Process for preparing low molecular weight polymers

US5328972A · kind A · utility

Assignee

• Rohm and Haas Company · US

Inventors

• Emmanuel A. Dada · Bensalem, US
• Willie Lau · North Wales, US
• Richard Foster Merritt · Fort Washington, US
• Yi H. Paik · Princeton, US
• Graham Swift · Chapel Hill, US

Key dates

• Filing date: Sep 28, 1992
• Grant date: Jul 12, 1994
• Expiry date: Sep 28, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/54
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for preparing polymers having molecular weights below 5,000 and polydispersity below 2.5 is provided. The polymerization is conducted in supercritical carbon dioxide at temperatures of at least 200.degree. C. and pressures above 3,500 psi. The process can be continuous, semi-continuous, or batch. The polymers are useful as detergent additives, scale inhibitors, dispersants and crystal growth modifiers.