Magnesium oxychloride cement with phase change material: Novel environmentally-friendly composites for heat storage

Abstract

To solve heat energy storage of building enclosure systems, phase change materials (PCMs) were implemented into magnesium oxychloride cement (MOC) to form a MOC-PCM composite. Such composites possess sufficient mechanical strength for specific usage and high heat storage efficiency. The chemical and physical properties of raw materials were investigated as well as fresh composite mixture rheology. On matured samples, structural, mechanical, hygric, and thermal properties were tested. The results suggest that the enrichment of MOC with PCM particles causes an increase in porosity, hence a decrease in the specific density of the composites. With each addition of PCM the reduction of mechanical properties of the composite material occurs, where the maximum reduction in flexural and compressive strength for the sample with 40 wt % of PCM is around 80%. The low strength of the composite is compensated by excellent thermal properties that are required for its intended application. The enthalpies of phase changes increased linearly with the dosage of PCM and can contribute to the passive moderation of temperature fluctuations. The developed composites can find use in building engineering in the form of indoor cladding panels, facing slabs ceiling boards, etc. Which can be beneficially applied for example in the passive cooling of attic rooms and retrofitting of the present building stock.

Keywords

• Magnesium oxychloride cement
• Phase change material
• Thermal performance
• Latent heat storage
• Mechanical and hygric parameters