Progress in the Area of Degradation and Stabilization of Nylon 66

Abstract
The two principal commercial polyamides are poly(hexamethylene adipamide) (nylon 66) and polycaprolactam (nylon 6). They are produced by direct amidation of a diacid with a diamine and ring-opening polymerization of ɛ-caprolactam, respectively. Poly(hexamethylene adipamide) is synthesized by hexamethylene diamine and adipic acid [1]. A stoichiometric balance of amine carboxylic group is readily obtained by the preliminary formation of a 1:1 ammonium salt: