A novel monomer diacid, 6,6'-methylene-bis(2-oxo-2H-chromene-3-carboxylic acid), was synthesized and used in a direct polycondensation reaction with various aromatic diamines in N-methyl-2-pyrrolidone solution containing dissolved LiCl and CaCl2, using triphenyl phosphite and pyridine as condensing agents to give a series of novel heteroaromatic polyamides containing photosensitive coumarin groups in the main chain. Polyamide properties were investigated by DSC, TGA, GPC, wide-angle X-ray scattering, viscosity, and solubility measurements. The copolymers were soluble in aprotic polar solvents, and their inherent viscosities varied between 0.49 and 0.78 dL g(-1). The weight-average and number-average molecular weights, measured by gel permeation chromatography, were 27,500-43,900 g mol(-1) and 46,500-66,300 g mol(-1), respectively, and polydispersities in the range of 1.48-1.69. The aromatic polyamides showed glass-transition temperatures (T-g) ranging from 283 to 329 degrees C and good thermal properties evidenced by no significant weight loss up to 380 degrees C and 10% weight loss recorded above 425 degrees C in air. All the polyamides exhibited an amorphous nature as evidenced by wide-angle X-ray diffraction and demonstrated a film forming capability. Water uptake values up to 3.35% were observed at 65% relative humidity. These polymers exhibited strong UV-vis absorption maxima at 357-369 nm in DMSO solution, and no discernible photoluminescence maxima were detected by exciting with 365 nm. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 1450-1458, 2010