(269a) Synthesis of Well-Defined Active Sites in Supported Catalysts Via An Organometallic Approach

This paper will discuss the synthesis of well-defined active sites in supported olefin polymerization catalysts using an organometallic approach. The reaction of B(C6F5)3 with the terminal hydroxyl groups of the silica surface proceeds via water-catalyzed displacement of C6F5H and the formation of supported Lewis acid sites, SiOB(C6F5)2. The resulting solid cocatalyst can be used to activate single-site polymerization catalysts, including Cr(CH2C(CH3)3)4. The design of active sites arises from the predictable nature of the organometallic-surface reactions, which can be demonstrated by a combination of spectroscopic and kinetic probes.