Catalytic Production of Olefin Block Copolymers via Chain Shuttling Polymerization

作者：Daniel J. Arriola, Edmund M. Carnahan, Phillip D. Hustad, Roger L. Kuhlman, Timothy T. Wenzel · 发表于：Science · 年份：2006 · DOI：10.1126/science.1125268 · 被引用次数：1001 · 研究领域：Organometallic Complex Synthesis and Catalysis、Advanced Polymer Synthesis and Characterization、Synthetic Organic Chemistry Methods

We report a catalytic system that produces olefin block copolymers with alternating semicrystalline and amorphous segments, achieved by varying the ratio of alpha-olefin to ethylene in the two types of blocks. The system uses a chain shuttling agent to transfer growing chains between two distinct catalysts with different monomer selectivities in a single polymerization reactor. The block copolymers simultaneously have high melting temperatures and low glass transition temperatures, and therefore they maintain excellent elastomeric properties at high temperatures. Furthermore, the materials are effectively produced in economically favorable, continuous polymerization processes.