Preparation and thermal properties of modified binary paraffin - Hexadecylamine shaped composite phase-change energy storage materials

Abstract

Binary paraffin has attracted much attention because it can control the phase change temperature range and has good flexibility. To improve the latent heat effect, a modified binary paraffin—hexadecylamine—ceramsite shaped composite phase-change energy storage material was prepared in this study through eutectic mixing and vacuum adsorption method. With eutectic binary paraffin—hexadecylamine as the core material, ceramsite as the carrier shell material and nano aluminum nitride (AlN) as the heat conduction enhancer. The thermal stability of the composites was characterized using a temperature recorder, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results showed that the optimal mass ratio of the eutectic phase-change material was solid paraffin: liquid paraffin: hexadecylamine = 50: 18: 32. The optimal mixture has a phase-change temperature of 26.5°C and a latent thermal value of 204.50 J/g, indicating that it has good heat storage performance. The phase-change temperature was 1.2°C earlier after the addition of 0.5% AlN, and the heat rate of storage was also improved. The mass ratio of the composite phase-change materials and ceramsite was 27.5: 72.5 is achieved by vacuum adsorption into the ceramsite. The phase-change materials are evenly dispersed and the ceramsite is well wrapped. It has good thermal stability, as verified by a 500 accelerated heating-cooling circulations below 60°C, and has great potential for the development of new building energy storage materials.