Development of single-site new olefin polymerization catalyst systems using MgCl2-based activators:: MAO-free MgCl2-supported FI catalyst systems

MAO-free new single-site catalyst systems have been developed for olefin polymerization, which are comprised of bis(phenoxy-imine) Ti, Zr, or V complexes (Ti-, Zr-, or V-FI Catalysts) and MgCl2-based compounds. These new catalyst combinations are highly active sin le-site (Ti-FI Catalysts), exceptionally active (Zr-FI Catalysts), or highly active, thermally robust. single-site (V-FI Catalyst) catalysts for ethylene polymerization. The catalysts can display higher catalytic performance (i.e.. catalytic activity, stereoselectivity, thermal stability) than those activated by the well-established MAO activators. In addition, these catalysts are supported, and thus possess a technological advantage vis-a-vis control over polymer morphology, which is essential for commercial application. Therefore, the application of MgCl2-based compounds capable of working both as an activator and a support for non-metallocene complexes provides a conceptually new strategy for the development of high-performance supported single-site catalysts.