Substituent Effects of Phenyl Group on Silylene Bridge in Stereospecific Polymerization of Propylene with C₁-Symmetric Ansa-Silylene(fluorenyl)(amido) Dimethyl Titanium Complexes.

ABSTRACT: A C₁-symmetric (methylphenyl)silylene-bridged (fluorenyl)(naphthylamido) titanium complex (1) and (diphenyl)silylene-bridged (fluorenyl)(naphthylamido) titanium complex (2) were synthesized and characterized by ¹H NMR, element analysis, and X-ray crystal analysis. The coordination mode of the fluorenyl ligand to the titanium metal is an η³ manner in each complex. These complexes were applied for propylene polymerization using dried modified methyaluminoxane (dMMAO) as a cocatalyst under different propylene pressures in a semi batch-type method. The catalytic activity was strongly dependent on the structure of the complex and the propylene pressure, where complex 1 exhibited the highest activity (600 kg mol-1·h-1) under a propylene pressure of 8.0 atm to produce high molecular weight polypr

SUBMITTER: Wang H 

PROVIDER: S-EPMC6403971 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature