Microencapsulation of n-hexadecane as phase change material by suspension polymerization

In this study, suspension polymerization is described to fabricate microcapsules containing n-hexadecane as phase change material. In the suspension polymerization, casein is employed as emulsifier and stabilizer instead of synthetic surfactant. Microcapsules with polystyrene as shell and n-hexadecane as core have an average diameter of 3 similar to 15 mu m and the size distribution are narrow. Thermal properties are investigated by differential scanning calorimetry ( DSC) showing that the microcapsules can store and release an amount of latent heat over a temperature range nearing the melting point of pure n-hexadecane. The latent heat of fusion of microencapsulated n-hexadecane decreases after microencapsulation. The melting point of microencapsulated n-hexadecane is near but higher than that of pure n-hexadecane, and the polymerization time has little effect on the melting point.