Flame retardant and leaking preventable phase change materials for thermal energy storage and thermal regulation

Abstract Phase change materials (PCMs) possess great potential in thermal energy storage and thermoregulation scopes. However, liquid leaking and high flammability restricts their practical applications seriously. In this work, an innovative and facile chelation-deposition strategy is proposed to prepare flame retardant PCMs (FRPCMs) with 1-octadecane as the phase change substance and bio-based magnesium phytate (PAMg) as the flame retardant shell. In this way, the liquid leaking and flammability issues are addressed simultaneously. We have undertaken a comprehensive study on the structure and properties of the FRPCMs via various tests. It is confirmed that the 1-octadecanol is successfully microencapsulated by the PAMg shell and its crystal structure is not affected. The thermal storage capacity is evaluated with differential scanning calorimetry (DSC) and the latent heat is ranged from 117 to 158 J/g. Limited oxygen index (LOI) and cone calorimeter are performed to assess the flame retardancy of FRPCMs. The LOI value of the epoxy resin/FRPCM composites is increased from 18.5 to 21.6 and the total heat release (THR) is reduced by 39.5% with the addition of FRPCMs particles. The FRPCMs are proved to possess good leaking prevention performance at 90 °C (higher that the melting point of 1-octadecanol). Furthermore, the long term thermal reliability, thermal regulation, leaking prevention and corrosive characteristics of FRPCMs are characterized.