Dual synergistic effect of a carbon/metal hybrid network on the mechanical and electromagnetic interference shielding performance in self-assembly enhanced epoxy curing networks

High performance ternary silver-coated tetra-needle-like ZnO whiskers (Ag@T-ZnO)/multi-walled carbon nanotubes (MWCNTs)/epoxy electromagnetic interference (EMI) shielding materials were prepared by a facile solvent assistant in situ polymerization (SAISP) procedure, which provides a unique deposited structure for these materials. Due to the fact that 3D Ag@T-ZnO particles are entangled by intertwined 1D MWCNTs, the incident EM wave can go through multiple interfacial reflection events in the heterogeneous interfaces between Ag@T-ZnO and intertwined MWCNTs, and 9 : 1 was determined as the appropriate mass ratio of Ag@T-ZnO and MWCNTs. The synergistic effect of the deposited carbon/metal conductive network structure and the synergy of the multidimensional hybrid fillers can provide remarkable EMI shielding effectiveness values of 86 dB and 88 dB for the EPBD-15 and EPBD-20 samples, which can still possess a high tensile strength of 72.4 MPa (compared to 56.3 MPa for the EPD-20 sample without BGE) and a Tg of 113.6 °C due to the synergistic effect of the deposited structure and the self-assembly effect of butyl glycidyl ether (BGE) soft chains in the epoxy curing network. The dual synergistic effect of carbon/metal hybrid fillers and the SAISP method can provide a new strategy for preparing structural EMI shielding composites that need high mechanical properties.