Pentaerythritol with alumina nano additives for thermal energy storage applications

Abstract

Pentaerythritol is a poly alcohol with high solid–solid phase change enthalpy that makes it suited for thermal energy storage applications. At solid–solid phase transition temperature, pentaerythritol change from body centered tetrahedral molecular structure into a homogeneous face-centered cubic crystalline structure accompanied with the absorption of the hydrogen bond energy. The present work investigates the effect of adding alumina (Al2O3) nanoparticles to pentaerythritol on thermal and chemical stability by performing thermal cycling test. Dispersion stability and aggregation of nanoparticles during thermal cycling were studied with FESEM and EDX analysis. The thermal and chemical stability of pentaerythritol samples added with alumina nanoparticles in the weight proportions 0.1%, 0.5% and 1% were tested using the characterization methods such as TGA, DSC and FTIR. The change in the specific heat and thermal conductivity of pentaerythritol was studied by the T-history method. The experimental results showed good thermal and chemical stability for alumina enhanced pentaerythritol subjected to 100 thermal cycles along with a negligible change in specific heat and thermal conductivity values. Non-isothermal crystallization kinetics of the PE added with alumina nanoparticles were also studied in this experimental work.