Method for Controlling Bimodal Catalyst Activity During Polymerization

摘要

A method of performing a polymerization reaction in a gas phase polymerization reactor to produce a bimodal polymer while controlling activity of a bimodal polymerization catalyst composition in the reactor by controlling concentration of at least one induced condensing agent (‘ICA’) in the reactor is provided. In some embodiments, the ICA is isopentane (or another hydrocarbon compound) and the bimodal catalyst composition includes a Group 15 and metal containing catalyst compound (or other HMW catalyst for catalyzing polymerization of a high molecular weight fraction of the product), and a metallocene catalyst compound (or other LMW catalyst for catalyzing polymerization of a low molecular weight fraction of the product).