Bimodal polyethylene composition and articles made therefrom

US7825190B2 · kind B2 · utility

Assignee

• DOW GLOBAL TECHNOLOGIES LLC · US

Inventors

• Jozef Van Dun · Horgen, CH
• Patrick J. C. Schouterden · Wachtebeke, BE
• Kalyan Sehanobish · Rochester Hills, US
• Peter F. van den Berghen · Graauw, NL
• Noorallah Jivraj · Lake Jackson, US
• Johan Vanvoorden · Diepenbeek, BE
• Ruddy Nicasy · Westerlo, BE
• Ravi S. Dixit · Midland, US
• Frederik E. Gemoets · Wommelgem, BE

Key dates

• Filing date: Jan 11, 2008
• Grant date: Nov 2, 2010
• Expiry date: Jan 11, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2314/06
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to a polyethylene composition with a bimodal molecular weight distribution and articles made therefrom, such as high topload blow moldings and transmission and distribution pipes. The composition comprises a low-molecular-weight (LMW) ethylene homopolymer component and a homogeneous, high-molecular-weight (HMW) ethylene interpolymer component, wherein the LMW component is characterized as having a molecular weight distribution, MWDL, of less than about 8. The composition is characterized as having a bimodal molecular weight distribution, and a ductile-brittle transition temperature, Tdb, of less than −20° C. In some embodiments, the HMW component is characterized by a reverse comonomer distribution.