Ethylene and alpha olefin trimerization and tandem trimerization/polymerization of ethylene

Mechanistic studies of homogeneous chromium- and titanium- catalyzed trimerization of ethylene will be described. These studies point to a principal pathway for catalyst decompn. for the Fujita titanium system- conproportionation to Ti(III). Accordingly, a silica /MAO supported version has been prepd. and shown to give greater than 10 times higher turnover no. as compared with the homogeneous version under the same conditions. The high activity of the supported Fujita system allows for alpha olefin trimerization to largely two trimers. Tandem and supported- tandem ethylene polymn. and trimerization catalysts yield linear low d. polyethylene from an ethylene-only stock.