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.

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.

Based on the fast growth of the device performance, there has been an increasing demand for handling the issue of thermal management in electronic equipments. Therefore, it is of great significance to improve the thermal conductivity of thermoplastics, which are commonly used in electronic components. However, the difficulty of graphene dispersion and strong interfacial phonon scattering restrict the heat dissipation performance of graphene/thermoplastic composites, especially in the case of polypropylene (PP) or polyethylene (PE). Here, we propose a single-step and versatile approach to fabricate graphene/thermoplastic composites with a remarkable thermal conductivity enhancement. The composites were prepared by coating graphene on polymer powder first, followed by hot pressing. As a result, an interconnected graphene framework can be developed in the thermoplastic matrix, leading to significant heat transfer enhancement of the composites. At a 10 wt% graphene content, the thermal conductivity reaches 1.84, 1.53, 1.43, and 1.47 W m⁻¹ K⁻¹ for PE, PP, PVA (poly(vinyl alcohol)), and PVDF (poly(vinylidene fluoride)) composites, respectively. Our finding provides a path to develop a variety of highly thermally conductive thermoplastic composites for use in heat dissipation and other thermal applications.