A new facile and rapid synthesis of aliphatic polyamides by microwave-assisted polycondensation of omega-amino acids and nylon salts

A new facile method for the rapid synthesis of aliphatic polyamides was developed by using a domestic microwave oven by the polycondensation of both omega-amino acids and nylon salts in the presence of a small amount of a polar organic medium that acts as a primary microwave absorber. Suitable organic media were tetramethylene sulfone, amide-type solvents such as N-cyclohexyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidone, and phenolic solvents like m-cresol and o-chlorophenol. The polycondensation proceeded rapidly, compared with the conventional melt polycondensation, and was almost complete within 5 min, producing a series of polyamides with inherent viscosities around 0.5 dlg(-1).