Heat resistant, shapable, hydroxy and/or alkoxy-substituted polyamides derived from at least one diamine selected from unsubstituted and substituted 4,4'-bis[2-(4-amino-3-hydroxyphenyl)hexafluoroisopropyl)]diphenyl ether 4,4'-bis-[2-(3-amino-4-hydroxyphenyl)hexafluoroisopropyl]diphenyl ether and a dicarboxylic acid or a derivative thereof e.g. its acid halo or ester. The polyamides of the invention may be thermally cured to form polybenzoxazoles of higher heat resistance which are stable to hydrolytic, chemical and radiation attack.The polyamides of the invention may be formed into shaped articles by molding, extrusion and solvent casting processes preferably in the presence of a solvent or diluent and then optionally converted into heat resistant, insoluble polybenzoxazoles. These shaped articles are useful in aircraft, electronic and other commercial applications where heat, chemical and radiation resistance are desired in conjunction with good mechanical and electrical properties.