The fabrication and thermal conductivity of epoxy composites with 3D nanofillers of AgNWs@SiO₂&GNPs

The development of electronic makes increasing attentions focus on the high thermally conductive polymer composites. In this work, outstanding epoxy nanocomposites embedded with 3D structure fillers of silver nanowires@SiO₂ and graphite nanoplatelets are prepared successfully. Insulative SiO₂ layers coating on the surface of silver nanowires can not only provide abundant silicon hydroxyl groups to react and form strong covalent bonding with epoxy matrix and graphite nanoplatelets, minimizing the scattering of phonon and contributing to construction of thermally conductive network, but also effectively protect electrical insulation from the forming of electrical conductive pathways. An ultrahigh thermal conductivity of nanocomposites 1.092 W/m K, an enhancement of 474% to pristine epoxy, is achieved only with low filler volume fraction of 0.8 vol% silver nanowires@SiO₂ and 2.7 vol% graphite nanoplatelets, at the same time, an ultralow volume conductivity less than 1 × 10⁻⁵ S/cm is available at the frequency range 1 × 10²Hz to 1 × 10⁶Hz, which indicates strong potential in the field of electronic packaging.