十二水磷酸氢二钠复合相变材料的制备及其性能研究

Preparation and Performance of Composite Phase Change Materials with Disodium Hydrogen Phosphate Dodecahydrate

在十二水磷酸氢二钠(DHPD)中添加气相SiO2、九水硅酸钠(SMN)、和十水焦磷酸钠(TPD)作为成核剂,添加海藻酸钠(SA)和黄原胶(GX)作为增稠剂,通过步冷实验、加热-冷却循环及光学显微镜观察选出对该水合盐最优比例的成核剂和增稠剂;实验结果表明:在添加质量分数4.0%的SMN和1.0%的SA后,DHPD复合材料具有优异的相变焓(249.5 J/g),很低的过冷度(1.4℃),无相分离,相变温度为31.0℃,经过100次热循环后,复合材料仍然具有较高的焓值(239.4 J/g)。

Sodium silicate hydrate(SMN),gas-phase SiO2and sodium pyrophosphate decahydrate(TPD)were added to disodium hydrogen phosphate dodecahydrate(DHPD)as a nucleating agent,and sodium alginate(SA)and xanthan gum(GX)were added as thickening agents.The optimal ratio of nucleating agent and thickening agent for this hydrated salt was optimized by step-cooling experiments,melt-cooling cycle and optical microscopy observation.The experimental results showed that the DHPD composites had excellent enthalpy of phase transition(249.5J/g),very low supercooling(1.4℃),no phase separation,and a phase transition temperature of 31.0℃after the additions of 4.0%SMN and 1.0%SA,and the composites still possessed high enthalpy(239.4J/g)after 100thermal cycles.