Preparation of multifunctional phase change microcapsules for thermal energy storage and shielding against ionizing radiation

摘要

A novel type of multifunctional microencapsulated phase change materials (MPCMs) with BaCO_3 as shell and binary phase change materials (PCMs) as core was prepared based on self-assembly method. In addition to their original thermal storage properties, MPCMs are endowed with the ability to shield against ionizing radiation by the BaCO_3 shell containing high atomic number element Ba~(2+). Thermal analysis indicated that due to the composition of binary PCMs, MPCMs had phase transition points of 5.54 ℃ and 32.6 ℃, which enabled MPCMs with thermal storage function in wide temperature ranges. Furthermore, the cement paste containing different replacement ratio of MPCMs was exposed to X-ray radiation. The results showed that with the addition of MPCMs, the linear attenuation coefficient of cement paste had a general increase over the photon energy range of 0.05-0.15 MeV, especially at the lower photon energy. The multifunctional MPCMs developed in this study provides applicability for traditional thermal storage materials in building and other fields.