Abstract

A general overview of polyamide technology is presented, with emphasis on commercial practice and technology developed since 1980. The article includes coverage of nomenclature; history; economic, health, and environmental aspects; and physical properties, including crystallinity, solubility, and piezoelectric effects. There is an extensive discussion of chemical properties including methods of preparation (direct amidation, reaction of acid chlorides, and ring-opening polymerization of lactams via hydrolytic, anionic, and cationic processes); chemical reactions (acidolysis, aminolysis, alcoholysis, ammonolysis, transamidation, transesteramidation, and grafting); and degradation reactions (hydrolysis, thermal degradation, thermooxidation, photodegradation and photooxidation, biodegradation, and mechanodegradation). The manufacturing practices for most commercial nylons that are presented include monomer production for nylon-6,6, nylon-6, nylon-4,6, nylon-6,9, nylon-6,10, nylon-6,12, nylon-11, nylon-12, nylon-12,12, and nylon-13,13. Nylon-6,6 and nylon-6 are compared in detail. There are also discussions of copolyamides, mixed aliphatic–aromatic, and wholly aromatic polyamides. Extensive tables are presented which list CAS Registry Numbers, physical properties, and world-wide manufacturers of most polyamides.