Development, Thermal Properties, and Reliability Testing of Eutectic Polyethylene Glycol as Phase Change Materials for Thermal Energy Storage Applications

The present work outlines the development of eutectic phase change material in different mass fraction ratio and determining its thermal properties. The eutectic mixture was prepared by using polyethylene glycol (PEG) of atomic weight 10 000 and 6000. The eutectic was prepared by using single-step stirring and blending methods. Phase transition temperature and fusion latent heat were evaluated by differential scanning calorimetry (DSC) technique. The variation in chemical composition of the eutectics was analyzed by using Fourier transform infrared spectroscopy (FT-IR) analysis. The sample was prepared in the mass fraction ratio difference of 10%. The result shows that the sample containing PEG 6000 and PEG 10 000 in the ratio of 60:40 possesses maximum latent heat of fusion which is 194.52 J center dot g(-1). In order to know the durability of the eutectic PCM, acceleration thermal melt/freeze cycles test in an in-house designed cycle tester was carried out for 1500 cycles. The stability of the eutectic was evaluated by thermal gravimetric analysis (TGA) analysis. These findings reveal that the variation in latent heat of fusion is not more than 15% and the chemical properties does not show any changes in the function group after 1500 cycles. The comparison result suggests that the prepared eutectic PCMs can be a probable candidate in medium-temperature range for solar-based energy storage applications.

Automated summary

This study outlines the development of eutectic phase change material (PCM) with different mass fraction ratios and determines its thermal properties. The eutectic mixture was prepared using polyethylene glycol (PEG) with atomic weights of 10,000 and 6,000. The phase transition temperature and fusion latent heat were evaluated using differential scanning calorimetry (DSC), while the chemical composition was analyzed using Fourier transform infrared spectroscopy (FT-IR). The results show that the sample with a mass fraction ratio of PEG 6,000 to PEG 10,000 of 60:40 has the highest latent heat of fusion at 194.52 J · g(-1). The durability of the eutectic PCM was evaluated through 1,500 cycles of thermal melt/freeze tests and thermal gravimetric analysis (TGA). The findings indicate that the variation in latent heat of fusion is less than 15% and the chemical properties remain unchanged after 1,500 cycles. The prepared eutectic PCMs show potential for use in medium-temperature solar-based energy storage applications.