Enhanced thermal conductivity with ultralow filler loading via constructing branch-type heat transfer network

The rapid growth of modern electronic has put forward higher requirements for the design of thermal management materials. The construction of composites with low filler loading and high thermal conductivity has always been a bottleneck in the research field. Herein, the carbonized melamine sponge (MSC) with in-situ growth carbon nanotubes (CNTs) in MSC@CNTs/EP was prepared to achieve the κ ⊥ and κ ∥ of 0.51 W/(m K) and 0.48 W/(m K) at ultralow filler loading, respectively. This result showed that the expanded network structure of CNTs converted from ZIF-67 on the MSC maximized isotropic heat transfer efficiency through branch-type thermal conductive pathways. The lightweight structure endowed the skeleton with elasticity and ensured the excellent mechanical properties of the composite. The outstanding performance of the as-obtained composites demonstrates a promising prospect of tackling contemporary electronic devices thermal management issues. • Branch-type heat transfer skeleton was obtained by in-situ growth CNTs on MSC. • Extended CNTs can collect the heat flow into the thermal conductive network. • Composite owned isotropic thermal conductivity at filler loading of 0.78 wt%.