Thermal decomposition of polyamide-6 in the presence of PVC

Besides the monomer some minor but characteristic volatile thermal decompos ition products are observed pyrolysing polyamide-6 in the presence of PVC. It was proven that hydrogen chloride thermally eliminated from PVC gives ri se to facilitated depolymerization of PA-6, partial hydrolysis of the amide groups, evolution of 6-chlorohexanenitrile, and promoted nitrile and vinyl end group formation. A mechanism is proposed for the advance of these reac tions by hydrogen chloride. Depolymerization and hydrolysis are inititated at a considerably lower temperature in the presence of PVC, at the temperat ure of the hydrogen chloride elimination from the latter. Studying the aspe ct of high temperature decomposition it was observed that the presence of P VC severely increased the hydrogen cyanide evolution from PA-6 at 900 degre es C.