Studies on preparation and properties of the multi-walled carbon nanotubes (MWNTs)/epoxy nanocomposites

► We use the modified MWNTs as fillers fabricated epoxy nanocomposites. ► The mechanical, thermal and dielectric properties of nanocomposites are measured. ► The nanocomposites exhibited better mechanical and dielectric properties. The MWNTs were coated with polyaniline (PANI) by in situ chemical oxidation polymerization method. FTIR spectroscopy, scanning electron microscope (SEM) and X-ray diffraction (XRD) indicated that the MWNTs were coated with PANI. The MWNTs/epoxy nanocomposites were fabricated by using the solution blending method. Differential scanning calorimetry (DSC), tensile testing, HP 4294A impedance analyzer and SEM were used to investigate the properties of the nanocomposites. The results showed that the modified carbon nanotubes were well dispersed in the polymer matrix. The nanocomposites have enhancements in mechanical, thermal and dielectric properties compare with the neat epoxy resin. The nanocomposites were proven to be a good polymer dielectric material.