title: A sterically expanded "constrained geometry catalyst" for highly active olefin polymerization and copolymerization: an unyielding comonomer effect.
abstract: The 14 A octamethyloctahydrodibenzofluorene moiety has been incorporated into a sterically expanded constrained geometry catalyst, Me2Si(eta1-C29H36)(eta1-N-tBu)ZrCl2.OEt2 (1). The solid-state structure suggests that the activated olefin polymerization catalyst is quite spatially accessible, rationalizing its extraordinary reactivity toward alpha-olefins. 1/MAO (MAO = methylaluminoxane) can be more reactive toward alpha-olefins than toward ethylene and exhibit activities that are linearly and continuously proportional to 4-methyl-1-pentene or 1-octene concentration in their copolymerizations with ethylene.
authors.affiliation: Department of Chemistry, Texas A&M University, College Station, TX 77843-3255, USA.
authors.forename: Levi J
authors.initials: LJ
authors.lastname: Irwin
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Reibenspies
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Miller