Effect of SiO2 Nanoparticles on Thermal Properties of Polyaniline/ Palmitic Acid Composite as an Energy Storage System

Phase Change Materials (PCMs) can be used as thermal energy storage systems in the form of latent heat. These materials are commonly enclosed in a suitable container, in order to prevent leakage of the molten PCM into the surrounding environment. In this study, palmitic acid and polyaniline were used as PCM and polymeric shell, respectively, to prepare a form stable composite. SiO2 nanoparticle was added to the composite to improve the thermal characteristics of the composite. The structure and morphology of the prepared form stable nanocomposite were investigated by Fourier Transform InfraRed (FT-IR) spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), and X-Ray Diffract meter (XRD) tests. It was found that the synthesized nanocomposite was fabricated in the form of relatively smooth and compact spherical particles with a size of about 500 nm. Thermal properties of the prepared nanocomposite containing different concentrations of SiO2 nanoparticles were determined using Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA) tests. It was found that the melting temperature and thermal conductivity of the polyaniline/palmitic acid composite increased by about 16% and 62%, respectively, when combined with 2 wt.% SiO2 nanoparticles. The obtained results revealed that the polyaniline/palmitic acid/2 wt.% SiO2 nanocomposite can be considered a suitable option for thermal energy storage applications.