在具有相同电荷的表面活性剂-纳米粒子系统中的协会:界面和批量效应
Manaswini Gowtham V1, Swaraj Deodhar1, Sumesh P Thampi1
1Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India.
Langmuir : the ACS journal of surfaces and colloids
|August 20, 2024
概括
表面活性剂分子以惊人的方式吸附到具有相似电荷的纳米粒子上,改变粒子和接口特性. 这种由静电相互作用驱动的现象会影响分散特征,但不会影响批量特征,例如临界微粒度.
科学领域:
- 合体和表面科学科学
- 材料化学 材料化学
- 物理化学 物理化学
背景情况:
- 在水溶液中具有相似电荷的表面活性剂和纳米颗粒之间的相互作用尚不清楚,文献发现相互矛盾.
- 研究这些相互作用对于涉及纳米粒子分散和界面现象的应用至关重要.
研究的目的:
- 在类似的纳米粒子和表面活性剂的二元混合物中从根本上研究散装和界面现象.
- 阐明静电相互作用在表面活性剂-粒子复合中的作用.
主要方法:
- 研究了带有阳性电荷的纳米粒子与阴离子表面活性剂和带有阴性电荷的纳米粒子与阴离子表面活性剂的二元混合物.
- 分析了批量和界面属性,包括粒子大小,泽塔潜力,表面张力和表面过剩度.
- 改变pH值以探索静电相互作用对表面活性剂-颗粒复杂化的影响.
主要成果:
- 表面活性剂分子在纳米粒子表面上吸附,尽管具有相似的电荷,导致粒子超电荷.
- 观察到分散物种特性 (大小,泽塔潜力) 和界面特性 (表面张力,表面过度度) 的显著变化.
- 在表面活性剂度较低时,效果更加明显,并且不依赖于纳米颗粒大小或表面活性剂-颗粒组合;关键菌度基本保持不变.
结论:
- 静电相互作用在表面活性剂-粒子复合中起着关键作用,驱动吸附和界面变化.
- 表面活性剂对类似充电的纳米颗粒的吸附是一种影响分散和界面行为的重要现象.
- 虽然批量性质,如关键的微粒度不受影响,但这些相互作用显著改变了界面和分散性质.
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