Polyamides from lactams by centrifugal molding via anionic ring-opening polymerization

This paper deals with a study of some properties of the polymers obtained by centrifugal molding via activated anionic ring-opening polymerization of ϵ-caprolactam and copolymerization of ϵ-caprolactam with laurolactam. Ethyl magnesium bromide, as initiator and N-benzoyl ϵ-caprolactam and N,N′-isophthaloyl-bis-ϵ-caprolactam, as activators were used. The initial mold temperature (initial polymerization temperature) was kept constant at 160°C. Our experimental data demonstrated that the degree of crystallinity depends on the activator type and concentration. The incorporation of laurolactam into nylon 6 chain depresses both in the degree of crystallinity and the melting temperature of nylon 6/12 copolymers. The notched Izod impact strength of the copolymers increased as the laurolactam content was increased, while the flexural modulus and the water absorption decreased.