Ionic liquid mediated synthesis of 4, 4'diamino azo benzene substituted aliphatic polyamides and thermal studies

Abstract

Ionic liquids act as green solvents, which can replace the usual traditional solvents which pose both environmental and biological hazard. In the present work 4,4'diamino azobenzene has been condensed with various aliphatic diacids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid and Pimelic acid using imidazolium based ionic liquids in the presence of triphenylphosphite(TPP). The resulting azopolyamides have been obtained in high yield with intrinsic viscosity ranging from 0.56 - 0.81 dlg^-1. This method is compared with modified Higashi’s method. The thermodynamic parameters like DG, DH and DS are calculated by approximate methods such as Freeman & Carroll, Coats & Red fern, Doyle and Murray and White. The resulting polyamides prepared using green condition show increased thermal stability when compared to polyamides prepared by modified Higashi’s method.