Surface modification for improving interfacial, mechanical and thermal performance characteristics in epoxy composites: Electroless nickel enhancement of dendritic copper particle-reinforced epoxy

While studies on the incorporation of metal particles into the epoxy matrix are quite common, this research introduces a novel approach by incorporating electroless Ni-coated Cu particles with functional features into the epoxy matrix. Thus, it presents an innovative investigation of epoxy composites with enhanced both thermal and mechanical properties. Therefore, three samples of pure epoxy, dendritic Cu particle reinforced (20 wt%), and electroless Ni-coated dendritic Cu particle reinforced (20 wt%) epoxy composites were fabricated by mixing followed by casting into the mold. The epoxy and composite specimens underwent phase analysis through XRD, and morphological examinations were conducted using SEM equipped with an EDS analyzer, respectively. The hardness, tensile, and bending tests were conducted for mechanical characterization. To evaluate the thermal properties, DSC and TGA tests were employed to assess the impact of the Cu and the electroless Ni-coated Cu particles on the thermal stability of the composites. The mechanical analysis results showed that the pure epoxy sample had tensile and flexural strengths of 23.2 MPa and 43 MPa, respectively. These values increased significantly by 90 % and 311 % in the presence of Ni-coated dendritic Cu particles, reaching 54 MPa and 177 MPa, respectively. Thermal analysis results indicated that the Tg increased with the incorporation of dendritic Cu particles and Ni-coated dendritic Cu particles. Furthermore, the highest thermal conductivity was observed in the Cu-reinforced composites.