Bottle closures made of polyolefins

摘要

A bottle closure made from an olefin polymer composition (A) which includes: 1) 90-100% by weight of a crystalline propylene homopolymer or propylene/C2-C10 alpha-olefin random copolymer, those polymers containing at least 94% by weight of a fraction insoluble in xylene at room temperature; and 2) 0-10% by weight of an ethylene/C3-C10 alpha-olefin elastomeric copolymer, provided that when the amount of polymer (2) is 0% by weight, polymer (1) is one of the above random copolymers. Said composition (A) has a flexural elastic modulus value at 23° C. of at least 1620 MPa, a strength at yield at 23° C. of at least 33 MPa, and an IZOD impact resistance at 0° C. of at least 2.5 kJ/m2.