在冰和水中的多电解质溶液的相图
George Mallinos1, Ali Dhinojwala1
1School of Polymer Science and Engineering, The University of Akron, Akron, Ohio 44325, United States.
The journal of physical chemistry. B
|April 7, 2025
概括
多电解质 (PE) 与水有强烈的相互作用,影响冷保存和涂层. 这项研究揭示了相位图,显示了一个稳定的未水-PE相向下至-100°C,这对于控制冰的应用至关重要.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
背景情况:
- 多电解质 (PE) 与水具有强烈的相互作用,对于冷保存,抗结冰和滑等应用至关重要.
- 了解PE-水系统的相位图,特别是在低温下,对于优化这些技术至关重要.
研究的目的:
- 为了研究负电荷和正电荷的多电解质 (PE) 与低温水的相图.
- 将实验结果与理论模型进行比较,并阐明在缩PE-水阶段中的 counterions 的行为.
主要方法:
- 使用红外光谱 (IR) 和差分扫描热量计 (DSC) 来研究PE-水相行为.
- 分析了相位图,以确定冰和PE丰富的相位之间的共存曲线.
- 使用理论模型,包括Gibbs-Thomson和Flory-Huggins,进行数据比较.
主要成果:
- 确定了与富含PE相平衡的冰的共存曲线.
- 观察到相似的相位图,无论是正电荷还是负电荷的PE,大约40%是未结冰的水.
- 发现缩PE-水阶段的 counterions 密切相关,具有最小的热贡献,与预期相反.
结论:
- 这项研究揭示了一个稳定的,未结的水-PE阶段,持续到-100°C.
- 在缩PE-水阶段的对比协会偏离了预期的强解离.
- 这些发现对于开发各种技术应用中控制冰形成的先进材料具有重要意义.
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