The establishment of Boron nitride@sodium alginate foam/polyethyleneglycol composite phase change materials with high thermal conductivity, shape stability, and reusability

Adopting organic phase change materials (PCMs) for the management of electronic devices is restricted by low thermal conductivity. In this paper, the composite PCMs are established by freeze-drying and vacuum impregnation. Herein, polyethylene glycol (PEG) is induced as heat storage materials, boron nitride (BN) is embedded as filler stacking in an orderly fashion on the foam walls to improve thermal conductivity and sodium alginate (SA) is formed as supporting material to keep the shape of the composite stable. X-ray diffractometry, scanning electron microscopy-energy dispersive spectrometer, thermal gravimetric analysis, thermal conductivity meter, differential scanning calorimeter, and Fourier transform infrared were used to characterize the samples and thermal cycles were employed to measure the shape stability. The results exhibit the BN@SA/PEG composite PCMs have good chemical compatibility, stable morphology, and thermal stability. Due to the high porosity of foam, PEG endows the composite PCMs with high latent heat (149.11 and 141.59 J·g−1). Simultaneously, BN@SA/PEG shows an excellent heat performance with high thermal conductivity (0.99 W·m−1·K−1), reusability, and shape stability, contributing the composite PCMs to application in the energy storage field. This study provides a strategy to manufacture flexible, long-serving, and shape-stable PCMs via introducing BN@SA foam as a storage framework, and these PCMs have great potential in thermal management in the electronic field.