Patent ID: 8450437

Claim:
A method of polymerizing olefins, comprising: contacting an α-olefin with a catalyst composition under polymerization conditions to form a polymer; wherein the catalyst composition comprises the contact product of an ansa-metallocene, an organoaluminum compound, and an activator, wherein: the ansa-metallocene comprises a compound having the formula: wherein: M 1 is zirconium or hafnium; X′ and X″ are independently F, Cl, Br, or I; E is C or Si; R 1 and R 2 are independently an alkyl group, an aryl group, or hydrogen; R 3A and R 3B are independently a hydrocarbyl group, a trihydrocarbylsilyl group, or hydrogen; n is an integer from 0 to 10, inclusive; R 4A and R 4B are independently a hydrocarbyl group; and the activator comprises an activator-support comprising a solid oxide treated with an electron-withdrawing anion.