Na2CO3·10H2O-Na2HPO4·12H2O/SiO2复合定形相变材料的制备及应用
Preparation and application of Na2CO3·10H2O-Na2HPO4·12H2O/SiO2 composite shape-stabilized phase change materials
王璇 1李再超 1吴亚楠 1唐炳涛 1张宇昂1
作者信息
- 1. 大连理工大学 精细化工国家重点实验室,辽宁 大连 116024
- 折叠
摘要
以 Na2CO3·10H2O(SCD)、Na2HPO4·12H2O(DHPD)为相变主体制备了共晶体系,通过绘制凝固点变化图与DSC测试共同确定在m(SCD)∶m(DHPD)=4∶6 时形成共晶,FTIR和XRD结果显示,2 种水合盐间没有发生化学反应,但其晶型结构发生改变.通过添加质量分数为 2%的Na2SiO3·9H2O作为成核剂降低体系的过冷度,且经历 50 次相变循环体系未出现相分离,相变焓值仅下降 0.25%.进一步使用质量分数为 25%的气相SiO2 作为支撑材料,采用浸渍法制备了相变前后形状稳定的共晶水合盐/SiO2 定形相变材料(SSPCM).所得SSPCM的相变温度为24.08℃,相变焓值为146.6 J/g,过冷度为0.55℃,热导率为0.4571 W/(m·K).同保温泡沫相比,其可将模拟房内部中心温度的升温时间延长了1.81倍,降温时间延长了0.39倍.
Abstract
The eutectic system was prepared from Na2CO3·10H2O(SCD)and Na2HPO4·12H2O(DHPD)phase change materials,and it was found that the eutectic system was formed when m(SCD)∶m(DHPD)= 4∶6 by a solidification point variation diagram construction and DSC test.FTIR and XRD results revealed that the crystal structure was changed though there was no chemical reaction between the two hydrated salts.Na2SiO3·9H2O with a mass fraction of 2%was added as nucleating agent to reduce the undercooling of the system.Meanwhile,the system showed no phase separation and only a 0.25%decrement in enthalpy after undergoing 50 cycles of phase transition.Furthermore,a shape-stablized phase change material(SSPCM)consisting of eutectic hydrate/SiO2 with a mass fraction of 25%was prepared by impregnation.The obtained SSPCM exhibited a phase transition temperature of 24.08℃,an enthalpy of 146.6 J/g,an undercooling of 0.55℃,and a thermal conductivity of 0.4571 W/(m⋅K).Compared with conventional insulation foam,the SSPCM extended the heating time to raise the simulated indoor core temperature by 1.81 times and prolonged the cooling time by 0.39 times.
关键词
Na2CO3·10H2O/Na2HPO4·12H2O/共晶水合盐/复合相变材料/建筑节能/功能材料Key words
Na2CO3·10H2O/Na2HPO4·12H2O/eutectic hydrate salts/composite phase change materials/building energy conservation/functional materials引用本文复制引用
基金项目
国家重点研发计划项目(2022YFB3806500)
国家自然科学基金项目(22108026)
国家自然科学基金项目(22108050)
出版年
2024
NETL
NSTL
万方数据