A composite of cross-linked polyurethane as solid–solid phase change material and plaster for building application

International audienceThis paper presents the thermal and mechanical characterizations of a composite material made of plaster and home-made solid–solid Phase Change Material (s-s PCM) to be considered as a building material in order to: increase thermal inertia of buildings, improve comfort of the inhabitants, and reduce the primary energy needs of buildings.The use of those s-s PCM allows to avoid the problems of liquid–solid PCM that were considered into building materials. The s-s PCM involves a transition from polymeric amorphous to crystalline phase. They remain in a solid state under 100 °C and are water resistant. Physical properties of the s-s PCM are such that the grain size can be controlled for incorporation and mixing with plaster before water addition.The thermal properties of the composite were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Further composite is instrumented with K type thermocouple during exposition to thermal cycling around ambient temperature in a stove with fixed humidity. The microstructure of the PCM-bearing composite was observed by scanning electron microscopy (SEM). The incorporation of the PCM into the plaster matrix does not change the thermal properties of PCM. The thermal monitoring of the composite shows a modification of the maximum and the minimum peaks of temperature as well as a time offset of temperature variations. Some mechanical properties of the composite, such as compressive strength were investigated. Those preliminary results suggest that our s-s PCM can be considered further for incorporation into plasterboard that will passively contribute to a better thermal comfort in building application