PROPYLENE/1-HEXENE COPOLYMER COMPOSITION WITH BROAD HEAT SEALING WINDOW Russian patent published in 2014 - IPC C08L23/12 C08L23/14 C08J5/18 C08F297/08 B32B27/32 

FIELD: chemistry.

SUBSTANCE: invention relates to a propylene copolymer composition, production and use thereof. The propylene copolymer composition contains polypropylene (A) with comonomer content of not more than 1.0 wt % and a propylene copolymer (B) with comonomer content of 4.0-20.0 wt %. Content of comonomers in the composition, which are C₅-C₁₂ α-olefins, is at least 2.5 wt %, and the ratio of melt flow rate of polypropylene (A) to the melt flow rate of the propylene copolymer (B) is less than 1.0. According to stepwise isothermal segregation technique (SIST) results, at least 20.0 wt % of the crystalline fraction has a lamella thickness greater than 5.70 nm and at least 10.0 wt % of the crystalline fraction has a lamella thickness less than 3.0 nm.

EFFECT: disclosed composition has low content of a fraction soluble in hexane, high hot seam strength and a broad heat sealing window at sufficiently low heat sealing initiation temperature (SIT).

15 cl, 1 dwg, 4 tbl, 8 ex