Polybenzimidazole via aromatic nucleophilic displacement

US5317078A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• John W. Connell · Newport News, US
• Paul M. Hergenrother · Yorktown, US
• Joseph G. Smith, Jr. · Smithfield, US

Key dates

• Filing date: Oct 30, 1991
• Grant date: May 31, 1994
• Expiry date: Oct 30, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D235/18
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Di(hydroxyphenyl)benzimidazole monomers were prepared from phenyl-4-hydroxybenzoate and aromatic bis(o-diamine)s. These monomers were used in the synthesis of soluble polybenzimidazoles. The reaction involved the aromatic nucleophilic displacement of various di(hydroxyphenyl)benzimidazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds in the presence of an alkali metal base. These polymers exhibited lower glass transition temperatures, improved solubility, and better compression moldability over their commercial counterparts.