Tailoring Highly Ordered Graphene Framework in Epoxy for High-Performance Polymer-Based Heat Dissipation Plates

As the power density and integration level of electronic devices increase, there are growing demands to improve the thermal conductivity of polymers for addressing the thermal management issues. On the basis of the ultrahigh intrinsic thermal conductivity, graphene has exhibited great potential as reinforcing fillers to develop polymer composites, but the resultant thermal conductivity of reported graphene-based composites is still limited. Here, an interconnected and highly ordered graphene framework (HOGF) composed of high-quality and horizontally aligned graphene sheets was developed by a porous film-templated assembly strategy, followed by a stress-induced orientation process and graphitiza-tion post-treatment. After embedding into the epoxy (EP), the HOGF/EP composite (24.7 vol %) exhibits a record-high in-plane thermal conductivity of 117 Wm−1 K−1, equivalent to ≈616 times higher than that of neat epoxy. This thermal conductivity enhancement is mainly because the HOGF as a filler
concurrently has high intrinsic thermal conductivity, relatively high density, and a highly ordered structure, constructing
superefficient phonon transport paths in the epoxy matrix. Additionally, the use of our HOGF/EP as a heat dissipation plate
was demonstrated, and it achieved 75% enhancement in practical thermal management performance compared to that of
conventional alumina for cooling the high-power LED.

随着电子设备的功率密度与集成度持续提升，解决热管理难题对聚合物导热性能的改进需求日益迫切。鉴于石墨烯具备超高本征导热性能，其作为补强填料用于制备聚合物复合材料展现出巨大潜力，但已报道的石墨烯基复合材料的导热性能仍存在局限。本研究采用多孔薄膜模板组装策略，结合应力诱导取向工艺与石墨化后处理，制备出由高品质水平取向石墨烯片层构成的互联高度有序石墨烯骨架（HOGF）。将该骨架嵌入环氧树脂（EP）基体后，体积分数为24.7 vol%的HOGF/EP复合材料面内导热系数达到117 W·m⁻¹·K⁻¹，创历史新高，约为纯环氧树脂的616倍。该导热性能提升主要源于：作为填料的HOGF兼具高本征导热系数、较高密度与高度有序的结构，在环氧树脂基体中构建了超高效的声子输运通路。此外，本研究将HOGF/EP复合材料用作散热板，用于冷却大功率LED时，其实际热管理性能相较于传统氧化铝散热板提升了75%。