COMPOSITION BASED ON STATISTICAL PROPYLENE COPOLYMERS, PROCESS FOR PREPARING THE SAME AND MULTILAYER HEAT-SEALABLE SHEETS

摘要

The invention relates to a composition based on statistical propylene copolymers, to a process for preparing said composition and to multilayer heat-sealable sheets. According to the invention, the composition comprises 68...80% by weight a propylene copolymer (A) containing 12...20% by weight units derived from 1-butene and up to 2% by weight units derived from ethylene and 32...25% by weight a statistical propylene copolymer (B) containing up to 15% by weight units derived from 1-butene and 1...8% by weight units derived from ethylene, the compositions of the two copolymers (A and B) being different. The multilayer heat-sealable sheets made by using the claimed process consist of a base layer comprising mainly a crystalline propylene copolymer which is bonded, laminated, coextruded with at least one sealing layer comprising mainly the claimed composition and, optionally, oriented by drawing.