Late transition metal catalysis for olefin polymerization: New monomers and new materials = Late transition metal catalysis for olefin polymerization: New monomers and new materials

다국어 초록 (Multilingual Abstract)

Molecular transition metal catalysis in synthetic organic reactions has long been studied as the media for production of various organic materials. Late transition metal catalysts for productive olefin polymerization were reported much later (1990’s), but they have advantages in smooth copolymerization of hydrocarbon olefins with functionalized vinyl-compounds. Recent studies on the polyolefin materials with new properties, including environmentally favorable ones. We have studied in the polymerization of new monomers, such as dienes, highly functionalized olefins, strained olefins, and sterically bulky olefins, suited for polymerization catalyzed by the Ni, Fe, Co, and Pd complexes. Homo- and co-polymerization of the new monomers provided the polymer materials, such as aliphatic liquid-crystalline polymers, a component of the physical gels that undergo a sol-gel transition at the definite temperature, highly-ordered polymers having small membered ring, etc. Use of double-decker type bimetallic complexes as the catalysts for the olefin polymerization enabled the reaction at higher temperatures than the reaction using mononuclear catalysts. It is caused by cooperative interaction of the two metal centers to the polymer backbone and its end group, which not only stabilize the polymer end group but enhance selective insertion of monomer molecules into the polymer-metal bond. The complexes have the shorter metal-metal bond than most of the recently reported dinuclear transition metal complexes for olefin polymerization, and their structure supported by the rigid macrocyclic ligands influences the polymerization in a positive fashion.