对基西兰和基基离子液体的热力学研究
Rodrigo M A Silva1, Hadrián Montes-Campos1, Ana I M C Lobo Ferreira1
1CIQUP, Institute of Molecular Sciences (IMS), Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, Porto 4169-007, Portugal.
The journal of physical chemistry. B
|April 4, 2024
概括
在离子液 (IL) 中用取代碳可以降低粘度,同时保持广泛的液体范围和热稳定性. 含有的IL表现出可预测的热容量和挥发性的变化.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 离子液体 (ILs) 是具有可调节性质的多功能溶剂.
- 了解ILs的热力学行为对于其应用至关重要.
- 基和基链为ILs提供了新的结构修饰.
研究的目的:
- 为了研究带有基和基链的离子液体 (IL) 的热力学特性.
- 探索结合,锡洛链接和链条长度对IL特性的影响.
- 为了比较基于的ILs与基于碳的类似物的行为.
主要方法:
- 不同扫描热量计 (DSC) 和热重力计分析 (TGA) 测量热和相位行为.
- 高精度下降热量测量和差异扫描微热量测量用于热容量.
- 用石英晶体微平衡 (KEQCM) 测量挥发性和凝聚能量的Knudsen喷方法.
- 对气相能量和分子内相互作用的计算研究.
主要成果:
- 玻璃过渡温度与链条的灵活性相关.
- 摩尔热容量随着基链的长度线性增加.
- 在ILs中用取代碳,可使摩尔热容量增加约30 J·K−1·mol−1.1.
- 与碳类型相比,以为基础的IL显示出略有增加的挥发性,由于凝聚能降低,基IL具有更大的挥发性.
结论:
- 将纳入ILs有效降低粘度,同时保持广泛的液体范围和高热稳定性.
- 基于的IL提供了一个有前途的途径,用于为特定应用量身定制IL属性.
- 观察到的热容量和挥发率趋势为设计新型离子液体提供了宝贵的见解.
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