Lauric Acid Based Composite Phase Change Materials Form-Stabilized with Highly Crosslinked Polymer for Thermal Energy Storage

Lauric acid (LA)-based composite phase change materials (PCMs) are prepared using a novel porous highly crosslinked polymer (HCP) framework synthesized from coumarin-3-carboxamide derived material via the Friedel-Crafts alkylation method. The preparation process of the composite PCMs occurred in three consecutive steps: synthesis of coumarin-3-carboxamide derivative material from coumarin-3-carboxylic acid; synthesis of HCP as support material, and integration of LA into the support matrix through the solvent assisted vacuum absorption process. Form-stabilization of LA with this method is rapid and easy, as well as not requiring extra purification and cleaning for composites compared to production by microencapsulation method. In addition, the advantage of HCP as a PCM support material is due to its appropriate pore morphology, and specific surface area (76.26 m² g⁻¹). The chemical structure and porous morphology of HCP matrix are detected by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analysis, respectively. According to the leakage test performed among the prepared composite PCMs, the LA/HCP-6040 composite containing 60% LA-40% HCP is determined as the composite with the highest ratio of PCM by mass without any leakage. The composite PCMs supported with HCP matrix displayed good thermal stability as a result of thermogravimetric analysis, in addition to thermal energy storage characteristics confirmed by thermal camera views.