Molten tetrabutylammonium bromide as eco-friendly media for the synthesis of optically active and thermal stable polyamides under microwave irradiation

Abstract

The present paper is an extension of microwave method describing the synthesis of optically active polyamides (PAs). The main focus of this work is the design of effective microwave method for preparing of optically active PAs. The diacid containing amino acid and 1,8-nuphthaIimide group wax prepared in three steps. For the preparation of optically active polymers from this monomer the polycondensation reactions of diacid 7 with different aromatic and aliphatic diisocyanates was employed in the presence of a small amount of tetrabutylammonium bromide as ionic liquid media that acts as a primary microwave absorber and was compared with conventional heating. The resulting polymers were characterized using FT/IR, 1HNMR, 13CNMR, UV-vis spectroscopy, fluorimetry, specific rotation techniques and elemental analysis. Thermal properties of the resulting PAs were evaluated by thermograviraetric analysis and differential scanning caloriraerry. The interpretation of kinetic parameters (E. ΔH, ΔS and ΔG) of thermal decomposition stages have also been evaluated using Coats-Redfern and Dharwadkar-Kharkhanawala equations. © 2008 The Society of Polymer Science, Japan.