Half-metallocene catalyst compositions and their polymer products

A process for polymerizing olefins in the presence of a catalyst composition, comprising contacting the catalyst composition with at least one olefin monomer and optionally at least one olefin comonomer under polymerization conditions to produce a polymer or copolymer, wherein the catalyst composition comprises a contact product of at least one hybrid metallocene compound and at least one activator,

• wherein the at least one hybrid metallocene compound has the formula:
• wherein:
• M is Zr, Hf, or Ti;
• X1 and X2 independently are a halide or a substituted or unsubstituted aliphatic, aromatic, or cyclic group, or a combination thereof;
• X3 is a substituted or unsubstituted cyclopentadienyl, indenyl, or fluorenyl group, any substituents on X3 independently are a hydrogen atom or a substituted or unsubstituted aliphatic, aromatic, or cyclic group, or a combination thereof;
• X4 is —O—RA, —NH—RA, —PH—RA, —S—RA, or —CRB═NRC,
• wherein:
• RA is an aryl group substituted with at least one alkenyl substituent, any substituents on RA other than the at least one alkenyl substituent independently are a hydrogen atom or a substituted or unsubstituted alkyl, alkenyl, or alkoxy group;
• and
• RB and RC independently are a hydrogen atom or a substituted or unsubstituted aliphatic, aromatic, or cyclic group, or a combination thereof.