水基聚氨分散:使用软硬粒子模型对粒子电荷的详细分析
C Grau1, A M Schmidt2, J Wilkens1
1Faculty of Applied Natural Sciences, TH Köln─University of Applied Science, Leverkusen D-51379, Germany.
Langmuir : the ACS journal of surfaces and colloids
|October 9, 2024
概括
硬粒子模型准确地描述了水基聚氨分散 (PUD) 的电泳流动性,并考虑了粒子电荷和静电潜力. 这种模型比软粒子理论更好地了解PUD的行为.
科学领域:
- 合体和表面科学科学
- 聚合物化学 聚合物化学
- 电化学 电化学 电化学
背景情况:
- 基于水的聚氨分散 (PUD) 呈现出复杂的电泳性移动性,取决于电解质度.
- 了解粒子电荷和静电潜力对于PUD的表征至关重要.
研究的目的:
- 使用硬和软颗粒模型研究PUD的电泳运动性.
- 为了确定不同稳定剂和聚醇含量的PUD中的粒子电荷和静电潜力.
主要方法:
- 通过乙工艺合成PUDs.
- 用于粒子电荷表征的电位计酸定位.
- 用软粒子和硬粒子理论分析的电泳运动测量.
主要成果:
- 酸定位揭示了位于聚合物颗粒表面和内部的离子组.
- 软粒子模型是不合适的;硬粒子模型在包括放松效应时准确地描述了电泳运动.
- 泽塔潜能被硬粒子模型很好地模拟,表面潜力和剪切平面距离是恒定的.
结论:
- 硬粒子模型与软粒子模型相比,可以更好地描述PUD的电动行为.
- 尽管计算的表面电荷密度存在差异,但硬粒子模型对PUD电荷分布和行为提供了宝贵的见解.
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