Formation of large cyclic amides by catalytic depolymerization of polyamides

Abstract Nylon 8, nylon 12, nylon 6.6, nylon 11.6 and nylon 12.12 were thermally converted into cyclic oligomers at 280 to 330°C within one to three hours. The reaction is catalyzed by small amounts of salts of different carboxylic acids and is supposed to take place by an anionic depolymerization mechanism.