Controlled synthesis and thermal management studies of SiO2@n-Octadecane phase change nanocapsules

Phase change capsules effectively address the limitations of leakage and poor stability of phase change materials (PCMs). In this study, SiO₂@n-Octadecane phase change nanocapsules (PCNCs) with controllable size and structure are prepared by controlling material ratios. When Water-to-EtOH ratio is 2:1 and C₁₈-to-TEOS ratio is 3:3 in the reaction system, prepared PCNCs show excellent phase change enthalpy of 152.9 J/g and high encapsulation ratio of 73.77 %, with desirable thermal stability and reliability. After the irradiation of simulating sunlight for 1500 s, the PCNCs achieved a temperature buffer of 6 °C compared with blank cotton fabric, and the cotton fabric with the PU coating containing the PCNCs presents up to 13.2 °C temperature reduction compared with original cotton fabric. The prepared SiO₂@n-Octadecane PCNCs present excellent heat storage and thermal management performance and effective strategy to develop long-term thermal comfort smart textiles.