从光敏纳米乳液中证明的纳米级电荷调节
Dana Glikman1,2, Leonard Wyszynski1, Valentin Lindfeld3,4
1Institute of Physical Chemistry, University of Münster, Corrensstraße 28/30, 48149 Münster, Germany.
Journal of the American Chemical Society
|March 14, 2024
概括
研究人员使用光敏表面活性剂调整了油/水接口. 这控制了乳液稳定性和相隔,为纳米粒子稳定和可持续的表面活性剂使用提供了洞察力.
科学领域:
- 体和表面科学
- 材料科学
- 物理化学
背景情况:
- 乳液在日常生活中至关重要,需要控制它们的特性.
- 在分子层面了解油/水界面至关重要,但在实验上具有挑战性.
- 目前的方法很难在现场探测乳液接口.
研究的目的:
- 调查光敏表面活性剂的使用以调整乳液接口.
- 探索表面活性剂光异构对宏和纳米的作用.
- 了解宏和纳米乳液之间界面行为的基本差异.
主要方法:
- 在可见光和紫外线照射时经过E/Z光异构的使用光敏表面活性剂 (丁-AAP).
- 采用了诸如接口张力测量,临界细胞度测定,二次散和脉冲场梯度核磁共振 (NMR) 等技术.
- 研究了宏和纳米乳液滴粒大小, ζ-潜力,表面过量和界面性能的变化.
主要成果:
- 丁烯-AAP表面活性剂的光异构化大大改变了膜中的界面张力和关键菌根度,从而控制了稳定性和相分离.
- 纳米乳液 (R_H ~90 nm) 没有显示出因光异构化而导致的液滴大小或 ζ-潜在的显著变化.
- 在纳米面界面的表面活性剂过剩的可逆变化被观察到在纳米乳液中,与宏观乳液的行为不同.
- 证据表明固定的电荷与粒子大小比率和对电离子凝结对于纳米乳液稳定至关重要.
结论:
- 对光敏感的表面活性剂为控制乳液特性提供了一种新的方法.
- 由于尺寸依赖的静电稳定,纳米乳液与宏乳液相比表现出独特的界面行为.
- 由于度要求较低,研究结果支持在纳米粒子稳定中使用更可持续的表面活性剂.
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