In this paper, a shape-stabilized and flexible phase change film is prepared based on polyethylene glycol (PEG), which is stabilized by the co-operation of cellulose nanofibers (CNF) and expanded graphite (EG). The thermal conductivity of the prepared film is enhanced by boron nitride (BN). The results show that the thermal conductivity of the prepared film can reach to 10.83 W/(m·K) along the in-plane direction. The DSC results reveal that the phase change enthalpy of the film can remain 79.46 J/g and stay almost unchanged after 40 heating–cooling cycles. In addition, the leakage testing confirms that the film is form-stable under long heating time and no PEG escapes from the matrix, which might be mainly attributed to the absorption of EG and hydrogen bond barrier of CNF. Experimental results demonstrate that the prepared film can be served as the thermal management and energy storage materials for modern electronic devices.

在本文中，基于聚乙二醇 (PEG) 制备了形状稳定且柔性的相变薄膜，该薄膜通过纤维素纳米纤维 (CNF) 和膨胀石墨 (EG) 的共同作用而稳定。氮化硼 (BN) 增强了所制备薄膜的热导率。结果表明，制备的薄膜沿面内方向的热导率可达10.83 W/(m·K)。DSC 结果表明，薄膜的相变焓可以保持在 79.46 J/g，并且在 40 次加热-冷却循环后几乎保持不变。此外，泄漏测试证实薄膜在长时间加热下形状稳定，没有 PEG 从基质中逸出，这可能主要归因于 EG 的吸收和 CNF 的氢键屏障。