Patent ID: 7514509
Filing Date: 2009-04-07
Classification: B01J,C08F

Abstract:
1. An olefin polymerization process comprising: introducing propylene monomer to a reaction zone; disposing an isospecific metallocene catalyst within the reaction zone, wherein the isospecific metallocene catalyst has the formula: wherein Si is silicon and is a structural bridge between Cp and Flu, Cp is a cyclopentadienyl group, Flu is a fluorenyl group, M is a transition metal, A is a leaving group, n is an integer equal to the valence of M minus 2, R A is independently selected from alkyls, R B is independently selected from hydrogen, alkyls or combinations thereof and, wherein one R B is a tert-butyl in the 3 position, and R C is independently selected from hydrogen, alkyls, aromatics or combinations thereof, and wherein the Flu is substituted at the 3 and the 6 positions each with a tert-butyl, and at the 2 and the 7 positions; contacting the propylene monomer with the isospecific metallocene catalyst to form isotactic polypropylene; and recovering the isotactic polypropylene from the reaction zone.