PREPARATION AND PROPERTIES OF AROMATIC POLYAMIDES AND AROMATIC POLYESTERS DERIVED FROM 4,4'-SULFONYLDIBENZOIC ACID

Aromatic polyamides (aramids) having inherent viscosities of 0.3–1.6 dL/g were prepared by the direct polycondensation of 4,4′‐sulfonyldibenzoic acid with various aromatic diamines using triphenyl phosphite and pyridine as condensing agents. Aromatic polyesters (polyarylates) with inherent viscosities of 0.3–1.2 dL/g were prepared by the phase‐transfer catalyzed, two‐phase polycondensation of 4,4′‐sulfonyldibenzoyl chloride with various bisphenols. Most of the aramids and some polyarylates were soluble in a variety of solvents such as dimethylacetamide, N‐methyl‐2‐pyrrolidone, and m‐cresol, and afforded transparent, flexible, and tough films from the polymer solutions. The aramids and the polyarylates had glass transition temperatures in the range of 200–350 and 260–310°C, respectively. These polymers containing sulfonyl group did not lose weight below 350°C, with 10% weight loss being recorded above 430°C in air. Copyright © 1990 John Wiley & Sons, Inc.