Electricalthermal Properties And Heating Application Of CNT And CNT/Cu Papers

• Main Authors: Lin, Kean, 林格安
• Other Authors: Chen, Chienchong
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/33201175819357172691

碩士 === 國立中正大學 === 化學工程研究所 === 100 === In this thesis, CNT (carbon nanotube) and Cu/CNT papers were prepared by drop casting the CNT and CuNPs/CNT (nanoparticles) suspensions, respectively, onto the papers, where CuNPs were prepared by the low-temperature combustion method. When connected to battery at various voltages (9 to 24 volts), the as-prepared papers’ rose up by the resistance heating. The spatiotemporal temperature evolution was recorded by an infrared thermography camera. The steady-state temperature ranged from 38 to 90 ℃, rendering the as-prepared papers the plausible materials as the portable and flexible heating pad. Based on a heat transfer model, the recorded temperature data was used to fit the heat capacity as well as the heat transfer coefficient of the papers. Effects of various parameters on the temperature, resistance, and thermal properties of the as-prepared papers were exploited, including purification of CNT, adoption of surfactant in suspension preparation, removal of surfactant residue, different applied voltages, and wt % of CuNPs as well. Purification of starting CNTs by acid increased the temperature of papers by 15 %, because of the removal of the amorphous carbon. Temperature of papers with surfactant applied in suspension preparation was almost twice as much as the sample without it, due to the better dispersion of CNTs. In addition, washout of the surfactant residue by water in the papers could further increase the temperature by 26 %. It was found that the temperature of papers increased with the increasing applied voltage as well as the wt % of CuNPs, while electrical resistance of papers decreased with the increasing parameters. The heat transfer coefficient and heat capacity of Cu/CNT papers respectively ranged from 40.69 to 115.69 W/m2K and from 2.66 to 2.43 J/gK for the content of CuNPs increasing from 0 to 30 wt %. Removal of the surfactant residual in Cu/CNT papers could slightly raise both the heat transfer coefficient and heat capacity. In summary, the as-prepared CNT and Cu/CNT papers exhibited low electrical resistance, high heat transfer coefficient and heat capacity, and emitted temperature suited for human heating pad. The high heat transfer coefficient showed the ease of heat releasing. Although the heat capacity of the as-prepared papers was relatively large, the temperature was quickly raised to the steady-state temperature in less than 40 sec. The low electrical resistance indicated the low power consumption of the device, which was demonstrated by the 1-day effective working time.