SYNTHESIS OF AROMATIC POLYAMIDES FROM N,N'-BIS(TRIMETHYLSILYL)-SUBSTITUTED AROMATIC DIAMINES AND AROMATIC DIACID CHLORIDES

A novel and facile method for the synthesis of high molecular weight aramids has been developed by the use of N,N prime -bis(trimethylsilyl)-substituted aromatic diamines which were found to be more reactive toward aromatic diacid chlorides than the parent unsubstituted diamines. The low-temperature solution polycondensation of the N-silylated aromatic diamines with aromatic diacid chlorides afforded readily a series of aramids having inherent viscosities of 2. 4-7. 4 dL multiplied by (times) g** minus **1 with the elimination of trimethylsilyl chloride under neutral and milder reaction conditions, compared with the conventional diamine-diacid chloride method.