Polyquinoxalines Containing p-Phenylene Ether and p-Phenylene Moieties

: A series of quinoxaline polymers containing p-phenylene ether and p-phenylene moieties were prepared by polymerization of 3,3-diaminobenzidine with various aromatic bisglyoxals in m-cresol. The glass transition temperature (Tg) of the polyquinoxalines varied from 133C for a polymer highest in p-phenylene ether content to 350C for a polymer containing rigid p-phenylene moieties. Although thermalgravimetric analysis failed to show any distinct difference between the p-phenylene ether and the p-phenylene polymers, isothermal weight loss study at 400C in air showed that the p-phenylene polymers lost less weight after a given time than the p-phenylene ether polymers. Prior to polymer work, a series of quinoxaline model compounds were prepared to aid in polymer characterization. (Author)