Mechanical, electrical, and electromagnetic properties of hybrid graphene/glass fiber/epoxy composite

This study presents the development of a novel three-component composite based on glass fiber/epoxy resin/graphene nanoplatelets (GNPs) aiming to obtain radar absorbing material (RAM). The composite was produced by vacuum-assisted resin transfer molding and characterized under tensile and flexural testing, reflectivity, and electrical conductivity analyses. The mechanical properties were not significantly affected by the incorporation of GNP nanofiller. However, electrical conductivity of the three-component composites increased sharply and the percolation threshold was reached with around 3 wt% GNP (surface conductivity) and 4 wt% GNP (volumetric conductivity). Furthermore, reflectivity showed excellent attenuation (up to 99.99%) in the 8.2–12.4 GHz frequency range. These attenuation levels were obtained even at low concentrations (0.1 wt%) of GNP nanofiller, indicating the possibility of producing composites with low cost and easy processing for advanced applications as RAMs.