乙醇和相关的乙醇的热行为
Markus M Hoffmann1, Torsten Gutmann2, Gerd Buntkowsky2
1Department of Chemistry and Biochemistry, State University of New York Brockport, Brockport, New York 14420, United States.
Journal of chemical and engineering data
|January 15, 2025
概括
乙醇对凝固有动力障碍,形成固态相的难度各不相同. 这项研究量化了它们的热特性,提供了关于点和热容量的新数据.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
背景情况:
- 了解功能性酒精的热行为对于预测它们的相位过渡至关重要.
- 由于其分子结构,以太醇在固态形成中存在独特的挑战.
- 关于许多乙醇的热特性现有的数据是有限的.
研究的目的:
- 研究n-octanol和一系列相关的以太醇的热行为.
- 为了确定点,聚变热量和同体热容量.
- 描述这些化合物中固相形成的动力障碍.
主要方法:
- 差分扫描热量计 (DSC) 用于研究热过渡.
- 对一系列温度变化速率进行了测量.
- 数据分析的重点是识别暗示相变的内热和外热事件.
主要成果:
- 对n-Octanol的热性能 (点,聚变热,热容) 进行了与文献价值相比的验证.
- 乙醇显示出动力固化障碍,对冷却速度的反应不同.
- 六甲氧醇和四氧醇显示部分或条件固化,而二氧乙醇和五氧醇在加热过程中显示固体形成.
- 在测试条件下,3-布托西醇没有显示任何热事件,表明无形行为.
结论:
- 对于几个乙醇,获得了新的热数据 (点,热,液相热容量).
- 这项研究强调了分子结构和冷却速度对以太醇固化行为的显著影响.
- 在实验条件下,3-布托西醇似乎抵御结晶,这表明有无形固体形成的可能性.
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