POLYETHYLENE RESIN FOR PIPES WITH HIGH RESISTANCE TO SLOW CRACK GROWTH Russian patent published in 2024 - IPC C08L23/08 C08L23/06 F16L9/12 

FIELD: compositions for pipe material.

SUBSTANCE: disclosed is a polyethylene composition containing a base resin which contains (A) a first fraction of an ethylene homo- or copolymer and (B) a second fraction of an ethylene-hexene-1 copolymer, where fraction (A) has a lower molecular weight than fraction (B), and where fraction (B) is present in amount of 51.0 to 58.5 wt.% based on the total weight of the base resin, where fraction (B) of the base resin has a content of units derived from hexene-1 from 0.80 to 1.45 mol.%, where the base resin has a number average molecular weight Mn of 8,500 g/mol or more, and where the polyethylene composition has a melt flow rate MFR₅ of 0.10 to 0.30 g/10 min. Also disclosed is a method of producing said composition, a pipe and a pipe fitting containing said composition, as well as use of said composition to produce an article selected from a pipe and a pipe fitting.

EFFECT: disclosed composition enables to obtain pipes with improved resistance to rapid propagation of cracks and good impact resistance.

18 cl, 4 tbl