在超临界CO2中反向小细胞自组的分子动力学模拟
1Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599, USA.
Journal of the American Chemical Society
|August 19, 2004
概括
分子动力学模拟显示,在超临界的二氧化碳中,反向微粒的快速自我组装. perfluorinated 表面活性剂产生稳定的球形,与化不同,化不能形成微乳液.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 超临界二氧化碳 (scCO2) 是一种可调节的溶剂,应用越来越多.
- 反向微粒对于在各种系统中制造微乳液至关重要.
- 了解自组装动力学是设计功能性纳米材料的关键.
研究的目的:
- 通过分子动力学模拟,研究在scCO2中的反向微粒的自我组装.
- 为了比较 perfluorinated 和化表面活性剂在scCO2微乳液形成中的行为.
- 为了评估自组装的反向微粒的结构性质和稳定性.
主要方法:
- 分子动力学 (MD) 计算机模拟.
- 用完聚氨碳酸盐表面活性剂和水性核心对反向微粒的建模.
- 在5 ns的模拟时间内分析自组装动力学和总体形态学.
主要成果:
- 在大约5个小时内观察到逆细胞的快速自我组装,独立于初始条件.
- perfluorinated reverse micelles形成了稳定的球形聚合物,其特性与实验数据相匹配.
- 化表面活性剂类似物导致水和CO2之间的直接接触,表明微乳液形成不良.
结论:
- perfluorinated 表面活性剂在超临界的二氧化碳中有效地自我组装成稳定的球形反向微粒.
- 化表面活性剂不适合创建稳定的水/CO2微乳液.
- 模拟MD提供了宝贵的洞察力表面活性剂的行为和微乳液稳定性scCO2.
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