Patent ID: 7662901

Claim:
A composition comprising: a propylene homopolymer produced in a bulk polymerization process in the presence of a Ziegler-Natta catalyst comprising a first internal donor, a second internal donor, and an external donor, wherein the first internal donor is a phthalate and the second internal donor is one of a diether or a succinate, further wherein the external donor is selected from the group consisting of cyclohexylmethyldimethoxysilane, cyclohexylethyldimethoxysilane, diphenyldimethoxysilane, phenyltriethoxysilane, 3,3,3-trifluoropropylmethyldimethoxysilane, diisopropyldimethoxysilane, octylmethyldimethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, n-propyltrimethoxysilane, di-t-butyldimethoxysilane, cyclopentyl 1,1-dimethyl-2,2-dimethylethyldimethoxysilane and diamino silanes, the propylene homopolymer having a xylene soluble content of less than 2 percent, and a xylene insoluble fraction having a meso pentad content of greater than 96 percent and an average meso run length of at least 140, the propylene homopolymer having a melt flow rate of at least to 20 dg/min but less than 60 dg/min.