Multifunctional graphene/POSS epoxy resin tailored for aircraft lightning strike protection

This paper presents a first successful attempt to obtain a conductivity mapping at nanoscale level of a new multifunctional fire retardant graphene/polyhedral oligomeric silsesquioxane (POSS) epoxy resin using Tunneling Atomic Force Microscopy (TUNA) that is a very sensitive mode by which ultra-low currents ranging from 80 fA to 120 pA can be measured. The multifunctional material, specifically designed to meet structural aeronautical requirements, such as suitable thermal stability, fire resistance, mechanical performance and electrical conductivity, has proven to be a promising candidate in the field of aeronautic and aerospace composites. The results also highlight the great potentiality of TUNA technique to analyze conductive networks at nanodomain level. Through simultaneous topographic and current images acquisition, this technique enables a direct correlation of local topography with electrical properties of the nanofiller based samples. The intrinsic electrical conductivity of the manufactured polymeric systems allows TUNA measurements without using electrical conductive paint, which is usually employed for polymeric systems to ensure effective electrical contacts to the ground.