Study on Microcapsules with Chitosan‐Based Polyurethane/SiO ₂ Composite Shells for Encapsulating Phase Change Material

The development of green energy is an inevitable choice for coping with climate change and achieve sustainable development. Phase change material (PCM) is a kind of green and clean energy storage material, but the application of phase change microcapsules (PCMs) is restricted by their low heat conductivity. Therefore, the PCMs with chitosan‐based polyurethane/SiO 2 composite shell (SiO 2 @PCMs) are fabricated via interfacial polymerization in conjunction with tetraethyl orthosilicate hydrolysis. Lauryl alcohol, which may also be utilized as PCM and encapsulated in microcapsules, is added to the core materials to consume unreacted 4,4′‐dicyclohexylmethane diisocyanate (HMDI) in order to address the possible issue of HMDI residue (which has a certain level of toxicity). The morphology and thermal properties of SiO 2 @PCMs are systematically investigated. The experimental results show that the thermal conductivity of SiO 2 @PCMs is 18.8% higher than that of PCMs. Hence, the application of the prepared SiO 2 @PCMs in energy storage has great potential in the future.