KINETIC-STUDY OF PROPYLENE POLYMERIZATION USING ET(H(4)IND)(2)ZRCL2 METHYLALUMOXANE CATALYSTS/

The kinetics of propylene polymerization with Et(H(4)Ind)(2)ZrCl2/meth ylalumoxane (MAO) catalysts have been investigated at 0-50 degrees C a nd 1 atm of propylene pressure. The effects of polymerization temperat ure, catalyst concentration, and catalyst/cocatalyst mole ratio on the catalyst activity and on the properties of the polypropylene products were studied. By assuming the coexistence of two dynamic equilibria b etween catalytically active species and two inactive species, which ar e the products of zirconocene dimerization and excessive zirconocene-M AO complexation, a kinetic model has been developed. This model could satisfactorily explain most of experimental results.