COORDINATION COPOLYMERIZATION OF STYRENE WITH MALEIC ANHYDRIDE BY RARE-EARTH COORDINATION CATALYSTS

摘要

The study on coordination copolymerization of styrene （S） with maleic anhydride （MA） by rare-earth coordination catalysts, NdL₃-Al（i-Bu）₃, has been successfully carried out for the first time. Some features, kinetic behavior, and mechanism of the SMA copolymerization by Nd（naph）₃-Al（i-Bu）₃ system are described and discussed. The copolymex of styrenemaleic anhydride prepared by the NdL₃-Al（i-Bu）₃ systems in benzene at 50℃ is an alternating-rich white powder having high number-average molecular weight of 6—8.5×105. The overall activation energy for the polymerization was found to be 10.5KJ/mol. The polymerization was not suppressed by addition of hydroquinone. The catalytic activity of various ligands in NdL₃ for the copolymerization decreases in the following order: Nd （naph）₃Nd-(P₅₀₇)₃～NdCl₃-6H₂ONd(P₂₀₄)₃Nd（acac）₃. 3H₂O. The experimental results are explained based on a mechanism to be the coordination-type copolymerization in terms of the participation of a monomer-monomer c