Fabrication and thermal characterization of kaolin-based composite phase change materials for latent heat storage in buildings

In this study, the surface morphology, compatibility, maximum PCM ratio, phase change-energy storage properties, thermal endurance, thermal conductivity and heat storage performances of the prepared kaolin (K)-based building composite phase change materials (Kb-CPCMs) were investigated by using microscopy, spectroscopy, calorimetry and thermal methods. The Kb-CPCMs, including capric acid, PEG600, and heptadecane have a melting temperature of 30.71 °C, 5.16 °C and 22.08 °C and a latent heat of 27.23, 32.80 and 34.63 J/g, respectively. The thermal reliability of the Kb-CPCMs slightly changed after 1000 heating-cooling cycling. The heat storage rates of Kb-CPCMs were considerably increased by addition of EG (5 wt%). All the prepared Kb-CPCMs have good thermal energy storage (TES) function for HVAC applications in building envelopes because of their good thermal energy storage properties, reusability performance and enhanced thermal conductivity.