Polymer composition for caps and closures

US9976017B2 · kind B2 · utility

Assignee

• INEOS EUROPE AG · CH

Inventors

• Benoit Koch · Hannut, BE
• Christophe Moineau · Nivelles, BE

Key dates

• Filing date: Jan 5, 2015
• Grant date: May 22, 2018
• Expiry date: Jan 5, 2035

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2207/07
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polyethylene composition having a density of 950-960 kg/m3, a SHI(1,100) of 4-12, a melt index MI2 between 0.2 and 2 g/10 min, and a relationship between spiral flow ‘SF’ (measured in mm at 250° C./1000 bar/100 mm/s) and ESCR ‘E’ (measured in hours) of E>200−SF. The composition contains 48-62 wt % of an ethylene polymer (A) and 38-52 wt % of an ethylene copolymer (B). Copolymer (B) has a higher weight average molecular weight than polymer (A), and both of fractions (A) and (B) have a reverse comonomer distribution such that comonomer content increases with increasing molecular weight in the individual fraction.