Soluble fluorinated polyimides derived from 1,4- (4′-aminophenoxy)-2-(3′-trifluoromethylphenyl)benzene and aromatic dianhydrides

New fluorinated aromatic polyimides were prepared from 1,4-(4′-aminophenoxy)-2-(3′-trifluoromethylphenyl)benzene and aromatic dianhydrides via the polycondensation of one-step high-temperature and two-step thermal or chemical imidization methods. Experimental results indicated that some of the polyimides were soluble both in strong dipolar solvents (N-methyl-2-pyrrolidone or N,N-dimethylacetamide) and in common organic solvents such as tetrahydrofuran, CHCl3, and acetone. The polyimides showed exceptional thermal and thermooxidative stability and good mechanical properties. No weight loss was detected before a temperature of 520 °C in nitrogen, and the glass-transition temperatures ranged from 208 to 251 °C. Low dielectric constants (2.55–2.71 at 1 MHz), low refractive indices, and low water absorption were also observed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2404–2413, 2001