Process for making low-density polyolefins

US6559251B1 · kind B1 · utility

Assignee

• Equistar Chemicals, LP · US

Inventors

• Shaotian Wang · Mason, US
• Clifford C. Lee · Houston, US
• Mark P. Mack · Sharonville, US
• Gregory G. Hlatky · Morrow, US
• Sandor Nagy · Naperville, US
• Barbara M. Tsuie · Cincinnati, US

Key dates

• Filing date: Aug 2, 2002
• Grant date: May 6, 2003
• Expiry date: Aug 2, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/943
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for making ethylene copolymers is disclosed. Ethylene copolymerizes with an &agr;-olefin in the presence of a catalyst system comprising an activator and a silica-supported, bridged indenoindolyl metal complex having &#8220;open architecture.&#8221; The supported complex incorporates comonomers with exceptional efficiency, and the process gives ethylene copolymers having high molecular weights (Mw>100K) and very low densities (<0.910 g/cm3). Open architecture catalysts that include bridging through the indolyl nitrogen of the indenoindolyl framework are also described.