Mechanical, thermal, and flammability properties of polyamide-6 reinforced with a combination of carbon nanotubes and titanium dioxide for under-the-hood applications.

The current study aims to explore the tensile fracture mechanism and thermo-mechanical efficiency of polyamide-6 (PA6) reinforced with titanium dioxide (TiO₂) and multiwalled carbon nanotubes (MWCNTs). The uniform dispersion of the MWCNTs and appreciable interfacing between PA6, TiO₂, and MWCNTs were revealed in the fractography figures. The crystallization temperature and degree of crystallinity have been enhanced by the addition of nanoparticles to the PA6 matrix. Young's modulus, tensile strength, and Charpy impact strength improved proportionally concerning reinforcement content. The essential work of fracture (EWF) method was applied to evaluate the toughening and fracture behavior of PA6 hybrid systems. Considerable improvement (+60.6%) in the EWF of PA6–TiO₂–MWCNT nanocomposites was observed at 4 wt.% CNT and 2 wt.% TiO₂. Limiting oxygen index (LOI) findings demonstrate that a polymer with a combination containing titanium dioxide and multiwalled carbon nanotubes has a highly substantial retardant influence. As a result, the TiO₂–CNT combination acts as a synergist filler, offering versatile PA6 composite products. [ABSTRACT FROM AUTHOR]