Preparation and Characterization of Composite Phase Change Materials Based on Lauric‐Myristic Acid and Expanded Vermiculite with Carbon Layer

Abstract

The low thermal conductivity and poor shape stability of phase change materials (PCMs) limit their application in the field of energy‐saving buildings. Lauric‐myristic acid (LA‐MA)/modified expanded vermiculite (MEV) composites as form‐stable phase change materials (FS‐PCMs) were prepared in this study. To improve their heat transfer properties, expanded vermiculite (EV) was impregnated with sucrose, starch and glucose solutions and then carbonized at a high temperature to attain MEVs, which act as a matrix in the PCMs. LA‐MA was adsorbed into the MEVs to obtain the LA‐MA/MEV FS‐PCMs. Scanning electron microscopy (SEM) shows that both EV and MEV have highly porous structures and can be used as PCMs carriers. The composite PCMs impregnated with starch obtain the best heat transfer properties in comparison with the other two samples. The melting temperature of the composite PCMs is 34.2 °C and the melting latent heat value is 141.9 J/g. Thermogravimetric analysis (TGA) shows that the composite PCMs present good thermal stability. Overall, LA‐MA/MEV FS‐PCMs are promising energy efficient materials that can be used as building materials.

Multienergy-Triggered Composite Phase-Change Materials Based on Graphite Foams Synthesized from Graphite Extracted from Spent Lithium-Ion Batteries

“…This is because the GF supporting material had no phase transition contribution. Furthermore, the phase transition enthalpies of the GF-PW CPCM samples during melting ranged from 174.2 to 209.2 J/g, which were higher than those of other CPCMs reported previously. ,− …”

“…Phase-change materials (PCMs) have been widely studied for solar-thermal applications owing to their advantages of maintaining a constant temperature during heat absorption and release and their high energy storage density and thermal efficiency. , Moreover, considering the disadvantages of solar energy utilization, such as intermittency, instability, and time–space mismatch, PCMs with electrothermal conversion abilities are promising solutions that have good application prospects for the thermal management of electronic equipment and as off-peak electricity conversion systems. − Therefore, the development of PCMs with dual photo/electrothermal conversion capabilities is an emerging development trend …”