A series of fluorinated polyamides was prepared directly by low-temperature polycondensation of a new cardo diacid chloride, 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene (BCPX), with various diamines containing trifluoromethyl substituents in N,N-dimethylacetamide (DMAc). Almost all polyamides showed excellent solubility in amide-type solvents such as DMAc and could also be dissolved in pyridine, in-cresol, and tetrahydrofuran. These polymers had inherent viscosities between 0.77 and 1.31 dL g(-1), and their weight-average molecular weights and number-average molecular weights were in the range of 69,000-102,000 and 41,000-59,000, respectively. The resulting polymers showed glass transition temperatures between 240-258 degrees C and 10% weight loss temperatures ranging from 484 degrees C to 517 degrees C and 410 degrees C to 456 degrees C in nitrogen and air, respectively, and char yields at 800 degrees C in nitrogen higher than 55%. All polymers were amorphous and could be cast into transparent, light-colored, and flexible films with tensile strengths of 81-100 MPa, elongations at break of 8-12%, and tensile modulus of 1.6-2.1 GPa. These polymers had low-dielectric constants of 3.34-3.65 (100 kHz), low-moisture absorption in the range of 0.76-1.91%, and high transparency with an ultraviolet-visible absorption cut-off wavelength in the 322-340 nm range. (C) 2010 Wiley Periodicals, Inc. I Appl Polym Sci 118: 2959-2968, 2010