Shape-stable composite phase change materials encapsulated by bio-based balsa wood for thermal energy storage

Abstract

Abstract This paper shows a series bio-based shape-stable composite phase change materials (SSCPCMs) which were prepared through a convenient vacuum impregnation method by employing chemically treated wood (CTW) as the porous supporting material and myristic acid (MA), paraffin (PW) and polyethylene glycol (PEG) as the phase change working substance. After chemical treatment, the lignin and hemicellulose in the wood are removed, and the density of wood is further reduced, which allows it to absorb more phase change materials (PCMs). The weight percent ( ω ) of PCMs in the obtained MA/CTW-2, PW/CTW-2 and PEG/CTW-2 SSCPCMSs are 83.9%, 84.0% and 74.1%, respectively, and their latent heats are also as high as 179.1\xa0J/g, 181.9\xa0J/g and 132.6\xa0J/g, respectively. In addition, compared with PW/CTW-2 and PEG/CTW-2, the obtained MA/CTW-2 has better thermal management capability and excellent thermal reliability after 1000 heating-cooling cycles and 30 times of light-to-thermal conversion cycles experiment. Considering the processability and excellent properties, the obtained wood-based SSCPCMs have broad prospects in the practical application of thermal energy storage (TES).