Thermal degradation of poly(phenylene oxides)

The thermal degradation in vacuum of a number of halogenated poly(phenylene oxide) polymers has been studied by a weight loss method. In general the thermal stability decreased as the degree of substitution in the phenylene nuclei increased. The chloro derivatives were relatively more stable than the corresponding bromo derivatives. The majority of the polymers showed an initial rapid loss in weight followed by the formation of a highly stable residue. The good thermal stability of the simpler poly(phenylene oxides), coupled with their fusibility and solubility, indicate that they may be useful starting products for the preparation of practical materials.