MULTIMODAL POLYETHYLENE COMPOSITION AND FILM INCLUDING IT Russian patent published in 2021 - IPC C08F2/00 C08F2/01 C08F2/12 C08F2/18 C08J5/18 C08L23/04 C08L23/06 B01J19/00 

FIELD: polyethylene production.

SUBSTANCE: group of inventions relates to a multimodal polyethylene composition for molding, as well as to film containing a composition for molding. The composition includes: (A) from 40 to 62% by weight of low molecular weight polyethylene, wherein low molecular weight polyethylene has weighted average molecular weight (Mw) from 20,000 to 90,000 g/mol, and has a MI₂ value from 500 to 1000 g/10 minutes according to ASTM D 1238 standard; (B) from 8 to 20% by weight of ultra-high molecular weight polyethylene having weighted average molecular weight (Mw) from more than 1,000,000 to 5,000,000 g/mol; and (C) from 30 to 50% by weight of high molecular weight polyethylene having weighted average molecular weight (Mw) from more than 150,000 to 1,000,000 g/mol. The density of ultra-high molecular weight polyethylene and high molecular weight polyethylene is in the same range from 0.920 to 0.950 g/cm³. The molecular weight distribution of the multimodal polyethylene composition ranges from 24 to 28, as measured by gel-penetrating chromatography, and the multimodal polyethylene composition has a MI₂ value of 0.03 to 0.15 g/10 minutes. Films containing the composition for molding have thickness from 4 to 40 mcm.

EFFECT: creation of high-density polyethylene compositions for the formation of inflatable films having improved properties in terms of high performance, good stability of the film sleeve, high mechanical strength and high impact strength, with film thicknesses from 4 to 40 microns (mcm) or preferably less.

8 cl, 3 tbl, 5 ex