Electrical conductivity and electromagnetic shielding performance of glass fiber-reinforced epoxy composites with multiwalled carbon nanotube buckypaper interlayer

Glass fiber/epoxy-reinforced multi-walled carbon nanotube buckypaper composites (GF/EP/BP) were fabricated by hot compression molding process to evaluate its electromagnetic interference (EMI) shielding efficiency (SE) in the X-band (8.2–12.4 GHz) frequency range. Scanning electron microscopy (SEM) revealed a porous structure for the CNT film and good overall quality of the GF/EP/BP composite with no apparent voids or defects associated to the lamination process. The electrical conductivity of the CNT film was around 996 S/m and its incorporation at the mid-plane of the laminates had no influence in the electrical conduction of the composites. EMI SE results of about 18 dB were obtained for the 3 mm nanostructured composite over the X-band so that the dielectric properties, the total electrical conductivity, and the interfacial polarization phenomenon had great importance in the EMI shielding properties of the manufactured composites.