A new aromatic diamine, 4-(4-trifluoromethylphenyl)-2,6-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]pyridine (9FPBAPP), was prepared from 4-(4-trifluoromethylphenyl)-2,6-bis(4-hydroxyphenyl)pyridine with 2-chloro-5-nitrotrifluoromethylbenzene by substitution and reduction reactions successively. A series of fluorinated copoly(pyridine ether imide)s were prepared from 4,4-oxydianiline (ODA), pyromellitic dianhydride and 9FPBAPP by thermal imidization procedure with various mole ratios of ODA and 9FPBAPP. All polymers were amorphous and soluble in organic solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone, and had T(g)s of 285.8-310.0 degrees C, 5% weight loss temperature of 545.5-565.7 degrees C in nitrogen atmosphere. Tough and flexible polymer films also exhibited excellent mechanical properties with tensile strengths of 76.3-96.5MPa, tensile moduli of 1.3-1.8GPa, elongations at break of 15.6-25.1%, low dielectric constants of 3.04-3.51 (1MHz) and water uptake of 0.44-0.65%, as well as high optical transparency with an ultraviolet-visible absorption cutoff wavelength in the 382-412nm range.