Construction of conductive three-dimensional structure by low content of silver nanowires and its application in epoxy resin

A conductive macro-network was fabricated by dip-coating silver nanowires (AgNWs) on the polyurethane (PU) sponge skeleton and a semi-conductive epoxy nanocomposite was obtained. The resulting nanostructures exhibit an effective pathway to achieve low electrical percolation threshold for a scalable 3D conductive network with low loading of fillers. The epoxy composites filled with conductive 3D foams show the enhanced thermal stability, glass transition temperature and mechanical properties. The volume resistivity of the obtained epoxy/PU@AgNWs composites decreases from 1.1 × 10 17 to 1.9 × 10 5 Ω cm with ultralow AgNWs loading of ~ 0.14 vol%, and meanwhile thermal conductivity is improved by 45% at 0.282 W/mK compared to neat epoxy resin. This method might be a scalable and effective way for the applications in the high-performance semi-conductive engineering devices.