Here, we report a facile method to delaminate MXene (Ti₃C₂T_x) and prepare poly(vinylidene fluoride) (PVDF)/MXene composites by solution blending. Compared with neat PVDF, the PVDF composites with varying content of MXene (0–5 wt%) showed an enhancement in the PVDF thermal conductivity. In particular, when a loading of 5 wt% was attained, the thermal conductivity was increased to 0.363 W mK⁻¹, an approximate 1-fold enhancement compared with that of neat PVDF. In addition, MXene also exhibited a better performance in enhancing the thermal dynamic mechanical properties of PVDF. For instance, PVDF composites with only 5 wt% MXene exhibited a storage modulus as high as 7501 MPa, corresponding to a 64% enhancement compared with that of neat PVDF. In light of the excellent thermal properties of the PVDF/MXene composites, they can be expected to have a wide range of potential applications in thermal interfacial materials and structural components.

As a new member of the group of promising 2D materials, MXene shows the advantages including metallic conductivity, high charge carrier mobility, tunable band gap, flexibility and diverse surface chemistry, favorable optical and mechanical properties. These unique properties have drawn huge attention, and research on MXene has been intensively conducted and innovative applications have been reported in various fields. At the same time, MXene/polymer nanocomposites have been developed, and many amazing results have been reported. However, overviews of the status and progress in this field are rare. In this paper, first, the preparation method and technical route of MXene/polymer nanocomposites are reviewed. It is found that solution mixing and in situ polymerization are the main preparation methods of the nanocomposites. Second, the properties of the composites are presented. It is shown that MXene can effectively improve the electrical, mechanical, and thermal characteristics of polymers. Then, innovative applications and representative results of the composites in the biomedical, sensing, energy, electromagnetic protection, and other fields are summarized. Finally, the development prospects and key challenges of the composites are listed concisely.

Graphene is usually embedded into polymer matrices for the development of thermally conductive composites, preferably forming an interconnected and anisotropic framework. Currently, the directional self‐assembly of exfoliated graphene sheets is demonstrated to be the most effective way to synthesize anisotropic graphene frameworks. However, achieving a thermal conductivity enhancement (TCE) over 1500% with per 1 vol% graphene content in polymer matrices remains challenging, due to the high junction thermal resistance between the adjacent graphene sheets within the self‐assembled graphene framework. Here, a multiscale structural modulation strategy for obtaining highly ordered structure of graphene framework and simultaneously reducing the junction thermal resistance is demonstrated. The resultant anisotropic framework contributes to the polymer composites with a record‐high thermal conductivity of 56.8–62.4 W m⁻¹ K⁻¹ at the graphene loading of ≈13.3 vol%, giving an ultrahigh TCE per 1 vol% graphene over 2400%. Furthermore, thermal energy management applications of the composites as phase change materials for solar‐thermal energy conversion and as thermal interface materials for electronic device cooling are demonstrated. The finding provides valuable guidance for designing high‐performance thermally conductive composites and raises their possibility for practical use in thermal energy storage and thermal management of electronics.

3DSG incorporated into a polyimide matrix greatly enhanced its thermal conductivity (up to 2.63 W m⁻¹ K⁻¹), approximately a 10-fold enhancement in comparison with that of neat polyimide.