In order to solve the problems of high supercooling, poor thermal conductivity and phase separation after repeated use of Na₂S₂O₃·5H₂O with additives. In this paper, Na₂S₂O₃·5H₂O is used as the matrix phase change material, and 1% sodium carboxymethyl cellulose, 3% SrCl₂·6H₂O, and 10% expanded graphite (EG) are added to prepare the modified Na₂S₂O₃·5H₂O composite phase change energy storage material. Based on the existing research, the effects of reducing supercooling, improving thermal conductivity, and improving stability are further optimized. The phase change temperature, supercooling degree, heat release time, phase change latent heat, and thermal conductivity of the material are tested by temperature data acquisition instrument, differential scanning calorimeter, hot disk thermal constant analyzer, and other instruments. The effect of EG on the thermal conductivity of the Na₂S₂O₃·5H₂O composite phase change energy storage material was explored from the microstructure through a digital scanning electron microscope; Fourier transform infrared spectroscopy verified the composition of the composite phase change materials. After 200 cycles of melting and solidification, the improved composite phase change material has a phase change temperature of 43.49°C, a supercooling degree of 2.19°C, a phase change latent heat of 198.7 J/g, and a thermal conductivity of 3.42 W/m·K. Composite phase change material shows good thermal stability and provides strong support for phase change energy storage technology.

中文翻译：

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五水硫代硫酸钠/膨胀石墨相变储能复合材料的制备与表征

为了解决过高的过冷度，导热性差和重复使用Na ₂ S ₂ O ₃ ·5H ₂ O和添加剂的相分离问题。本文使用Na ₂ S ₂ O ₃ ·5H ₂ O作为基质相变材料，并向其中添加1％羧甲基纤维素钠，3％SrCl ₂ ·6H ₂ O和10％膨胀石墨（EG）。准备改性的Na ₂ S ₂ O ₃ ·5H ₂O复合相变储能材料。在现有研究的基础上，进一步优化了降低过冷度，提高热导率和提高稳定性的效果。材料的相变温度，过冷度，放热时间，相变潜热和导热系数通过温度数据采集仪，差示扫描量热仪，热盘热常数分析仪和其他仪器进行测试。EG对Na ₂ S ₂ O ₃ ·5H ₂导热系数的影响通过数字扫描电子显微镜从微观结构上探索了O复合相变储能材料。傅里叶变换红外光谱证实了复合相变材料的成分。经过200次熔化和固化循环后，改进的复合相变材料的相变温度为43.49°C，过冷度为2.19°C，相变潜热为198.7 J / g，导热系数为3.42 W / m·K。复合相变材料显示出良好的热稳定性，并为相变储能技术提供了有力的支持。