New Routes of Valorization of Recycled and Bio-sourced Polyamides with a Low Toxicity Process

International audienceThe aim of the present work is the development of new materials from renewable resources mixed with recycled polymers. The article focuses on the studies of (PAX/PA6) and (PAX/PA66) blends using three coupling agents: PBO, DGEBA, Lotader 3210. Blends of various compositions were prepared in a corotating twin-screw extruder. PA6 (PA66) acts as the polymer matrix and PAX as the dispersed phase. The morphology of the compatibilized PAX/PA6/DGEBA (25/75) and PAX/PA66/DGEBA (25/75) blends shows lower diameters and a decrease in the size of the dispersed PAX particles. The addition of DGEBA not only leads to a much finer phase domain size, but also improves the interphase between PA6 (PA66) and PAX phases. Moreover, rheological analysis indicates that the increase in viscosity was much more pronounced with DGEBA than with Lotader 3210 and PBO especially for PAX/PA6 (25/75) and PAX/PA66 (25/75) blends, which can be indicative of good reactivity of the terminal −NH2 groups of PA6 or PA66 with the epoxy groups of DGEBA. The improvement of interphase between phases induced an increase in tensile properties. VOC from PA66 were recovered and found not to modify the viability of human macrophages, which can be a sign of a low toxicity of the process