Development of polyurethane foam incorporating phase change material for thermal energy storage

The major aim of the present study is to improve the thermal characteristics of polyurethane foams (PUFs) that have been almost exclusively used for thermal insulation purposes but can also play a role in potential thermal energy storage components as a matrix material. To overcome the low thermal conductivity of the of PUFs matrix, a synthesized phase change material (PCM) based on paraffin and calcium carbonate (CaCO3) has been developed to enhance the thermal conductivity and thus achieve a more effective charging and discharging process. The synthesized PCM (PCM@CaCO3) exhibited a good phase change performance with significant thermal storage capacity and thermal stability compared to commercial based PCM (PCM@BASF). Different PUFs formulations incorporating PCM (PCM@CaCO3 and PCM@BASF) were used to produce PUFs panels (rigid and soft PUFs panels). The thermal conductivity of the PUFs panels was measured using the transient plane heat source method (HotDisk Analyser, TPS 2500 S) and the thermal flux metre method (steady-state method). The results obtained revealed that, regardless of the method used, the thermal conductivity profile has a similar increasing trend before and after the bounds of the PCM phase change transition zone, whilst during PCM phase transition both methods showed a decreasing trend of the thermal conductivity as the temperature increased. In addition, this work presents and discusses the limitation of the HotDisk method to analyse panels composed by multilayers.