Synthesis and Characterization of Phase Change Materials for Thermal Energy Storage Applications /

Abstract

Eutectic phase change materials (EPCMs) based on fatty acids-polyethylene glycol are developed for low temperature thermal energy storage application. Four distinct eutectic PCMs (PA-PEG2K, PA-PEG4K, SA-PEG2K, and SA-PEG4K) are prepared through melt blending followed by ultra sonication. Thermal properties such as melting temperature, latent heat, and eutectic composition of the PCMs are calculated using the Schrader equation. The chemical structure of the prepared eutectic PCMs is analyzed using Fourier Transform Infrared Spectroscopy. Thermal properties are also experimentally determined using a Differential Scanning Calorimeter and the prepared eutectic PCMs exhibit melting temperature ranging from 46.4°C to 54.7°C. The latent heat of prepared eutectic PCMs falls between 185.89 J/g and 188.33 J/g, and specific heat capacity in liquidus ranges from 2.2 J·g-1·°C-1to 2.4 J·g-1·°C-1 whereas, specific heat capacity in solidus ranges from 1.6 J·g-1·°C-1 to 1.8 J·g-1·°C-1. It is evident from the TGA that these developed fatty acid polyethylene glycols based binary eutectic combinations exhibit promising thermal stability. However, the results from DTC indicated that the thermal conductivity of EPCMS lies in the range of 0.347W/mK to 0.423W/mK. These eutectic PCMs have promising characteristics for low to moderate temperature thermal energy storage applications such as solar thermal space heating and domestic water heating systems.