POLYMERIC OLEFIN COMPOSITION FOR BOTTLE CLOSURES (OPTIONS), CLOSURE MANUFA CTURED THEREFROM, A METHOD FOR MANUFACTURING SUCH CLOSURE, AND BOTTLE CLOS ED BY THIS CLOSURE Russian patent published in 2004 - IPC

FIELD: polymer materials. SUBSTANCE: polymer composition for manufacturing bottle closures, in particular screw bottle closures, contains 90 to 100 wt % of crystalline propylene homopolymer or random propylene/C₂-C₁₀-α-olefin copolymer and o to 10 wt % of elastomeric ethylene/C₃-C₁₀-α-olefin copolymer, said crystalline propylene homopolymer or random copolymer containing at least 94 wt % of fraction insoluble in xylene at room temperature. Composition is characterized by value of modulus of elasticity on bend at 23(r) at least 1620 MPa, yield point at 23(r) at least 33 MPa, and Isode shock strength at 0(r) at least 2.5 kJ/m². Compositions are suited to be used in contact with foods and drinks, while closures made from these compositions can be subjected to heat treatments, in particular in the form of pasteurization cycles. EFFECT: enhanced useful characteristics of polymeric compositions. 15 cl, 2 tbl, 7 ex