Preparation and properties of polyamides from 4-phenoxy- and 4-phenylthio-m-phenylenediamine and both aromatic and aliphatic diacids

New soluble aramids having pendant phenoxy and phenylthio groups were prepared in high molecular weights by the polycondensation of aromatic diacids with 4-phenoxy-m-phenylenediamine and 4-phenylthio-m-phenylenediamine, respectively. Glass transition temperatures (T_g) of these aramids were in the range 195–255°C, where T_gs of phenoxy pendant aramids were higher than those of phenylthio substituted aramids. These properties were compared with those of the parent aramids derived from m-phenylenediamine and aromatic diacids. Aromatic-aliphatic polyamides were also prepared by the reaction of these three diamines with aliphatic diacids having 4–10 methylene groups and were characterized in detail.