Preparation, characterization and thermal regulation performance of cement based-composite phase change material

Thermal behavior of a building mass can be enhanced using phase change materials (PCMs) as latent heat thermal energy storage (LHTES) materials. Such type thermal enhanced construction materials can be used for passive solar heating, ventilating and air conditioning (HVAC) purposes in building envelopes. This work was focused on development, characterization of LHTES properties and establishment of thermal performance of a cement-based composite PCM (Cb-CPCM) plaster for low-temperature LHTES targets in buildings. The eutectic mixture of capric acid(CA)-myristic acid(MA) was absorbed as 28 wt% by cement through vacuum embedding method. The chemical structures and morphology cement/(CA-MA) composite and its pure components were investigated by FT-IR, XRD and SEM techniques. The LHTES characteristics of the produced Cb-CPCM were determined by DSC analysis. The DSC results indicated that the form-stable Cb-CPCM melted and solidified at 21.13 and 17.90 °C and had corresponding LHTES capacities as 41.78 and 39.56 J/g, respectively. The TGA results and cycling test revealed that the Cb-CPCM had high thermal resistance, long-term cycling chemical stability and reliability. Furthermore, two cubic test rooms were built with/without Cb-CPCM to compare thermo-regulating performance in laboratory-scale. The temperature difference between the indoor temperatures of the cubes was measured as averagely 0.78 °C during heating period. All results exhibited that the prepared Cb-CPCM could be considered as a potential composite PCM for low-temperature HVAC intentions in buildings.