A new diimide-diacid, 2,2′-(5-(4-(4-(4,5-diphenyil-1H-imidazol-2-yl)phenoxy)phenylcarbam-oyl)-1,3-phenylenebis(1,3-dioxoisoindoline-5-carboxylic-acid)(DADA), was synthesized from the reaction between trimellitic anhydride and a new diamine, N-(4-(4-(4,5-diphenyl-1H-imidazole-2-yl)phenoxylphenyl)-3,5-diaminobenzamide(NIDA). The direct polycondensation of DADA with various diamines was carried out in NMP in the presence of triphenylposphite and pyridine as condensing agents. The resulting poly(amide-imide)s (PAIs) were amorphous, readily soluble in many polar aprotic solvents and showed inherent viscosities of 0.35–0.47 dL/g. According to thermal analysis, these polymers exhibited glass transition temperatures (Tgs) in the range of 207–271°C, and their initial decomposition temperature (Ti) varied from 260 to 330°C and temperature of 10% weight loss (T10) from 325 to 520°C in N2. These polymers in NMP solution exhibited strong UV–vis absorption maxima at 320 nm and their fluorescence emission peaks appeared around 425–450 nm. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.