Preparation and characterization of oligomeric thermal phase change polyurethane foam

The generation of a large amount of heat during the formation process of polyurethane foam (PU) hinders the large-scale applications of the materials. Phase-change materials (PCM) can be introduced into PU to reduce the amount of heat accumulation inside PU. Silica-based urea-formaldehyde heteroshell phase-change microcapsules (S-MPCM) containing polydopamine were fabricated, followed by the fabrication of a novel composite polyurethane foam (PU/S-MPCM) doped with S-MPCM. The latter was fabricated using 4,4′-diphenylmethane diisocyanate and polyether polyol as the primary raw materials. The results revealed that the modifying effect of polydopamine resulted in the SiO2 layer deposited on the surface of the microcapsules improved the densification of S-MPCM, and the encapsulation rate of S-MPCM was 76.5 %, and the enthalpy of melting was 162.4 J/g. The compatibility of S-MPCM with the foam was also further improved, increasing the toughness of the composite foam and maximizing its retention of morphology after compression testing. The maximum internal temperature of the composite foam blended with 10 % S-MPCMs was reduced to 53.7 °C, showing excellent thermal regulation performance. The oligomeric thermal phase change polyurethane foam prepared in this study can be considered for applications such as building insulation and mine grouting.