SR/GNPs/Pn@SiO₂ shape-stabilized phase change composites with low leakage rate and adjustable thermal energy storage

Abstract

The storage of latent heat using phase change materials (PCM) is an effective method of energy storage. In this study, silicone rubber (SR)/graphene nanoplates (GNPs)/paraffin@SiO₂ phase change microcapsules (Pn@SiO₂) shape-stabilized phase change materials (SSPCM) with high thermal conductivity, low leakage rate and tunable thermal management capability are prepared by method of add phase change microcapsules and thermal conductivity enhancer graphene nanoplates. The effects of Pn@SiO₂ content on properties of the SR/GNPs/Pn@SiO₂ (SGP) composites were investigated by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry. The results show that the enthalpy of phase change composites can be adjusted from 25.6 to 78.56 J·g⁻¹ by changing the addition amount of Pn@SiO₂ microcapsules. Moreover, the effect of GNPs on the thermal conductivity of SR matrix is greater than that of Pn@SiO₂ on SR, as a consequence, the thermal conductivity of SGP composites decreases with the increase of Pn@SiO₂. In addition, the thermal conductivity of SGP phase change composites can also reach 0.567 W·m⁻¹K⁻¹ after the addition of microcapsules, which dramatically shortens the response time of the material in the application. In summary, SGP composites have promising applications in the field of thermal storage.

Keywords:

• Shape-stabilized phase change composites
• phase change microcapsules
• low leakage rate
• silicone rubber
• thermal conductivity

Acknowledgements

This work was financially supported by NSAF of China [No. U1730114]; Open Foundation of NHC Key Laboratory of Nuclear Technology Medical Transformation (MIANYANG CENTRAL HOSPITAL) [No.2021HYX020]; Project of State Key Laboratory of Environmental-friendly Energy Materials [No.21kfhg15 and No.21fksy26].