Electrical and thermal properties of silicone rubber composites filled with Cu-coated carbon fibres and functional carbon nanotubes

The thermal and electrical conductivities of SR composites containing Cu-CFs and f-MWNTs were studied. The Cu-CFs and f-MWNTs were prepared by chemical deposition and the coupling method, respectively. Both the fillers were characterised by FT-IR, XRD and SEM and the results showed that the Cu layers were deposited on the surface of the CFs and the MWNTs were successfully modified. In addition, the results of thermal and electrical conductivities for SR composites showed that the hybrid fillers system exhibited a better enhancement on thermal and electrical conductivities for SR composites than the single filler system. The maximum thermal conductivity and the least volume resistivity of SR/Cu-CFs/f-MWNTs composites could reach 3.86 W (m K)⁻¹ and 3.5 × 10³ Ω cm, respectively. Based on the experimental results, we recognised the improvement of intrinsical thermal and electrical conductivities of CFs and the good dispersion of MWNTs contributed to the formation of densified 3D conducting networks. Thus, the hybrid fillers system could synergistically enhance the thermal and electrical conductivities of SR composites. We believe, this study could provide an effective way for the design of high conductive polymer composites.