双胞胎半月形的微粒由选择性吸附合物形成
Shin-Hyun Kim1, Alireza Abbaspourrad, David A Weitz
1School of Engineering and Applied Sciences and Department of Physics, Harvard University, Cambridge, Massachusetts, USA.
Journal of the American Chemical Society
|March 23, 2011
概括
研究人员使用微流体创造了半月形的两粒子. 这些粒子通过形成一个保护层来稳定油在水中的乳液,防止滴滴凝聚.
科学领域:
- 材料科学 材料科学 材料科学
- 合体和表面化学
- 微流体学 微流体学
背景情况:
- 稳定乳液在各种行业中至关重要.
- 传统的乳液稳定剂可能有局限性.
- 开发新的两粒子提供了新的稳定策略.
研究的目的:
- 开发一种微流体方法,用于制造单分散的,半月形的两粒子.
- 研究这些颗粒在稳定油在水乳液中的使用.
- 了解这些新型微粒的稳定机制.
主要方法:
- 使用了theta (θ) 形毛细体微流体装置来控制油相注入.
- 采用可光固的单体和碳油混合与二氧化合物.
- 通过紫外线启动的聚合和选择性合物吸附诱导颗粒的形成.
- 在水-乙醇混合物中评估了乳液稳定性.
主要成果:
- 成功制备了单分散的,半月形的微粒.
- 证明二氧化合物选择性地吸附到油水界面.
- 证实了这些两粒子稳定油滴的能力.
- 在高表面密度下观察到颗粒的固定,防止滴滴聚合.
结论:
- 微流体提供了一种有效的途径来合成异性质的两性粒子.
- 半月形的颗粒提供了强大的稳定油在水乳液.
- 在足够的表面密度下,粒子固定是防止凝聚的关键.
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