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表面张力的透调节动力学:将兰迈尔动力学与高精度张力计相结合
1Department of Chemistry, Al al-Bayt University, Mafraq 25113, Jordan.
The journal of physical chemistry. B
|January 26, 2026
概括
一个新的动力热力学模型准确地预测了表面活性剂的动态表面张力. 该框架通过揭示界面平衡的一般规则,简化了用于喷雾剂和涂料等应用的表面活性剂设计.
科学领域:
- 物理化学 物理化学
- 表面科学是一门学科.
- 体和接口科学科学
背景情况:
- 动态表面张力测量对于理解界面现象至关重要.
- 现有的模型往往缺乏一般性,阻碍了对表面活性剂的预测设计规则的开发.
- 界面平衡动力学对于乳化,喷雾和涂料等过程至关重要.
研究的目的:
- 为动态表面张力开发一个最小的动力热力学框架.
- 通过将吸附-脱附动力学与热力学相结合,建立表面活性剂行为的一般设计规则.
- 通过各种表面活性剂类型,度和温度验证框架.
主要方法:
- 开发了一种框架,将两速吸附-脱吸,吉布斯吸附和阿雷尼乌斯温度依赖结合起来.
- 在离子 (SDS,CTAB) 和非离子 (Tween 80) 表面活性剂上使用力张力计验证了模型.
- 在温度范围 (10-80°C) 和表面活性剂度 (sub-到 supra-CMC) 进行实验,包括不确定性传播.
主要成果:
- 一个单独的闭式表达式准确地重现了动态表面张力 (R2 ≥0.99).
- 引入了一个Damköhler组 (Daγ) 来分割吸附-脱吸模式.
- 提取的趋势显示吸附率 (ka) 与散装度 (Cb) 增加到CMC,而脱吸率 (kd) 保持不变;观察到一致的激活能量和生成率.
结论:
- 开发的框架提供了一种通用方法来解释动态表面张力数据.
- 它可以将原始数据映射到基本的动力学和热力学参数.
- 这有助于合理选择表面活性剂的化学成分,度和温度,从而在工业应用中优化界面平衡.
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