Development of light rigid polyurethane foams containing thermoregulating microcapsules

Abstract

During the past years the incorporation of PCMs in building materials has been extensively studied.The combination of isolation and thermal storage properties that rigid polyurethane foams containing PCMs exhibit allows to reduce  the losses during the warming and cooling at the same time that they store energy, making these composites an ideal element for the increase of the energy efficiency of buildings. In order to combine both properties in an optimal way, in this work the development of rigid polyurethane foams (RPU) containing up to 30 wt% of thermorregulatory microcapsules at 700, 800 mbar and atmospheric pressure has been studied. The used thermorregulatory microcapsules have been obtained in a spray-drying pilot plant at the Instituto de Tecnología Química y Medioambiental (UCLM). Obatined foams have been physically (density), thermally (thermal energy storage capacity and thermal conductivity) and mechanically (modulus of elasticity in compression) characterized. As a result of this research, a RPU foam synthesized at 800 mbar, containing 30 wt% of microcapsules, with a latent heat of 21.3 J/g and a thermal energy storage capacity of 1.43 kWh/m3 has been obtained. In addition, this foam keep the isolation property of the polyurethane. The final composite presents a proper resistance to compression with a density that fulfills the Spanish regulation for the RPU foams application in buildings.