SYNTHESES AND PROPERTIES OF RELATED POLYOXADIAZOLES AND POLYTRIAZOLES

New aromatic poly-1,2,4-triazoles and poly-1,3,4-oxadiazoles are studi ed as thermally stable membrane materials. Various groups were introdu ced onto the pendant phenyl groups of poly-1,2,4-triazoles. Glass tran sition temperature, degradation temperature, and cold crystallization behavior were studied as a function of these groups. Cold crystallizat ion appeared to be highly sensitive to macromolecular regularity. The solubility of poly-1,3,4-oxadiazoles was highly improved upon incorpor ation of 5-t-butylisophthalic, 1,1,3-trimethyl-3-phe-nylindane, 4,4'-( 2,2'-diphenyl)hexafluoro propane, and diphenyl ether groups into the p olymeric main chain, whereas the high glass transition temperatures an d degradation temperatures typical for aromatic poly-1,3,4-oxadiazoles were maintained. (C) 1994 John Wiley & Sons, Inc.