论文部分内容阅读
以膨胀石墨(EG)为载体材料,烷类(二十一烷、二十二烷)和脂肪酸类(正癸酸、硬脂酸)为相变材料,采用熔融共混法制备了不同类型膨胀石墨基复合相变材料,通过对其微观形貌、结构组成、热稳定性等表征测试,探究不同种类膨胀石墨基复合相变材料的热稳定性原理。结果表明,EG具有大量不同尺寸、结构和层次的微孔结构,是由10~50μm厚的石墨片叠合成的平行塌陷片层构成,具有良好的吸附性和稳定性,EG通过微孔束缚、氢键及表面极性等作用对相变材料进行物理吸附,使其热稳定性提高;随着EG含量的增加,烷类复合相变材料的热分解温度逐渐升高,分解速率减慢,脂肪酸类复合相变材料分解温度有所降低,分解速率减慢,但二者都在25~80℃间表现出良好的热循环稳定性,具有优良的热效率和热稳定性,满足中低温体系的温度调控要求。
Using expanded graphite (EG) as carrier material, alkanes (icosane, docosane) and fatty acids (n-decanoic acid and stearic acid) were used as phase change materials. Graphite-based composite phase change materials, through the microscopic morphology, structure, thermal stability and other characterization tests to explore the different types of expanded graphite-based composite phase change material thermal stability principle. The results show that EG has a large number of microporous structures with different sizes, structures and gradations. It consists of parallel collapsing sheets of 10-50μm thick graphite sheets with good adsorption and stability. EG is bound by micropores, Hydrogen bond and surface polarity of the phase change material for physical adsorption, to improve the thermal stability; with the increase of EG content, the thermal decomposition temperature of the alkyl composite phase change material gradually increased, the decomposition rate slowed down, the fatty acid The decomposition temperature and the decomposition rate of the composite phase change materials decrease, but both of them show good thermal cycle stability from 25 ℃ to 80 ℃, have excellent thermal efficiency and thermal stability, and meet the temperature of low and medium temperature system Regulatory requirements.