A form-stable phase change material based on intermolecular hydrogen bonding with a high chemical recycling rate

Existing polyethylene glycol (PEG)-based phase change materials (PCMs) with recyclability are not chemically recyclable because the raw materials of the PCMs cannot be obtained after recycling. Herein, we used a facile method to prepare a PEG-based form-stable PCM (FSPCM) using mannitol as the supporting material. The intermolecular hydrogen bonding between mannitol and PEG is strong, which gives rise to a PCM solid state even at 90 °C and prevents the leakage that normally occurs with pure PEG. More importantly, the FSPCM can be chemically recycled using butyl acetate, which is a satisfactory solvent for PEG but cannot dissolve mannitol. Thus, PEG and mannitol are obtained, with recycling rates greater than 90% for each. Additionally, there are high latent heat values for this PEG-based FSPCM, as well as excellent thermal stability and thermal reliability, suggesting the remarkable ability for thermal energy storage and thermal management.