A catalyst component for olefin polymerization includes magnesium, titanium, a halogen, an internal electron donor compound, and a precipitation aid. The precipitation aid includes a precipitation aid represented by general formula (I). The precipitation aid represented by general formula (I) includes isomers represented by general formula (I-a) and/or (I-b). ##STR00001##

A polypropylene composition made from or containing: A) from 60 to 90 wt %, based upon the total weight of the polypropylene composition, of a fraction insoluble in xylene at 25 C., is made from or containing more than 80% wt of propylene units, and B) from 10 to 40 wt %, based upon the total weight of the polypropylene composition, of a fraction soluble in xylene at 25 C. is made from or containing a copolymer of propylene and ethylene having an average content of ethylene derived units from 30.0 wt % to 55.0 wt %, wherein the fraction when subjected to GPC fractionation and continuous IR analysis for determining the ethylene content of the eluted fractions (GPC-IR analysis), shows that the content of ethylene increases along with the Mw for fractions having Mw higher than the average.