Poly(N-arylenebenzimidazoles) via aromatic nucleophilic displacement

US5410012A · 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: Mar 5, 1993
• Grant date: Apr 25, 1995
• Expiry date: Mar 5, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G73/18
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Novel poly(N-arylenebenzimidazole)s (PNABIs) are prepared by the aromatic nucleophilic displacement reaction of novel di(hydroxyphenyl-N-arylene benzimidazole) monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl-N-arylenebenzimidazole) monomers are synthesized by reacting phenyl-4-hydroxybenzoate with bis(2-aminoanilino)arylenes in diphenylsulfone. Moderate molecular weight PNABIs of new chemical structures were prepared that exhibit a favorable combination of physical and mechanical properties. The use of the novel di(hydroxyphenyl-N-arylenebenzimidazole)s permits a more economical and easier way to prepare PNABIs than previous routes.