Thermal degradation of polymers. Part XVIII. The synthesis and characterization of quinazolone pre‐polymers

Abstract

SynopsisA series of quinazolone pre-polymers have been prepared from 4,4'-diaminodiphenyl-3,3'-dicarboxylic acid and aromatic diacetamido compounds by melt polycondensation. The pre-polymers have been characterized by combustion analysis, viscometry, vapor pressure osmometry, and thermal analytical methods (TG, DTA, and DSC). Structures have been elucidated by spectroscopic methods (IR and NMR). The thermal cyclization of these pre-polymers to the partial ladder polyquinazolone has been studied and optimized using IR, DSCDTA, TG, and evolved gas analysis. The cyclization behavior of these systems has been resolved in terms of concurrent dehydration and decarboxylation.