| 摘要 |
PURPOSE:To obtain a new bisanilinefluorene which is suitably used as a starting substance for polyimide resins or polyamide resins having charging groups in the molecule, and excellent heat resistance and solubility in solvents. CONSTITUTION:A compound of the formula (R1 to R4 are H, 1 to 3C alkylene), for example, 9,9-bis(3-methyl-4-aminophenyl)fluorene-4-carboxylic acid. The compound is obtained by heating diphenic acid in sulfuric acid to convert into fluorenonecarboxylic acid, heating the product in an aniline using an aniline hydrochloride as a catalyst to effect the reaction as the water liberated by condensation reaction is removed out of the system, neutralizing the mixture after completion of the reaction, washing the product in boiling water, filtering the precipitate, further rinsing the precipitate and drying. The polyimide resin therefrom is suitably used as a membrane for separation of a liquid system or as an ion-exchange membrane. |
