Fabrication, property characterization and thermal performance of composite phase change material plates based on tetradecanol-myristic acid binary eutectic mixture/expanded perlite and expanded vermiculite for building application

Abstract

A binary eutectic mixture composed of tetradecanol (TD) and myristic acid (MA) was maximally absorbed into the microstructures of expanded perlite (EP) and expanded vermiculite (EVMT), respectively, through a self-made vacuum adsorption roller to prepare phase change material (PCM) particle (PCP). Then EP and EVMT-based composite PCM plates were respectively fabricated through a mold pressing method. The thermal property, chemical stability, microstructure and durability were characterized by differential scanning calorimeter (DSC), Fourier transform infrared spectroscope (FT-IR), scanning electron microscope (SEM) and thermal cycling tests, respectively. The results show that both PCPs have high latent heats with 110 J/g for EP-based PCP and more than 130 J/g for EVMT-based PCP, compact microstructure without PCM leakage, stable chemical property and good durability. The research results have proved the feasibility for the vacuum adsorption roller used in the composite PCM fabrication. Results of thermal storage performance experiment indicate that the fabricated PCM plates have better thermal inertia than common building materials, and the thermal storage performance of PCM plates has nonlinearly changed with outside air velocity and temperature increase. Therefore, PCM plates show a significant potential for the practical application of building thermal storage.

摘要

以十四醇−十四酸二元低共融混合物作为相变材料, 通过自制的真空吸附滚筒分别将其最大程 度地吸附到膨胀珍珠岩和膨胀蛭石的微观结构之中制备出相变颗粒, 然后使用压模法将相变颗粒分别 制备成膨胀珍珠岩和膨胀蛭石复合相变板。通过差示扫描量热仪(DSC)、傅里叶变换红外光谱(FT-IR)、 扫描电子显微镜(SEM)和热循环测试分别表征了相变颗粒的热性能, 化学稳定性, 微观结构和耐久性。 结果表明, 两种相变颗粒均具有较高的潜热, 膨胀珍珠岩相变颗粒能达到110 J/g, 膨胀蛭石相变颗粒 能达到130 J/g; 微观结构致密, 没有相变材料泄漏; 化学性质稳定, 耐久性好。研究结果证明了真空 吸附滚筒在复合相变材料制造中的可行性。蓄放热性能实验结果表明, 相变板比常见建筑材料具有更 好的热惯性, 相变板的储热性能随外界风速和温度的升高而呈现非线性变化。因此, 在建筑蓄热领域 中的应用相变板具有巨大潜力。