Bimodal Cyclic Olefin Copolymers Prepared by a Half‐Zirconocene Catalyst

By employing a structurally distinctive six‐coordinated half‐zirconocene catalyst, cyclic olefin copolymers with bimodal molecular weight distribution have been synthesized by utilizing a single catalyst system in one pot. The molecular weight distribution has been found to be tunable via adjustment of the monomer feed ratio. This work also constitutes the inaugural application of a half‐metallocene catalyst bearing only one chloride ligand for the preparation of cyclic olefin copolymers; additionally, the catalyst exhibits markedly high activity in the copolymerization of ethylene and norbornene. Structural characterization of the obtained COCs enables a mechanistic analysis of the copolymerization, revealing that the catalyst's unique asymmetric configuration is the fundamental origin of the observed bimodal distribution, thereby laying a rational foundation for future catalyst design.