N,N′-Pyromelliticdiimido-di-L-amino acids (1a–1d) were prepared from the reaction of pyromellitic dianhydride with the corresponding L-amino acids in a solution of glacial acetic acid/pyridine (3:2) at refluxing temperature. 4,4′-sulfonyl bis(4,1-phenylene) bis(diazene-2,1-diyl) diphenol, 4,4′-oxy bis(4,1-phenylene) bis(diazene-2,1-diyl) diphenol and 4,4′-methylene bis(4,1-phenylene) bis(diazene-2,1-diyl) diphenol, were prepared from 4,4′-diamino diphenyl sulfone, 4,4′-diamino diphenyl ether, 4,4′-diamino diphenyl methane, sodium nitrite and phenol following the general procedure of diazo coupling. Interfacial polycondensation method was used to prepare the corresponding poly(azo-ester-imid)s (>PAEI1–12) in biphasic solution of water/dichloromethane. The resulting polymers (>PAEIs) have been obtained in high yields having good inherent viscosities (0.32–0.57 dl g−1), optical activities and thermal stabilities.
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