Patent ID: 6388027
Filing Date: 2002-05-14
Classification: C08F,Y10S

Abstract:
A process for transitioning from a first sticky polymer to a second sticky polymer in a gas phase fluidized bed polymerization, which process comprises the steps of:(a) terminating the feed of catalyst to a reactor, thereby allowing reaction rate to decrease; (b) terminating the polymerization using a reversible catalyst kill agent; (c) passivating the polymer with a gel inhibitor; (d) stopping polymer transfer from the reactor to post-reaction purging and polishing equipment, thereby recovering aim-grade product from the post reaction equipment; (e) flow and pressure purging to remove kill agent; (f) feeding cocatalyst and optional promoters to the reactor to establish concentrations of these components; (g) establishing reaction conditions for the second sticky polymer; (h) re-initiating catalyst feed; and (i) feeding fluidization aid and optional diene to the reactor.