(621di) Simulation Studies on Et(Flu)(Cp)ZrCl2/MAO Catalyst System for the Synthesis of Syndiotactic Polypropylene

Propylene is one of the most significant compounds whose polymers and copolymers are widely used as commodity thermoplastic, synthetic rubber and elastomers. Initial studies show up that Ziegler-Natta catalyst with transition metals compounds were the first set of catalyst which was used in polymerization. These transition metal derivatives of vanadium and titanium etc. are generally clubbed with co-catalyst which are organometallic compounds like Al(CH₃)₃, Al(C₂H₅)₃, etc. Metallocene catalysts, which were first termed as ferrocene, have enormous potential to be used as a suitable replacement for Ziegler Natta catalyst in various polymer industries. As the polymers prepared by metallocene catalysts are tailored macromolecules whose properties can be accurately designed, it had attracted research intrest from all around the world. Ascribable to single type activation sites of metallocene catalysts, polymers obtained from these have far-flung properties and applications. A typical metallocene catalyst is comprised of cyclopentadienyl [η-C₅H₅:(Cp)]-metal complexes and can be relegated as (i) Symmetrical, classical 'sandwich' structure [(η-C₅H₅)₂M] (ii) Bent or tilted Cp rings with additional ligands L[(η-C₅H₅)₂ML_x] (iiii) Only one Cp ligands with additional ligands, L[(η-C₅H₅)ML_x]. The performance of ethylene(fluorenyl)(cyclopentadienyl)zirconium dichloride catalyst along with methylaluminoxane co-catalyst is studied for the polymerization of propylene in the present work. A comprehensive mathematical model is developed to calculate polymerization rates and polypropylene architectural arguments. In transition metal catalyzed olefin polymerizations, the kinetic parameters are catalyst dependent and therefore their estimation is a crucial step. Evolutionary Differential Evolution optimization algorithm is employed in order to estimate the kinetic parameters of propylene polymerization with the catalyst system under investigation. Further, the effect of polymerization temperature, propylene pressure and cocatalyst to catalyst mole ratio on polymerization rate, number & weight average molecular weights and tacticity of polypropylene is examined.