Thermally conductive microcapsule/high-density polyethylene composite for energy saving and storage

Shih, Yeng-Fong Chen Pei Tian Lau Edwin M.; Hsu, Liang Rong

Phase change material (PCM) is useful for the storage and release of latent heat. However, its ability to conduct has hindered its engineering application. This study prepares a novel microencapsulated phase change material (MEPCM) by suspension polymerization. To improve the adhesion between the shell and the inorganic additive, triethoxyvinylsilane was incorporated copolymerizing with methyl methacrylate. Thermally conductive nanographite particle was added. This MEPCM was then incorporated into high-density polyethylene (HDPE) to form a series of thermally conductive PCM microcapsules that approached sphere shapes with diameters less than 2 μm. Thermal analysis showed that the thermal stability and heat resistance of the microcapsule were improved. The thermal conductivity of HDPE was increased by 39% to 0.6358 W/m ⋅K, and the surface resistivity was lowered to 2.78 × 105 Ω/sq after the addition of MEPCM. The temperature on the top of the composite tested was lower than pristine HDPE. This was close to the onset melting temperature of the MEPCM (38.5∘C), ∼5∘C lower than pure HDPE. The reduction is a significant improvement in temperature regulation. This enables MEPCMs to store and release heat much more effectively, and can thus be applied to medical construction materials to meet the temperature requirements of COVID-19 patients. [ABSTRACT FROM AUTHOR] Copyright of Modern Physics Letters B is the property of World Scientific Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)