components. Polymeric phase change composites exhibit immense potential applications in energy conversion, thermal management, smart clothing, and shape memory device. High‐performance and multifunctional phase change composites as an advanced TES technique are bound to play an increasingly important role in energy storage‐related applications.
Although high‐performance polymeric phase change composites have been greatly developed, many technologies are not mature enough to achieve mass production. There is a long way to go from the laboratory to the factory, in particular high‐efficiency 3D porous macroarchitectures. Of note, the introduction of functionality is at the expense of energy storage density, but high energy storage density is the intrinsic essence of PCMs. It is unwise to ignore the original intention when developing new polymeric phase change composites. Therefore, it is of significance to optimize the structural design and processing technology to improve the utilization efficiency of functional materials. Moreover, the effect of nanomaterials and nano/microstructures on the phase change behaviors needs to be further clarified. Accordingly, green, safety, efficiency, and cost, these timeless pursuits, are still the concerns. More attention is well‐advised to be paid to sustainable, flexible, and intelligent polymeric phase change composites in the future. (i) For the perspective of polymeric supporting component, biodegradable materials are considered as plausible alternatives, including nanomaterials represented by nanocellulose and biomasses like porous wood. (ii) With the emergence of Internet of Things (IoT), flexible devices for wearable applications are becoming research priorities, and flexible phase change energy storage composites are an indispensable part. (iii) Breaking through existing application scenarios, polymeric phase change composites are likely to be more intelligent in the future, such as multiresponsive materials, self‐adaptive devices, infrared stealth systems, advanced thermotherapy, smart drug delivery, and so on.
Acknowledgments
This work is financially supported by the National Natural Science Foundation of China (51873126 and 51721091).
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