulated in the early stages of the study of Ziegler-Natta catalysts (see Ref. 1). In this connection, attempts to use the individual organometallic transition metal compounds as catalysts for olefin polymerization have been made regularly when such compounds were synthesized[2-10]. Polymerization of ethylene in the presence of organometallic compounds containing -CH₃[2, 3], -C₆H₅[7], -CH₂C₆H₅[5, 6], -C₃H₅[4, 10], -CH₂-C(CH₃)₃[10], and -CH₂-Si(CH₃)₃[10] as organic ligands have been reported. In some cases such compounds were considered to be “models of the active centers.” However, considering the experimental results from this point of view led to a discrepancy with the following observations: