Construction of Wheat Bran Biomass Porous Aerogel by Starch Pasting for Fabrication of Phase Change Composites with High Latent Heat Storage and Temperature Regulation

In order to improve the applicability in some extreme environments, a large number of research efforts have been conducted using carrier materials loaded with phase-change materials (PCMs). Wheat bran (WB), a kind of agroforestry waste and inexpensive biomass, is often ignored and discarded and further becomes a serious environmental threat. In this work, an effective high-value utility of WB in the field of composite PCMs was designed. First, briefness and efficient alkali-treated methods were adopted to control the degree of starch gelatinization of WB and the components within WB were entangled to form a three-dimensional network, and then the alkali–wheat bran aerogels (AWBs) were obtained via freeze-drying method. The AWBs were utilized as biomass carriers to incorporate polyethylene glycol (PEG), and the composite PCMs (AWBs-PEG) were fabricated. The morphological structure and the properties of antileakage, thermal storage, thermal stability, and temperature regulation of the fabricated composite PCMs were studied. The results indicated that AWBs exhibited excellent performances including good antileakage and high PEG adsorption rate (up to 86.2%). The melting and crystallization enthalpy values of AWBs-PEG could reach 153.5 J/g and 134.3 J/g, respectively. It could also be found that AWBs-PEG possessed a superior thermal cycle stability, thermal reliability, and temperature regulation ability. The integration of AWBs-PEG with temperature sensitive ink demonstrated an exciting color-change buffering property. It would provide an innovative direction for solar thermal energy storage, thermal infrared stealth, advanced smart textiles, and other research fields.