Abstract Boron nitride nanoplatelets coated with Fe3O4 nanoparticles (BNNP/Fe3O4) were fabricated via a liquid-phase exfoliation method using an ultrasonicator, and a composite was prepared by incorporating the resultant filler into an epoxy matrix. This fabrication method not only provided efficient exfoliation assisted by additional shear force from added Fe3O4 but also simultaneously made BNNP reactive toward magnetic force because of the coating of Fe3O4, which has superparamagnetic character. During the curing process, an external magnetic field was applied to vertically align the filler in the epoxy matrix, which led to an increase in thermal conductivity because of the generation of 3-dimentional thermal transport channels. The obtained thermal conductivity of the anisotropically aligned BNNP/Fe3O4 composites with a filler fraction of 20 wt% was 1.07 W/mK, which is higher than that of the raw boron nitride composites with 20 wt% filler (0.62 W/mK) because of the uniform dispersion resulting from the exfoliation and the efficient heat conduction path via filler orientation. Moreover, an enhanced storage modulus was recorded using DMA after magnetic alignment.

中文翻译：

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液相剥离法制备 Fe3O4 包覆氮化硼纳米片，用于磁性配向热增强环氧树脂复合材料

摘要 使用超声波发生器通过液相剥离法制备了包覆有 Fe3O4 纳米颗粒的氮化硼纳米片（BNNP/Fe3O4），并将所得填料掺入环氧树脂基体中制备了复合材料。这种制造方法不仅通过添加的 Fe3O4 的附加剪切力提供了有效的剥离，而且同时由于 Fe3O4 的涂层具有超顺磁性，使 BNNP 对磁力具有反应性。在固化过程中，施加外部磁场使环氧树脂基体中的填料垂直排列，由于产生了 3 维热传输通道，从而导致导热率增加。填料含量为 20 wt% 的各向异性排列的 BNNP/Fe3O4 复合材料的热导率为 1.07 W/mK，高于填料含量为 20 wt% 的原始氮化硼复合材料 (0.62 W/mK)，因为剥离产生的均匀分散和通过填料取向的有效热传导路径。此外，在磁对准后使用 DMA 记录了增强的储能模量。