Mechanical and Thermal Properties of Phase Change Aerated Concrete with Paraffin Microcapsule

In this paper, phase change paraffin microcapsule and aerated concrete are combined to construct a new type phase change aerated concrete. Four groups of specimens with 0%, 2.5%, 5%, and 7.5% of microcapsule phase change material (MPCM) were manufactured. Comprehensive tests, including microstructure characterization, dry density, compressive strength, and thermal parameter tests were conducted to evaluate the influence of MPCM on mechanical and thermal properties of the phase change aerated concrete. Scanning electron microscope diagrams show that the structure of MPCM is complete in the cement substrate without damage. The test results show that with the increase of the content of MPCM: (1) density, peak strain, specific heat capacity, and heat storage coefficient increase; (2) elastic modulus and thermal conductivity decrease; and (3) the cubic compressive strength and the ultimate prismatic strength increase first and then decrease. Based on this study, the optimal content of MPCM is 2.5%, which performs better than non-autoclaved aerated concrete without MPCM in terms of both mechanical and thermal properties.