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With the development of electronic devices such as integrated circuits toward the continual increase in power density and consumption, the efficient heat dissipation and low thermal expansion of materials become one of the most important issue. However, conventional polymers have the problem of poor thermal dissipation performance, which hinder application for electronic devices. In this work, the two-dimensional material, MXene (Ti 3 C 2 ), is used as the reinforcement additive to optimize the thermal properties of polymers. We reported the preparation of multilayer Ti 3 C 2 MXene by HF etching method and obtained few-layer Ti 3 C 2 MXene by simple ultrasonication. Meanwhile, Ti 3 C 2 /epoxy composites were prepared by a solution blending method. The results show that the thermal properties of the composites are improved in comparison with the neat epoxy. Thermal conductivity value (0.587 W/mK) of epoxy composite with only 1.0 wt% Ti 3 C 2 MXene fillers, is increased by 141.3% compared with that of neat epoxy. In addition, the composite presents an increased glass transition temperature, high thermal stability and lower coefficient of thermal expansion. This work is of great significance for the research of high-performance composite materials.

A strategy was reported to prepare boron nitride nanosheets (BNNSs) by a molten hydroxide assisted liquid exfoliation from hexagonal boron nitride (h-BN) powder. BNNSs with an average thickness of 3 nm were obtained by a facile, low-cost, and scalable exfoliation method. Highly thermally conductive polyimide (PI) composite films with BNNSs filler were prepared by solution-casting process. The in-plane thermal conductivity of PI composite films with 7 wt% BNNSs is up to 2.95 W/mK, which increased by 1,080% compared to the neat PI. In contrast, the out-of plane thermal conductivity of the composites is 0.44 W/mK, with an increase by only 76%. The high anisotropy of thermal conductivity was verified to be due to the high alignment of the BNNSs. The PI/BNNSs composite films are attractive for the thermal management applications in the field of next-generation electronic devices.

Efficient heat dissipation is a prerequisite for further improving the integration of devices. However, the polymer composites are not satisfying heat dissipation. For that reason, high-thermal-transport channels were manufactured by the direct freezing method and boron nitride nanosheets (BNNS) were further welded by carbonization. Composites with high thermal conductivity (7.46 W m −1 K −1 ) were obtained by immersion in poly-(dimethylsiloxane) (PDMS). Thermal conductivity enhancement of composites reached about 3900% at 15.8 vol % loading of BNNS. Besides, the composites maintained the structural flexibility of PDMS and allowed repeated bending and twisting. In addition, the PDMS composites exhibited excellent antistatic properties because of a conductive network formed by residual carbon. Therefore, dust could be avoided and the surface kept clean. This provides a better choice for thermal management materials and meets the antistatic requirements of the devices.

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