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Updated: Jul 26, 2025
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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
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聚合物-表面活性剂复合物通过稀释和剪切的合体沉积
Lechuan Zhang1, Huda A Jerri2, Michael A Bevan1
1Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States.
Langmuir : the ACS journal of surfaces and colloids
|June 14, 2023
概括
这项研究揭示了如何通过调整聚合物表面活性剂混合物和剪切率来控制玻璃上的微粒沉积. 信息化设计允许为各种应用程序编程体沉积.
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
- 聚合物化学 聚合物化学
背景情况:
- 了解体颗粒沉积对于材料制造和表面修饰至关重要.
- 聚合物-表面活性剂相互作用显著影响着合体行为,影响着粘附和稳定性.
- 在各种工业过程中,在流量条件下控制颗粒沉积仍然是一个挑战.
研究的目的:
- 为了研究玻璃基板上的二氧化微粒沉积,脱落和重新沉积的动态.
- 阐明了性聚合物-阴离子表面活性剂组成和应用剪切速率对粒子行为的作用.
- 开发一种方法,通过受控的环境条件来编程合体沉积.
主要方法:
- 在流细胞中利用光学显微镜观察二氧化微粒的行为.
- 应用编程的剪切和稀释配置文件,以诱导和监测沉积,脱落和重新沉积.
- 测量了颗粒上的切割依赖扭矩,以量化聚合物表面活性剂复合体介导的粘合力.
主要成果:
- 在低剪速 (∼100 s−1) 的耗尽驱动沉积过程中,由于粘合力较弱,容易脱离.
- 由于强大的聚合物桥梁,颗粒抵御脱落,达到更高的剪切速率 (∼2000 s-1),可能来自表面活性剂的去除.
- 在聚合物-表面活性剂脱复杂化中观察到的途径依赖性,导致耐剪结构.
结论:
- 体沉积行为可以通过仔细设计初始聚合物-表面活性剂组合物和剪切配置文件来编程.
- 开发的粒子轨迹分析作为一种选工具,用于构成依赖的合体沉积.
- 结果为量身定制的表面功能和先进材料设计提供了洞察力.
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