Heterophasic propylene ethylene copolymer composition with desirable balance of mechanical properties

A heterophasic propylene ethylene copolymer composition having an MFR2 measured according to ISO 1333 at 230° C. and 2.16 kg in the range from 1.0 to 55.0 g/10 min and a melting temperature (Tm) measured by differential scanning calorimetry (DSC) in the range from 155 to 162° C., comprising:

• a) a crystalline matrix (M) being a propylene homo-or copolymer;
• b) an amorphous propylene-ethylene elastomer (E);
• wherein the heterophasic propylene ethylene copolymer composition is characterized in terms of its soluble fraction (SF) and crystalline fraction (CF) as determined by CRYSTEX analysis obtained through temperature cycles of dissolution at 160° C., crystallization at 40° C. and re-dissolution in 1,2,4-trichlorobenzene at 160° C.:
• i) from 60 to 88 wt. %, based on the total weight of the heterophasic propylene ethylene copolymer composition, of a crystalline fraction (CF) having an intrinsic viscosity iV(CF) measured according to DIN ISO 1628/1, October 1999 (in Decalin at 135° C.) in the range from 1.40 to 2.50 dl/g, a an isotactic pentad concentration [mmmm] as determined by 13C-NMR spectroscopy of more than 97.0% and a content of 2,1-regiodefects in the range from 0.1 to 0.4 mol %,
• ii) from 12 to 40 wt. %, based on the total weight of the heterophasic propylene ethylene copolymer composition, of a soluble fraction (SF) having an intrinsic viscosity iV(SF) measured according to DIN ISO 1628/1, October 1999 (in Decalin at 135° C.) in the range from 1.80 to 3.20 dl/g and an ethylene content C2(SF), as determined by quantitative 13C-NMR spectroscopy, in the range from 25 to 80 wt. %,
• wherein the ratio of the intrinsic viscosities of the two fractions, iV(SF)/iV(CF), is in the range from 1.25 to 2.0.