Silicone rubber/paraffin@silicon dioxide form-stable phase change materials with thermal energy storage and enhanced mechanical property

A kind of silicone rubber (SR)/paraffin (Pa)@silicon dioxide (SiO2) composite form-stable phase change material (PCM) was developed in this paper. [email protected]2 was obtained by choosing Pa as PCM core microencapsulated in SiO2 shell based on tetraethoxysilane (TEOS) and γ-aminopropyl triethoxysilane (APTES) as precursors, then [email protected]2 microencapsules were embedded in SR matrix to fabricate SR/[email protected]2 composites. The SiO2 shell can provide a barrier for the melted Pa and meanwhile have reinforcing effect on SR as inorganic filler. The in-situ modification of SiO2 shell using APTES owing to the amino groups can not only prevent agglomeration, but also increase interfacial bonding between [email protected]2 with SR. The thermal and mechanical properties of the form-stable PCMs were characterized by differential scanning calorimetry (DSC) and mechanical tests. The results showed that the thermal and mechanical properties of SR/[email protected]2 composites were better than those of SR/Pa and SR/Pa/SiO2. Leakage test was conducted by heating the prepared composites over the melting temperature of Pa. The SR/[email protected]2 composites were found as form-stable PCM with low leakage rate. The phase change latent heat of the SR/[email protected]2 composites was up to 92.39 J g−1 and the composites can be used for thermal energy storage.