Patent ID: 7799877

Claim:
A method of olefin polymerization in a continuous reactor, the method comprising: (a) determining feed rates F H2 and F M of hydrogen and a selected monomer or comonomer, respectively, provided to the reactor and gas phase relative concentrations C H2 and C M of the hydrogen and the selected monomer or comonomer, respectively, in a recycle gas stream of the reactor to obtain a leading indicator function L defined by: L = C H ⁢ ⁢ 2 F H ⁢ ⁢ 2 C M F M ; (b) comparing L or L −1 to a target value; and (c) adjusting at least one reactor parameter in response to a deviation between L or L −1 and the target value; wherein the olefin polymerization is catalyzed by a catalyst system, the catalyst system comprising a metallocene catalyst and a non-metallocene catalyst; and wherein the step of adjusting at least one reactor parameter is effective to alter the relative productivity of the catalysts.