a highly crystalline polypropylene for forming film which is obtained by subjecting to the molecular weight degradation a propylene homopolymer obtained by the polymerization of propylene over a stereoregulating catalyst and which has : a melt flow rate , mfr , in the range of 1 to 10 min determined in accordance with astm - d - 1238 ; a ratio q which is the ratio of weight average molecular weight m w to the number average molecular weight m n , namely , m w / m n , in the range of 2 . 5 to 4 . 0 ; a density of at least 0 . 9070 g / cm 3 or more ; the cold xylene soluble matter in the range of 2 . 5 % by weight at the highest . the highly crystalline polypropylene will produce film endowed with good transparency , stiffness , impact strength and resistance to blocking , in improved cost performance , which could to some extent be antagonistic to each other .