Bottle closures made of polyolefins
AssigneeMontell Technology Company BV
InventorsSilvio Pitteri, Rainer Schweda, Antonella Angelini
Life of this patent
Estimating the term…
Abstract
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.
Claims10
A bottle closure comprising an olefin polymer composition (A) which comprises:
- 1) 90-100% by weight of a crystalline propylene homopolymer or random copolymer thereof with 0.5-6% by weight of a comonomer selected from ethylene and a C4-C10 α-olefin;
- said polymers containing at least 94% by weight of a fraction insoluble in xylene at room temperature (Polymer (1));
- and
- 2) 0-10% by weight of an elastomeric copolymer of ethylene with propylene or a C4-C10 α-olefin or mixtures thereof and, optionally, from 0.5 to 10% by weight of a diene, the said elastomeric copolymer containing from 40 to 85 mole % of ethylene (Polymer (2));
- provided that when the amount of Polymer (2) is 0% by weight, Polymer (1) is selected from the above said random copolymers;
- said composition (A) having a flexural elastic modulus value at 23° C. at least of 1620 MPa;
- a value of the strength at yield at 23° C. at least of 33 MPa;
- and an IZOD impact resistance value at 0° C. at least of 2.5 kJ/m2.
Dependencies are inferred from the claim text.