Polymerization of conjugated dienes with a homogeneous Ziegler–Natta catalytic system based on a carbon-bridged bis(phenolate) yttrium alkyl complex

Abstract

A novel carbon-bridged bis(phenolate) yttrium alkyl complex [(EDBP)Y(CH₂SiMe₃)(THF)₃] (1) was synthesized by a reaction of 2,2′-ethylidene-bis(4,6-di-tert-butyl-phenol) (EDBPH₂) and Y(CH₂SiMe₃)₃. The structure of complex 1 was determined by X-ray crystallography. Homo- and copolymerization of isoprene and 1,3-butadiene was carried out and catalyzed by the 1/MAO/triisobutylaluminum (TIBA) system. The effects of TIBA/MAO and the total [Al]/[1] molar ratio on the activity and regioselectivity of polymerization, kinetics and controllable characteristics of the polymerization system were also investigated.