A solid-solid phase change material based on dynamic ion cross-linking with reprocessability at room temperature

Polyethylene glycol (PEG)-containing solid-solid phase change materials (PCMs) based on conventional chemical cross-linking avoid the leakage of the materials in the phase transition processes, but they cannot be reprocessed due to their permanent cross-linking network, giving rise to non-recyclability of the materials. In this paper, we prepared a PEG-containing solid-solid PCM based on dynamic ferric ion cross-linking, which is in solid state even at 90 ℃. Moreover, it can be reprocessed in an acidic solution at room temperature because of the dynamic ion cross-linking network. This solid-solid PCM has excellent thermal energy storage capacity and thermal stability, and its chemical structure, thermal property, crystallinity and thermal stability are all unchanged after reprocess, displaying constant performance for thermal energy storage.