Hexagonal boron nitrides (h-BNs) have received much attention as thermally conductive fillers because of their high thermal conductivity. However, their high aspect ratio hampers the realization of high filler loading by dramatically increasing viscosity and deteriorating the processabilty of the h-BN composites. To address this issue, an epoxyorganosiloxane with the viscosity of 250 mPa·s was used to maximize h-BN loading in composites in this study. Although the BN-50 composite containing 50 wt% of h-BN achieved high in-plane thermal conductivity (5.25 W/m·K), its use was limited because of its low through-plane thermal conductivity (1.35 W/m·K) and high viscosity. To overcome this, spherical aluminum oxides (s-AOs) were incorporated into the h-BN composite with 40 wt% fillers. This increased the through-plane thermal conductivity of the h-BN/AO hybrid composites up to 2.47 W/m·K. Moreover, thanks to the spherical shape of AOs, the viscosity of the h-BN/AO hybrid composites was lower than that of the BN-50 composite despite higher filler loading.

六方氮化硼（h-BNs）作为导热填料因其高导热性而备受关注。然而，它们的高纵横比会显着增加粘度并降低 h-BN 复合材料的加工性能，从而阻碍了高填料负载的实现。为了解决这个问题，本研究中使用粘度为 250 mPa·s 的环氧有机硅氧烷来最大化复合材料中的 h-BN 负载。虽然含有 50 wt% h-BN 的 BN-50 复合材料实现了高面内热导率（5.25 W/m·K），但由于其较低的面内热导率（1.35 W/m·K），其应用受到限制。 ) 和高粘度。为了克服这个问题，将球形氧化铝（s-AOs）加入到 h-BN 复合材料中，填料含量为 40%。这将 h-BN/AO 混合复合材料的平面热导率提高到 2.47 W/m·K。此外，由于 AO 的球形，h-BN/AO 混合复合材料的粘度低于 BN-50 复合材料的粘度，尽管填料负载量更高。