在O/W乳液中的凝结频率:与模型实验的比较
Tatiana Marques Pessanha1,2, Shailesh Varade1, Anniina Salonen1
1Laboratoire de Physique des Solides, CNRS UMR 8502, Université Paris Saclay, Orsay 91405, France.
Langmuir : the ACS journal of surfaces and colloids
|November 4, 2024
概括
我们研究了油-在-水乳液,发现它们的凝聚是一种两步,热激活的过程. 这一过程由表面压缩弹性模量控制,离子和非离子表面活性剂之间存在差异.
科学领域:
- 合体和表面科学科学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 在许多工业应用中,乳液稳定性至关重要.
- 了解滴滴凝聚是预测乳液寿命的关键.
- 表面活性剂的特性显著影响了乳液的行为.
研究的目的:
- 为了研究油在水乳液的凝聚力学.
- 为了确定控制相位分离速度的因素.
- 为了比较由离子和非离子表面活性剂稳定的乳液的凝聚行为.
主要方法:
- 使用基油和各种表面活性剂 (阴离子,非离子,聚合物) 制备油在水乳液.
- 在重力下观察相位分离,化和凝聚.
- 应用的Dinh等人. 模型将凝聚时间与激活能量联系起来.
- 测量表面张力和计算吉布斯吸附方程,以确定表面压缩弹性模量.
主要成果:
- 阶段分离发生在两个不同的步骤:最初的化,随后是快速凝聚,后来是戏剧性的凝聚.
- 完整相位分离时间 (Tc) 与凝聚频率和激活能量相关.
- 凝结是一种热激活的过程,由表面压缩弹性模量控制.
- 离子表面活性剂表现出两步膜破裂过程,与非离子表面活性剂不同.
结论:
- 稳定的油在水乳液的凝聚是一种热激活的过程.
- 表面压缩弹性模块是控制乳液凝聚的关键参数.
- 离子和非离子系统之间的凝聚行为差异归因于不同的膜破裂机制.
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