Pn@MF@SiO2 Double‐Shelled Phase Change Microcapsules with High Latent Heat and Low Leakage Rate

Abstract

AbstractMicroencapsulation of paraffin with melamine formaldehyde shell (Pn@MF) shows the drawbacks of low thermal conductivity. Hence, we constructed SiO2 shells on Pn@MF phase change microcapsules by interfacial polycondensation to obtain Pn@MF@SiO2 double‐shelled microcapsules. The effect of tetraethoxysilane (TEOS) contents on the performance of Pn@MF@SiO2 was discussed in detail. As the TEOS contents increased, the thermal conductivity of Pn@MF@SiO2 gradually increased, reaching up to 0.376 W m−1 K−1. The Pn@MF@SiO2 have exhibited superior leakage‐proof properties and thermal reliability through double‐shelled protection, and the highest reduction in leakage rate reached 45.06 % compared to Pn@MF microcapsules. The Pn@MF@SiO2‐3 with the lowest enthalpy still exhibit a latent heat storage capacity of more than 176 J/g, which displayed outstanding latent heat storage/release capability and good anti‐permeable property.