Influence of electroless Ni-plated MWCNTs on thermal conductivity and fracture toughness of MWCNTs/Al₂O₃/epoxy composites

In this work, the effect of electroless Ni-plating of multi-walled carbon nanotubes (MWCNTs) on thermal conductivity and fracture toughness properties of MWCNTs/Al₂O₃/epoxy composites was investigated. The surface properties of the Ni-plated MWCNTs were determined by scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), and X-ray diffraction (XRD) analyses. Thermal conductivity was tested using a thermal conductivity measuring system. The fracture toughness of the composites was carried out through the critical stress intensity factor (K_IC) measurement. As a result, the electroless Ni-plated MWCNTs led to a significant change of surface characteristics of the MWCNTs. Thermal conductivity and fracture toughness of the MWCNTs/Al₂O₃/epoxy composites were greater than those of non-treated ones. These results were probably due to the improvement of intermolecular interaction between the Ni-MWCNTs and the matrix resins.