An imide ring-pel formed dicarboxylic acid bearing one hexafluoroisopropylidene and two ether linkages between aromatic rings, 2,2-bis[4-(4-trimellitimidophenoxy)phenyl]hexafluoropropane (II), was prepared from the condensation of 2,2-bis[4(4-aminophenoxy)phenyl] hexafluoropropane and trimellitic anhydride. A novel series of poly(amide-imide)s having:inherent viscosities of 0.72 similar to 1.86 dL g(-1) was prepared by the triphenyl phosphite-activated polycondensation from the diimide-diacid (II) with various aromatic diamines in a medium consisting of N-methyl-2-pyrolidone, pyridine, and calcium chloride. Several of the resulting polymers were soluble in polar amide solvents, and their solutions could be cast into transparent, thin, flexible films having good tensile properties and high thermal stability. The 10% weight loss temperatures were all above 495 degrees C in air or nitrogen atmosphere, and the glass transition temperatures were in the range of 237 degrees-276 degrees C.