On the thermal performance of a novel PCM nanocapsule: The effect of core/shell

Abstract To control the particle size distribution of nanocapsules, the nanoencapsulation of paraffin wax with polyurethane (PU) is performed via the interfacial polymerization. For this purpose, the spherical and solid nanoparticles of paraffin wax are first prepared using the novel semi solvent-non solvent method in the presence of sodium dodecyl sulfate (SDS). Then, the obtained nanoparticles are encapsulated with a polyurethane shell, based on novolac and toluene 2,4-diisocyanate (TDI). The chemical structure, thermal performance, microstructure and morphology of nanocapsules are investigated. The FESEM results confirm the formation of spherical paraffin wax nanoparticles with a particle size distribution of 25–185 nm. The effect of core/shell mass ratio on the thermal properties of the obtained nanocapsules was studied. According to DSC results, the energy storage efficiency and the energy storage capacity of adequate nanocapsules are 80.2% and 97.5%, respectively. The successful nanoencapsulation of paraffin wax with a polyurethane-based shell is confirmed by TEM analysis. Moreover, the thermal cycling tests indicate the high thermal resistance of prepared core-shell system, even after 100 heating/cooling cycles, and have an excellent potential for energy storage and release performance of the system.