Process for using metallocene catalyst in a continuous reactor system

The present invention provides a composition and a process wherein a metallocene catalyst is dissolved in an alumoxane which has been dissolved in a solvent to form a concentrated stock solution of metallocene-alumoxane which can be stored for at least 14 days. The metallocene-alumoxane solution is stored under an oxygen- and water-free environment and more preferably under argon at temperatures that can range from about 25 degrees Fahrenheit (-4 degrees C.) to about 85 degrees Fahrenheit (29 degrees C.). Before or at the time that the metallocene-alumoxane solution is injected into the reactor, it is diluted with a second solution comprised of either an alumoxane, an aluminum alkyl or mixtures thereof dissolved in an oleaginous solvent. The addition of the aluminum based co-catalyst serves a two fold purpose. First, it provides the aluminum necessary to enhance the catalytic reaction and second, the aluminum to metal atomic or mole ratio can be easily optimized by adjusting the amount of the second solution to establish an optimal catalyst efficiency. The second solution either can be added to the concentrated metallocene-alumoxane solution as a side stream into the reactor or can be added directly to the metallocene-alumoxane solution prior to the time that the metallocene-alumoxane solution is injected into the reactor. The metallocenes employed in the process are organometallic compounds which are cyclopentadienyl derivatives of a Group 4b, 5b, 6b, or 8 metal of the Periodic Table and include mono, di and tricyclopentadienyls and their derivatives of the transition metals.