Epoxy-based vinyl ester nanocomposites filled with graphite nanoplatelets (GNPs) are developed for applications as radar absorbing materials at radio frequency. The main scope of this study is the scale-up of the fabrication process of nanocomposites with improved mechanical and electromagnetic properties, for large-scale aeronautical application. To this purpose the use of commercially available GNP-powders is investigated. The percolation curve of the nanocomposite is derived from measurements of the DC conductivity for increasing filler concentration. DMA analyses are performed in order to investigate the mechanical properties of the material. The obtained results demonstrate a good correlation between the electrical and mechanical properties of the produced material.