三水醋酸钠复合相变材料的制备与性能

Preparation and performance of sodium acetate trihydrate composite phase change material

本文以2wt%十二水磷酸氢二钠(DSP)为成核剂、2 wt%羟乙基纤维素(HEC)为增稠剂、1wt%纳米二氧化硅为稳定剂,采用熔融共混法制备了含10 wt%额外水的三水醋酸钠复合相变材料。利用水热法并对材料的蓄热性能进行了测试。通过熔融—固化循环与步冷曲线,系统性地研究了三水醋酸钠相变复合材料在循环过程中的相变结晶稳定性。实验表明,复合材料的相变潜热高达232.91 k J/kg,材料在200次循环过程中过冷度始终保持在1.68~6.75℃,相变平台温度保持在56.07~57.94℃。同时,X射线衍射分析证实,循环实验结束后样品中未出现三水醋酸钠的相分离产物(无水醋酸钠),该材料的循环稳定性良好。

Sodium acetate trihydrate（SAT） composites containing 2 wt% disodium hydrogen phosphate dodecahydrate（DSP）, 2 wt% hydroxyethyl cellulose（HEC）, 1 wt% Nano-Si O2 and 10 wt% extra water were prepared by melt blending method and systematically tested for 200 thermal cycles by melting-solidification cycle and step cooling curve. Latent heat of phase change was determined by hydrothermal method. Results indicate that the material has higher latent heat of 232.91 k J/kg and better thermal cycling stability. Degree of supercooling and phase change temperature maintained 1.68~6.75℃ and 56.07~57.94℃ during 200 thermal cycles, respectively. It has been proved that no sodium acetate anhydrous generated by X-Ray Diffraction（XRD）.