Polyamide 6 Composites with Melamine Polyphosphate and Layered Silicates: Evaluation of Flame Retardancy and Physical Properties

The potential synergy of melamine polyphosphate and layered silicates for enhancing the flame retardancy and physical properties of polyamide 6 is investigated. Through melt blending, exfoliated nanocomposites were prepared, suffering, however, from polymer degradation. In the presence of the additives, the ability of polyamide 6 to crystallize was restrained and its thermal stability was deteriorated. Nevertheless, the stiffness of the polymer was increased, yet at the expense of ductility. Apart form stiffness, the additives exerted a positive effect on the fire resistance of polyamide 6; melamine polyphosphate and layered silicates cooperated during combustion to provoke the formation of a superficial protective barrier, yielding materials of inferior flammability.