Abstract: The present disclosure provides a method for improving the activity of Ziegler-Natta (ZN) catalysts. The method includes forming a modified precursor composition of a ZN catalyst by providing a precursor composition of the ZN catalyst for treatment with an aluminum alkyl compound in a liquid organic solvent. The precursor composition of the ZN catalyst includes at least one titanium compound. The at least one titanium compound in the precursor composition is treated with the aluminum alkyl compound in the liquid organic solvent, where the aluminum alkyl compound converts the at least one titanium compound in the precursor composition into a modified state of the ZN catalyst. At least a portion of the aluminum alkyl compound not consumed in converting the at least one titanium compound in the precursor composition into the modified state of the ZN catalyst and reaction by-product compounds in the liquid organic solvent are removed to form the modified precursor composition of the ZN catalyst.

Abstract: The present invention provides a metallocene complex capable of producing a homopolypropylene having a high melting point in the homopolymerization of propylene, and a production method of an olefin polymer using the same. The metallocene complex of the present invention is represented by formula [I].