Flame Retardant Strategies and Applications of Organic Phase Change Materials: A Review

Abstract Due to their good chemical and thermal stability, high heat of melting, and suitability within the desired temperature range, organic phase change materials (PCMs) are widely used for cooling electronic devices, new energy utilization, solar thermal power generation, industrial waste heat recovery processes, and greenhouse construction. However, the flammability of organic PCMs has limited their commercial viability. In recent years, researchers have been striving to improve the flame retardancy of organic PCMs through various strategies, raising the question of which modification strategy best enhances the flame retardancy for different types of composite PCMs. Therefore, a comprehensive and timely review is needed to gain insight into the mechanism of action for flame retardant properties enhancement. This article firstly introduces the types of flame retardants and flame retardant mechanism, and briefly introduces the test methods commonly used in the laboratory for the analysis of flame retardant mechanism. Secondly, the strategies for improving the flame retardancy of organic PCMs are systematically summarized, and some scenarios for the application of organic flame‐retardant PCMs are introduced. Eventually, the challenges and future perspectives of the evolution of organic flame retardant PCMs are presented. This review is expected to provide new insights for the rational design of high flame‐retardant organic PCMs.