Improving the phase change properties of paraffin wax by regulating the pore structure and surface properties of silica aerogel

Abstract

This study highlights the significance of the difference between the melting and solidification temperatures of phase change materials (PCMs) in their practical applications. We incorporated the wood fiber as a support phase and used alkylation to modify the pore structure and surface properties of silica aerogels. The effect of different pore size distributions and surface properties on the phase change properties of PCMs was investigated. The results showed that nanopores increased pressure and the melting point of PCMs while the weak interaction force on the substrate surface decreased their solidification temperature. Furthermore, using matrices with unique properties, such as mesopore and hydrophobic aerogels, proved to be effective in reducing the difference between the melting and solidification temperatures by up to 44.1 % compared to pure paraffin wax. Moreover, hydrophobic groups enhanced the encapsulation performance of the composite, effectively isolating the influence of water.