Semi-continuous process for synthesis of polybenzazole polymers

US5219981A · kind A · utility

Assignee

• THE DOW CHEMICAL COMPANY · US

Inventors

• Thomas D. Gregory · Midland, US
• Carl W. Hurtig · Saginaw, US
• Harvey D. Ledbetter · Pinehurst, US
• Kenneth J. Quackenbush · Saginaw, US
• Steven Rosenberg · Burekup, AU

Key dates

• Filing date: Mar 1, 1991
• Grant date: Jun 15, 1993
• Expiry date: Mar 1, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G75/32
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polybenzazole polymers can be synthesized rapidly in large quantities at high molecular weight and high concentration by a two-step process of forming oligomers in a batch reactor and advancing the molecular weight of the polymer in an extruder.