Preparation and properties of polybenzimidazoles containing cardo groups

✍ Scribed by Srinivasan, P. R. ;Mahadevan, V. ;Srinivasan, M.

• Publisher: John Wiley and Sons
• Year: 1982
• Weight: 493 KB
• Volume: 20
• Category: Article
• ISSN: 0360-6376
• DOI: 10.1002/pol.1982.170201105

✦ Synopsis

Abstract

Several polybenzimidazoles containing cardo groups were prepared: A cardodicarboxylic acid, 9,9‐bis(4‐carboxyphenyl)fluorene, and two cardotetramines, 9,9‐bis(3,4‐diaminophenyl)fluorene and 9,9‐bis(3,4‐diaminophenyl)10‐anthrone. The cardodicarboxylic acid was condensed with aromatic tetramines and the cardotetramines were condensed with aromatic dicarboxylic acids. Prior to polymer synthesis two model compounds, 9,9‐bis[4,(2‐benzimidazolyl)phenyl]fluorene and 2,2′‐diphenyl‐5,5′‐(9,9‐fluorenediyl)‐bibenzimidazole were prepared and characterized by spectral methods. The polymers were obtained in 60–70% yield and showed reduced viscosity in the range of 0.7–1.1 dL/g. They were soluble in dimethyl formamide (DMF) and chlorinated solvents like tetrachlorethane. The thermal stabilities of these cardopolymers were superior to noncardopoly‐benzimidazoles.