Syndiospecific Polymerization of Styrene Using a Heterogeneous Titanocene Catalyst
A. Entezami*, M. Agaalipour and P. Najafi Moghaddam
Polymer Chemistry Laboratory, Department of Chemistry, Tabriz University,
A supported-catalyst system for the polymerization of styrene was prepared by the immobilization of pre-activated indenyl titanium trichloride (IndTiCl3) with methylaluminoxane (MAO) on silica. This catalyst showed a higher productivity using a smaller amount of metallocene on the catalyst support. Other polymerization conditions that affect the productivity of the catalyst, including the ratio of Ti/SiO2 (wt%) and Al/Ti, and the time for polymerization, were also investigated. The polymers obtained from this system were extracted using methylethyl ketone and the syndiotacticity was calculated from the weight of the remaining insoluble polymer. With these optimized conditions, and the use of a heterogeneous catalyst, we developed a more efficient catalyst system that is more suitable for industrial applications than previously developed systems.
Keywords: Half-sandwich titanocene, Syndiotactic polystyrene, Styrene polymerization, Metallocene silica-supported titanocene