关键词: 聚芳酰胺, 透明性, 溶解性, 三氟甲基

Abstract: A novel fluorinated diamine monomer, 1,4-bis[4-amino-2-(trifluoromethyl)phenoxy]cyclohexane, was synthesized via two steps using 2-chloro-5-nitrobenzotri?uoride and 1,4-cyclohexanediol as the starting materials, which was subsequently employed to prepare a series of fluorinated aromatic polyamides with various aromatic acids, terephthalic acid, isophthalic acid, 4,4'-oxydibenzoic acid, and 2,2-bis(4-carboxy-phenyl)hexa?uoropropane. The inherent viscosities of the resulted polyamides were in range of 0.89~1.29 dL/g, and they exhibited excellent solubility and optical property. They could be readily dissolved in not only strong polar solvents such as N-methy-2-pyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide, but also in some low-boiling-point solvents such as tetrahydrofuran, chloroform, and dichloromethane. The film prepared from these polyamides was colorless and transparent, with a UV-vis absorption edge between 335 nm and 357 nm. Furthermore, the polyamides also showed good thermal properties. The temperature of 10 % weight loss was 330~364 °C under nitrogen atmosphere. The glass-transition temperatures (Tgs) were in the range of 202~223 °C.

Key words: aromatic polyamides, transparency, solubility, trifluoromethyl