Non-Metallocene Organolanthanide Polymerization Catalysis

Non-metallocene rare-earth metal (or lanthanide, Ln) alkyl complexes have emerged as versatile catalysts for the (stereoregular) homo- and copolymerization of industrially relevant monomers including ethylene, butadiene, styrene, and methyl methacrylate, with the polymerization performance being highly dependent on the Ln metal size, stabilizing ancillary ligand, type of co-catalyst, and additives. The long-term goal of the project is to develop efficient synthesis procedures for lanthanide bis(alkyl) co mplexes bearing tailor-made cyclopentadienyl, amido, and alkoxo ligands. The application of tailor-made stabilizing ligand backbones is crucial for (i) facilitating stereospecific polymerization, (ii) facilitating copolymerization, and (iii) understandin g the action of co-catalysts (e.g., borate reagents) as well as additives (e.g., organoaluminum compounds). Main emphasis will be put on studying the polymerization performance of the bis(alkyl) complexes in order to compile a postlanthanidocene library categorizing stereospecificity and copolymerization behavior. The successful development of such single-component catalysts will involve comprehensive structural investigations and (predictive) computational studies. Finally, consideration is given to t he in situ generation of active catalysts (drop-in-catalysts) addressing easy handling and manipulation under industrially relevant conditions.