PROPYLENE-BASED POLYMER COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain the subject composition having excellent balance of rigidity, impact resistance (especially low-temperature impact resistance) and heat resistance by including a specific propylene block copolymer and an elastomer in a prescribed ratio. SOLUTION: This composition is obtained by compounding (A) 10-99 wt.% of a propylene block copolymer which comprises (i) a polymer block composed of a propylene homopolymer or a random copolymer of (a) propylene and (b) <=10 mol.% of a copolymerizable monomer of ethylene and/or a 4-20Cα-olefin and (ii) a polymer block composed of a random copolymer of the component (a) and 10-80 mol.% of the component (b), satisfying the equation nb <=n+1.5 (nb is the average chain length of block of the component (b); (n) is the total average chain length of the component (b)) and has 0.1-200 g/10 minutes melt flow rate with (B) 1-90 wt.% of an elastomer (e.g. ethylene/1-octene ccpolymer).