Polymers

US8772426B2 · kind B2 · utility

Assignee

• INEOS MANUFACTURING BELGIUM NV · BE

Inventors

• Choon Kooi Chai · Overijse, BE
• Luc Dheur · Brussels, BE
• Benoit Koch · Hannut, BE
• Stefan Klaus Spitzmesser · Brussels, BE

Key dates

• Filing date: Jan 18, 2011
• Grant date: Jul 8, 2014
• Expiry date: Feb 14, 2031

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F210/16
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Copolymers of ethylene and α-olefins having (a) a density (D) in the range 0.900-0.940 g/cm3, (b) a melt index MI2 (2.16 kg, 190° C.) in the range of 0.01-50 g/10 min, (c) a melt index MI2 (2.16 kg, 190° C.) and Dow Rheology Index (DRI) satisfying the equation [DRI/MI2]>2.65, and (d) a Dart Drop Impact (DDI) in g of a blown film having a thickness of 25 μm produced from the copolymer satisfying the equation DDI≧1900×{1−Exp [−750(D−0.908)2]}×{Exp [(0.919−D)/0.0045]}. The copolymers may be prepared using metallocene catalysis and are preferably prepared in multistage processes carried out in loop reactors in the slurry phase. The copolymers exhibit long chain branching as defined by Dow Rheology Index (DRI) and exhibit unexpected improvements in mechanical properties, in particular dart drop impact, when extruded into blown films.