Fabrication and characterization of photocrosslinked phase change materials by using conventional and terahertz spectroscopy techniques

Abstract

A series of novel photocrosslinked shape-stabilized phase change materials (PCMs) based on tetradecanol and lauric acid have been prepared by UV technique for the purpose of thermal energy storage applications. Both lauric acid and tetradecanol were reacted with glycidyl methacrylate to form acrylated structures for covalently integrate into polyurethane (PU) based UV matrix to prevent leakage problem. The heating process phase change enthalpy is measured between 9 and 77 J/g, and the freezing process phase change enthalpy is found between 1,29 and 35 J/g. All the photocrosslinked PCMs improved latent heat storage capacity in comparison with the pristine PU sample. Phase changing properties of the samples were also investigated by THz spectroscopy. Two spectral features were observed for L20 sample at 0.85 THz and 1.1 THz while no feature was observed for the other samples. The results suggest that the THz spectroscopy can be a complementary technique for characterization of the phase changing polymeric materials.