Synthesis of Polyamides by Direct Polycondensation with Propylphosphonic Anhydride as an Activating Agent

Abstract

A 50 wt% solution of the propylphosphonic anhydride in NMP as an activating agent was used for the synthesis of amides and polyamides. The activating agent was useful for the preparation of amides from carboxylic acids and amines. The direct polycondensation of dicarboxylic acids with aromatic diamines using the activating agent in the presence of pyridine proceeded at 100°C to produce polyamides with inherent viscosities up to 1.6 dl g−1. Furthermore, the activating agent was used for the chemoselective polyamidation; that is, polyamides from dicarboxylic acids and diamines containing various functional groups were prepared without special protection of the acylation-sensitive groups.