Preparation of conductive filler / phase change material composites

• Main Authors: Yu-Wen Huang, 黃郁雯
• Other Authors: Yeng-Fong Shih
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/64938259287767308905

碩士 === 朝陽科技大學 === 應用化學系碩士班 === 101 === As a phase change material (PCM), paraffin or octadecanol has high latent heat, but low thermal conductivity. In this study, different proportion of boron nitride (BN), expanded graphite (EG) and multi-walled carbon nanotubes (MWCNT) were added into paraffin and octadecanol to form a high thermal conductivity composite material with high latent heat value, as well as a high electrical resistance. Moreover, the EG and MWCNT were organo-modified (C18-E and C18-C) to improve their compatibility with matrix (paraffin and octadecanol). The thermal conductivity, electrical resistance, morphology and thermal storage and heat release of the composite materials were investigated. Thermal conductivity of paraffin (0.308 W/m．K) was increased to 6.328 W/m．K, indicating the formation of conducting path and network, and the electrical resistance can reach to 3.83×106 Ω/□. The results of scanning electron microscope (SEM) reveal that good compatibility was observed between the matrix and the thermally conductive materials. Differential scanning thermal analysis (DSC) shows that the phase transition temperature of the composite material was similar to that of the matrix, and the phase change enthalpy of the composite was proportional to the content of the matrix in the composite. III Moreover, the thermal storage time of composite was shorter than the matrix by 47.7%; exothermic time was also significantly reduced by 77.9%. On the basis of all results, it revealed that the use of modified and mixed conductive additives can be considered an effective method to enhance the thermal conductivity, and thermal storage and exothermic rates of PCM, as well as a high electrical resistance.