Preparation and thermal properties of polyethylene glycol/expanded graphite blends for energy storage

• Published in: Applied energy Vol. 86; no. 9; pp. 1479 - 1483
• Main Authors: Wang, Weilong, Yang, Xiaoxi, Fang, Yutang, Ding, Jing, Yan, Jinyue
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.09.2009; Elsevier
• Series: Applied Energy
• Subjects: acid blends; Applied sciences; composite; conductivity; energi- och miljöteknik; Energy; Energy- and Environmental Engineering; Energy. Thermal use of fuels; Exact sciences and technology; Expanded graphite; Form-stable materials; Heat transfer; phase-change material; Polyethylene glycol; Polyethylene glycol Expanded graphite Form-stable materials Thermal conductivity; Theoretical studies. Data and constants. Metering; Thermal; Thermal conductivity; Transport and storage of energy; Form-stable materials; Expanded graphite; Thermal conductivity; Polyethylene glycol; Latent heat; Ethylene glycol; Polyethylene; Temperature; Melting; Enthalpy; Thermal energy storage; Promoter; Thermal properties; Graphite; PCM material; Melting point; Glycol; Heat transfer; Energy storage
• ISSN: 0306-2619; 1872-9118; 1872-9118
• DOI: 10.1016/j.apenergy.2008.12.004

Expanded graphite is a promising heat transfer promoter due to its high conductivity, which improves the thermal conductivity of organic phase change materials. Moreover, it can also serve as supporting materials to keep the shape of the blends stable during the phase transition. After various investigation, the results showed that the maximum weight percentage of polyethylene glycol was as high as 90% in this paper without any leakage during the melting period, with the latent heat of 161.2 J g −1 and the melting point of 61.46 °C. It was found that the value of the latent heat was related to the polyethylene glycol portion, increased with the increase in polyethylene glycol content. Moreover, the measured enthalpy of the composite phase change materials was proportional to the mass ratio of the polyethylene glycol component. The melting temperatures were almost the same with different ratios of composites. The conductivity of blends was improved significantly with the high value of 1.324 W m −1 K −1 compared to the pure polyethylene glycol conductivity of 0.2985 W m −1 K −1.