Improving thermal conductivity of ethylene propylene diene monomer/paraffin/expanded graphite shape-stabilized phase change materials with great thermal management potential via green steam explosion

For thermal management of phase change materials (PCMs), the main concerns are liquid leakage and low thermal conductivity. Here, via a green steam explosion method with the assistance of pure water, we fabricated a series of ethylene propylene diene monomer/paraffin wax/expanded graphite (EPDM/PW/EG) shape-stabilized PCMs (SSPCMs) with enhanced thermal conductivity resulting from better EG dispersion. Specifically, the steam explosion processed EPDM/PW/EG SSPCM with 9.0 wt.% EG obtains 448.2% thermal conductivity to that of EPDM/PW; the single steam explosion process enhanced the thermal conductivity by 27.4% compared the steam explosion processed and unprocessed EPDM/PW/EG SSPCM with same EG fraction (9.0 wt.%). With improved thermal conductivity, the obtained SSPCMs could absorb the heat faster in heating process and dissipate the heat quicker in the cooling process, exhibiting enhanced thermal management properties. In addition, steam explosion processed SSPCMs simultaneously exhibit improved shape recovery properties, revealing more possibility to fit into the installation space. Coupled with reusability, shape stability, flexibility, and excellent thermal properties, the obtained SSPCMs were proved to be promising candidates for thermal management. Graphical abstract The SSPCMs with enhanced thermal conductivity were developed by steam explosion method and possessed excellent thermal management properties.