To obtain the subject copolymer hardly having a content soluble in toluene at a low temperature and catalyst residue remaining in the polymer, having wide molecular weight distribution and useful as a material for various kinds of stretched films by carrying out random copolymerization of propylene with ethylene in the presence of a catalyst comprising a solid titanium com pound, etc.
This copolymer has 0.1-30g/10min melt flow rate and is composed of 0.1-15mol% monomer unit based on ethylene and 85-99. 9% monomer unit based on propylene and has a relationship between monomer unit E based on ethylene and a content S (wt.%) soluble in toluene at a low temperature satisfying the formula S≤0.37×E+1.5 and has a ratio of weight average molecular weight to number average molecular weight measured by gel permeation chromatography of ≥6, ≤3ppm titanium atom and ≤30ppm chlorine atom. The copolymer is obtained by carrying out random copolymerization of propylene with ethylene in the presence of a solid catalyst comprising (A) a solid titanium compound consisting essentially of Mg, Ti and a halogen, (B) an organoaluminium compound and (C) dicyclopentyldimethoxysilane.
KITAJIMA YOSHIYUKI
ITO JUNICHI
