改变形状和逆转两性Janus颗粒具有响应pH的表面活性物质特性
1Department of Chemical and Biomolecular Engineering, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|May 6, 2014
概括
研究人员开发了pH响应的Janus粒子,即双相合物,作为调节的固体表面活性剂. 这些颗粒可以稳定乳液,并通过改变它们的特性来响应pH值水平来控制它们的相位行为.
科学领域:
- 合体和表面科学科学
- 材料化学 材料化学
- 聚合物科学 聚合物科学
背景情况:
- 雅努斯粒子是具有明显表面化学成分的两性合体.
- 它们的两性使多相流体混合物如乳液等能够稳定.
- 响应刺激的分子双胞胎可以改变表面活性剂的特性,影响乳液形态和相位逆转.
研究的目的:
- 为了合成均的pH响应的Janus粒子.
- 研究它们作为动态调节的固体表面活性剂的能力.
- 为了证明它们在稳定和控制乳液特性中的应用.
主要方法:
- 使用聚合诱导相分离和种子乳液聚合合成.
- 创建了具有疏水性 (styrene) 和pH敏感的水友性 (酸) 侧面的Janus粒子.
- 研究了粒子聚合,形状和表面活性剂特性中的pH诱导的变化.
主要成果:
- 成功合成了高度均的pH响应的Janus粒子.
- 在pH值变化时,表面活性剂性质的完全逆转.
- 展示了油在水和油在水两种乳液的稳定性.
- 实现了pH诱导的乳液相位逆转.
- 通过改变pH,调整了乳液滴 (吸引力/排斥力) 之间的相互作用.
结论:
- 开发了一种新型的pH响应的Janus粒子.
- 这些粒子作为动态调节的固体表面活性剂起作用.
- 贾努斯粒子为乳液稳定和相位行为提供了先进的控制.
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