Synthesis and characterization of polyester‐imides from imidodicarboxylic acid monomers and ethylene glycol

Abstract

AbstractTwo monoimidodicarboxylic acids and four diimidodicarboxylic acids were synthesized from trimellitic anhydride and amino compounds, viz., glycine, p‐aminobenzoic acid, 4,4'‐diaminodiphenyl sulfide, 4,4'‐diaminodiphenyl ether, 4,4'‐diaminodiphenyl methane, and 4,4'‐diaminodiphenyl sulfide, and characterized by IR and 1H‐NMR spectroscopies and melting‐point determination. These functional monomers were condensed in N‐methyl‐2‐pyrrolidone solvent with ethylene glycol by a transesterification reaction to obtain the novel polyester‐imides with backbones of alternate imide‐ester linkages or imide‐imide‐ester‐ester linkages with SO2, O, CH2, or SS bridges in between. All the polymers were characterized by IR and 1H‐NMR spectroscopies, X‐ray diffraction, solution viscosity, solubility and solubility parameters, and differential thermal analysis. Most of the polymers possess amorphous structure and fairly high decomposition temperatures (450–485°C). These polymers having solubility parameters in the range δ 11.44–11.85, as determined by the group contribution technique, are soluble at room temperatures in aprotic polar solvents. © 1993 John Wiley & Sons, Inc.