Use of sustainable Phase Change Material (PCM) in mortars for building energy efficiency

Academic and industrial research are moving towards the development of innovative solutions and materials able to limit energy consumption for the thermoregulation of a building. One solution is the use of phase change materials (PCMs) that can absorb, store, and release energy according to their physical state that changes when the ambient temperatures changes. In this work, new sustainable PCMs were developed through the “form-stable” method according to the principles of Circular Economy. The new PCM materials consisted, in fact, of an inert matrix (obtained as byproduct of stone processing) impregnated by low toxic, low flammable polymer, namely polyethylene glycol (PEG). The PEG/stone composite materials were used to replace the fine aggregates in mortars based on different binders providing the mortars with thermoregulation performance. A comprehensive characterization was performed on the new PCMs by evaluating their thermal stability and thermal efficiency. The main properties (in fresh and hardened states) of the mortars with or without PCMs were analyzed. The mortars containing PCMs were also subjected to further investigations to evaluate their thermal behavior in response to external climatic conditions. Encouraging results were obtained, confirming the effectiveness of the mortars containing the new PCMs in the thermoregulation of indoor environments.