非离子和离子表面活性剂之间对化过程和液体/空气表面吸附的协同效应
Kristo Kotsi1, Teng Dong1, Takeshi Kobayashi2
1ThAMeS Multiphase, Department of Chemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK. p.angeli@ucl.ac.uk.
Soft matter
|December 20, 2023
概括
预测表面活性剂混合物的行为是具有挑战性的. 这项研究揭示了混合微粒和接口中的吸引力,而三甲基乙酸盐 (EOT) 丰富了这些结构,影响了微粒临界度 (CMC) 值.
科学领域:
- 合体和表面科学科学
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 预测混合表面活性剂溶液的行为,特别是那些具有不同临界菌根度 (CMC) 的溶液,是复杂的.
- 了解界面和微粒中的分子相互作用对于设计农业化学品等产品中有效的表面活性剂系统至关重要.
研究的目的:
- 为了研究混合非离子 (三乙乙酸盐,EOT) 和离子 (二硫酸盐,NaDDBS) 表面活性剂的平衡和动态表面张力.
- 根据各种摩尔比率和制备方法 (预混合与逐一添加) 确定这些混合物的CMC值.
主要方法:
- 研究了EOT/NaDDBS混合物的平衡和动态表面张力,其摩尔比为0.01,0.1,1和4.
- 分析了两种制备方法:预混合并逐一添加.
- 应用常规溶液理论来分析混合微粒内部和接口上的相互作用.
主要成果:
- 与单个表面活性剂相比,混合物表现出明显更长的平衡时间,特别是预混合系统 (长达15小时).
- 低EOT/NaDDBS比率的CMC值 (0.01,0.1) 在单个表面活性剂的CMC值之间.
- 较高的EOT/NaDDBS比率 (1, 4) 导致CMC低于任何单一表面活性剂.
- 正则溶液理论表明,在接口和混合微粒中存在着吸引力,具有EOT的优先丰富.
结论:
- 制备方法和摩尔比率极大地影响混合表面活性剂系统的表面张力行为和CMC.
- 具有吸引力的相互作用和优选的EOT丰富性决定了这些混合表面活性剂在散装和接口上的自我组装.
- 结果为设计先进的表面活性剂配方提供了见解,用于诸如农业化学输送系统等应用.
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