The effect of ultraviolet coating on containment and fire hazards of phase change materials impregnated wood structure

Abstract

Abstract Incorporation of phase change materials (PCM) in construction materials increases thermal mass of the buildings and reduces diurnal daily fluctuations of indoor air temperature. Direct impregnation is a cheap and easy method to embed PCM into the wood. The main shortcoming of this way is that the amount PCM is depleting over time that leads to degradation of the structure thermal mass and its capacity to store heat. In addition, the presence of PCM in construction materials increases the flammability of the structures. In this study, ultraviolet (UV) curable coating was used to improve containment of RT21 and propyl ester in wood and to reduce its flammability. Long exposure to storage temperature of 50 °C and room ambient temperature indicated that significant improvement was achieved in PCM retention in the wood through UV coating on the wood surface. Blending ammonium polyphosphate into the lacquer improved fire safety of the PCM impregnated wood as indicated by reduced ignition time and heat release rate from cone calorimeter test. Reduction in peak heat release rate by 20.5% and 37.4% was observed in RT21 and propyl ester respectively.