几种相变材料熔化焓的研究

发布时间：2018-05-26 14:39

本文选题：相变材料 + 基团贡献法　；参考：《北京理工大学》2015年硕士论文

【摘要】：相变材料(phase change material,PCM)是指在一定的温度范围内可以改变物理状态的功能材料,在不同的相之间变化的过程中相变材料会吸收和释放大量的潜热,从而实现储热、放热功能,具有清洁环保、可实现能量的储存和重复利用的良好特性。本论文简述了相变材料国内外的研究进展和发展趋势、相变材料的分类以及在各领域的应用情况。重点研究了烷烃类(碳数13-36)、醇类(碳数13-18)、羧酸类(碳数10-20)、醚类(碳数24-36)有机相变材料的熔点和熔化焓变化规律。运用基团贡献法计算了烟酸、异烟酸、间氨基苯甲酸、对硝基甲苯、对羟基苯甲酸的熔化焓值,通过DSC实验测试了上述几种物质的熔点和熔化焓值,并且将计算值、实验测量值、文献中参考值进行了比较和误差分析。文章还单独研究了异烟酸的熔化焓值,DSC测试结果表明异烟酸熔点温度为288.9 oC,此时放出的热量为1040 J/g,该值与文献中提供的异烟酸熔化焓值135 KJ/mol(1097.5 J/g)存在误差5.24%。TG测试结果表明异烟酸277.4 oC时已经完全分解;而热裂解测试结果表明异烟酸在600 oC时并未裂解。因此,文献中提供的参考值只是异烟酸的升华焓值。文章最后调研了一部分中高温相变材料,例举了少数中温相变材料的熔点和熔化焓值。重点介绍了几类高温相变材料,并且列出了碳酸盐、氯化盐、硝酸盐、氟化盐等高温相变材料的熔点和熔化焓值。
[Abstract]:Phase change material (PCM) is a functional material that can change the physical state within a certain temperature range. In the process of changing the phase change between phases, the phase change material will absorb and release a large amount of latent heat, thus realizing the heat storage and exothermic functions. With clean and environmental protection, can achieve energy storage and reuse of good characteristics. In this paper, the research progress and development trend of phase change materials at home and abroad, the classification of phase change materials and their applications in various fields are briefly described. The changes of melting point and melting enthalpy of organic phase change materials of alkanes (carbon number 13-36), alcohols (carbon number 13-18), carboxylic acids (carbon number 10-20), ether (carbon number 24-36) were studied. The melting enthalpy values of nicotinic acid, isonicotinic acid, m-aminobenzoic acid, p-nitrotoluene and p-hydroxybenzoic acid were calculated by group contribution method. The melting point and melting enthalpy of the above mentioned substances were measured by DSC experiment, and the calculated values were calculated. The experimental measurements and the reference values in the literature are compared and the errors are analyzed. The melting enthalpy of isonicotinic acid was studied separately. The results showed that the melting point temperature of isonicotinic acid was 288.9 OC, and the heat released was 1040 J / g. There was an error 5.24%.TG test result between this value and the melting enthalpy value of isonicotinic acid provided in the literature (135 KJ/mol(1097.5 J / g). The results showed that isonicotinic acid was completely decomposed at 277.4 OC. The pyrolysis test showed that isonicotinic acid did not cleavage at 600oC. Therefore, the reference values provided in the literature are only the sublimation enthalpy of isonicotinic acid. At the end of this paper, the melting point and melting enthalpy of a few medium temperature phase change materials are discussed. Several kinds of high temperature phase change materials are introduced, and the melting point and melting enthalpy of carbonate, chloride, nitrate, fluoride and other high temperature phase change materials are listed.
【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB34

【引证文献】