Erythritol-based phase change materials: Supercooling enhancement and adaptive heat-triggered release for extreme environmental thermal applications

Phase change materials (PCMs) have demonstrated considerable promise in the realm of thermal storage applications in low-temperature environments. However, conventional PCMs encounter challenges in terms of heat exchange with the environment and are susceptible to spontaneous crystallization and exotherm, resulting in inadequate thermal storage stability. This study focuses on erythritol (ery), a low to medium temperature PCM with high latent heat and substantial supercooling capacity. A novel approach is proposed, utilizing the -OH groups within ery to form dynamic hydrogen bonds with the C O groups of polyvinylpyrrolidone (PVP). This interaction aims to enhance ery's supercooling capacity and achieve long-term thermal storage in low-temperature environments. The introduction of PVP effectively inhibits the spontaneous crystallization of ery at low temperatures, while concurrently significantly enhancing its supercooling degree. This enhancement is achieved by increasing the viscosity and spatial potential resistance of the system, as well as by forming hydrogen bonds. The experimental findings demonstrate that the ery-pvp composites demonstrates remarkable long-term stability at temperatures as low as 0 °C. Over a period of 3 months during low-temperature thermal storage, no exothermic phenomenon was observed. Concurrently, there is evidence that adaptive thermally triggered cold crystallization in ery-pvp can be realized in those environments above 0 °C or triggered by human body temperature. This finding underscores the composite's exceptional stability and adaptive, controllable exothermic properties, positioning it as a promising long-term heat storage medium in low-temperature environments. • Polymer modification enables exceptional supercooling in erythritol-based PCMs via H-bonding. • Achieved ultra-stable supercooled thermal storage over 3 months at −20 °C • Demonstrated adaptive heat-triggered cold crystallization from the supercooled state • Human body temperature effectively triggers energy release for passive heating. • Novel strategy offers promise for smart, long-term TES in extreme cold.