Micro/nano encapsulated n-tetracosane and n-octadecane eutectic mixture with polystyrene shell for low-temperature latent heat thermal energy storage applications

A series of micro/nano capsules of PS/(C24-C18) eutectic mixture were synthesized using emulsion polymerization method. The synthesized micro/nano capsules were characterized chemically using FT-IR, POM, SEM and PSD techniques. The SEM and PSD results proved that the surfaces of the capsules had not completely spherical appearances and bimodal particle size distributions changed within 0.01-115 μm. The thermal characteristics measured using DSC and TGA techniques indicated that the capsules containing highest amount of the eutectic mixture had a melting temperature of 25.96 °C, latent heat of 156.39 J g−1 and high thermal durability. The thermal cycling test confirmed that the PS/(C24-C18) micro/nano capsules with 1:2 shell/core ratio had good thermal reliability. Furthermore, the synthesized PS/(C24-C18)(1:2) micro/nano capsules had a considerable high thermal conductivity and reversible phase change character.162