Patent ID: 8058373

Claim:
A process for continuous solution polymerization of propylene, optionally ethylene, and further optionally one or more C 4-30 Î±-olefins and/or one or more conjugated or nonconjugated dienes under continuous, solution polymerization conditions to prepare a polymer or interpolymer having a M w in the range of from 200,000 to 500,000 g/mol, said process comprising conducting the polymerization in the presence of a catalyst composition comprising a hafnium complex of a polyvalent aryloxyether and a cocatalyst and having a catalyst activity in the range of greater than 0.55 g/Î¼g based on weight of polymer to weight of transition metal; wherein the continuous solution polymerization process operates at a temperature in the range of 120 to 250Â° C., with a propylene concentration in the reactor of 8 percent or less, and a solids content of the reaction mixture of 15 percent or greater and a propylene conversion rate of greater than 85 mole percent; and wherein under operating conditions of the polymerization unreacted monomer or monomers are not separated from the remaining solvent of a reaction mixture prior to recycling of the reaction mixture.