Microcellular epoxy/graphene nanocomposites with outstanding electromagnetic interference shielding and mechanical performance by overcoming nanofiller loading/dispersion dichotomy

With the rapid evolvement of wireless communication technologies, ever increasing needs to prevent electromagnetic waves (EMWs) pollution have urged development lightweight materials with excellent interference (EMI) shielding property. However, achieving desired EMI performance often requires high loadings conductive nanofillers, like graphene, which poses challenges control nanoparticle dispersion and mechanical nanocomposite. Herein, we demonstrate a method fabricate highly-loaded (>30 wt%) graphene in microcellular epoxy nanocomposites, successfully overcoming long-lasting dichotomy field nanocomposites filler loading dispersion. By utilizing supercritical CO 2 foaming method, modified thermosetting epoxy-based nanocomposite was foamed multiple interfaces tunable cells. In addition, rearrangement nanofillers during process is favorable for more intense network, leading enhanced EMWs attenuation by repeated reflections absorptions. An optimal combination electrical conductivity (314 S m ?1 ), effectiveness (86.6 dB 156.3 dB/(g/cm 3 )), compressive strength (27.4 MPa) density (0.55 g cm ?3 ) has been achieved 32.26 wt % content. This versatile opens up an easy route structural foams nanofiller contents, could be used many applications such as electronics, robotics, aircrafts. • A strategy prepare m-EP/rGO wt% rGO uniform Controlled foamability scCO process. Excellent (3.14 × 10 S/m) SE (SE T = 86.6 dB) from foam.