A KINETIC-STUDY OF PROPYLENE POLYMERIZATION USING CP2ZRCL METHYLALUMOXANE CATALYSTS/

The kinetics of propylene polymerization using homogeneous Cp2ZrCl2/me thylalumoxane (MAO) catalysts have been investigated at 40 degrees C a nd 1 atm of propylene pressure. The effects of [Al]/[Zr] and [Zr] on t he catalyst activity were studied. It was found that MAO plays a criti cal role in catalyst activation and deactivation. By assuming the coex istence of two dynamic equilibria between active species and inactive ones which are the products of zirconocene dimerization and zirconocen e-MAO complexation, a kinetic model was proposed. The model could sati sfactorily explain most of the experimental results.