Carbon fiber reinforced epoxy with enhanced electrical conductivity

The paper presents the results of electrical conductivity measurements of carbon fiber reinforced epoxy composites additionally modified by carbon microfibers (uCF) and single-wall carbon nanotubes (CNT) with different weight content. Conductivity was studied in three directions: longitudinal, diagonal and through-thickness. Carbon microfibers lead to decreasing in overall conductivity, so the higher content the higher the electrical resistivity down to –33.5% drop. Carbon nanotubes result in a sharp increase of properties for 0.1 wt %, while for higher contents they give the gradual reduction of conductivity. The changes variates from +153.1% for 0.1% to +22.1% for 0.5% of CNT. The increase of CNTs content leads to a filtering phenomenon and their agglomeration thus the epoxy interlayer thickens with a reduction of the conductivity enhancement ability.