Ethylene and propylene polymerization by bis(indolyl)-coordinated titanium dichlorido complexes activated by modified methylaluminoxane

摘要

Olefin polymerization reactions mediated by diamido-supported titanium complexes are a part of post-metallocene studies. In the present work, dichlorido{di(3-methylindol-2-yl)phenylmethane}titanium (1) and dichlorido{ di(3-methylindol-2-yl)-2-methoxyphenylmethane}titanium (2) were applied for ethylene polymerization. The results showed that the 2/MMAO catalyst system, where MMAO is a modified methylaluminoxane, exhibits ethylene polymerization activity up to 2494 (kg of polyethylene)/(mol of Ti).h.atm. This activity is comparable to the highest known activity in catalyst systems based on diamido-supported titanium complexes. The 2/MMAO system was also active for propylene polymerization (344 (kg of polypropylene)/(mol of Ti).h.atm) to furnish atactic polypropylene.