A new dicarboxylic acid chloride (2) bearing three preformed imide rings was synthesized by treating N-(3,5-diaminophenyl) phthalimide with trimellitic anhydride followed by refluxing with thionyl chloride. A novel family of aromatic poly(ester-imide)s with inherent viscosities of 0.27–0.35 dl g
1 were prepared from 2 with various bisphenols such as resorcinol (3a), hydroquinone (3b), 2,20-dihydroxybiphenyl (3c), 4,40-dihydroxybiphenyl (3d), bisphenol-A (3e), 2,20-dimethyl-4,40-dihydroxybiphenyl (3f), 1,5-dihydroxynaphthalene (3g), 2,7-dihydroxynaphthalene (3h), and 2,20- dihydroxy-1,10-binaphthyl (3i) by high-temperature solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher. All of the resulted polymers were fully characterized by FT-IR and NMR spectroscopy and elemental analyses. The poly(ester-imide)s exhibited excellent solubility in some polar organic solvents. From differential scanning calorimetry, the polymers showed glass-transition temperatures between 259 and 353
C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis and the 10% weight loss temperatures of the poly(ester-imide)s were found to be in the range between 451 and 482
C in nitrogen. Furthermore, crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction.

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