A colorless fluorinated diamme, 3'-trifluoromethyl-3,4'-oxydianiline (3'-CF3,-3,4'-ODA) (II) was prepared through the nucleophilic substitution reaction of 3-nitrophenol and 2-chloro-5-nitrobenzotrifluoride by catalytic reduction with hydrazine and Pd/C. A series of Polyimides V were synthesized from the diamine II with various aromatic dianhydrides IIIa-f via thermal and chemical imidization. These polyimides had inherent viscosities ranging from 0.88 to 1.12 dl/g. A comparison of V, VI to analogous polyimides VII, VIII. VI, VII and VIII was based on 3'4-ODA, 3-CF3-4,4'-ODA, 4,4'-ODA, respectively. In terms of the color of PI revealed that the color intensity of phenoxy-containing amine of the meta-structure and the para-structure with the CF3 group would fell off color intensity. The color intensity of the four polyimide series was lessened in the following order: V > VII > VI > VIII. The solubility of V is better than VI, VII and VII. The polyimide V films had a tensile strength ranging from 124 to 147 MPa, elongation at break from 9 to 65%, and initial modulus from 2.3 to 2.8 GPa. The glass transition temperature of polymers was recorded at 234-313 degreesC. They had 10% weight loss at a temperature above 515 degreesC and left more than 50% residue even at 800 degreesC in nitrogen. Compared with polyimides VI, V showed the lower dielectric constants of 2.80-3.50 (40 MHz), and moisture absorptions in the range of 0.44-1.02 wt%. (C) 2003 Elsevier Ltd. All rights reserved.