Abstract: Firstly, a novel diamine monomer 9,9-bis (3, 5-dimethoxy-4-(4-amino-2-methylphenoxy) phenyl) containing fluorene was preparedby three-step organic reaction. This monomer was then used to synthesize a series of polyarylamides (PA 3a-3d) with fluorine by low-temperature solution condensation with four commercial aromatic diacids (terephthalic acid, 2, 2-bis (4-carboxyphenyl) hexafluoropropane,4, 4-diphenyl ether dicarboxylic acid, and 4-tert-butylisophthalic acid). The structure and properties of these polymers were characterized by ¹H NMR, FT-IR and GPC. The solubility, thermal properties, optical properties and mechanical properties of the polymers were investigated. The results showed that the polyarylamidescouldbe dissolved in high-boiling polar solvents such as DMAc, NMP, DMF, and pyridine and low-boiling point solvent THF. The glass-transition temperature T_g of these polymers ranged from 217℃ to 234℃. The 10% mass loss temperature in air and nitrogen were both above 450℃, indicating excellent thermal stability. The prepared films exhibited excellent mechanical properties, with tensile strength more than 76.6 MPa and elongation at break above 8.7%. These polymers with fluorene structures showed excellent comprehensive properties.

Key words: polyaramide, fluorenyl, thermostability, solubility, mechanical property