聚合物和表面活性剂的水性多相系统提供了自组装的密度梯度梯度
Charles R Mace1, Ozge Akbulut, Ashok A Kumar
1Department of Chemistry & Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|May 19, 2012
概括
研究人员使用聚合物和表面活性剂创建了300多个稳定的水性多相系统 (MuPS). 这些系统可以根据密度准确地分离混合材料.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 分离科学 分离科学
背景情况:
- 水性多相系统 (MuPS) 是由水中的聚合物和表面活性剂混合物形成的.
- 这些系统表现出自我组装和热力学稳定性.
- 控制密度梯度对于分离应用至关重要.
研究的目的:
- 展示大量多种多相水系统 (MuPS) 的生成.
- 为了研究这些MuPS中密度梯度的特性.
- 展示MuPSs对于基于密度的对象分离的实用性.
主要方法:
- 从水性聚合物和表面活性剂溶液中产生超过300个MuPS.
- 阶段之间的密度梯度梯度 (Δρ ≈ 0.001 g/cm3) 的表征.
- 使用不同密度的玻璃珠和尼龙颗粒进行分离的演示.
主要成果:
- 成功生成了300多个MuPS,具有2-6个阶段.
- 实现了热力学稳定,时间不变的密度梯度,可通过共溶剂调节.
- 根据密度差异证明了对象的有效分离.
结论:
- 水性多相系统 (MuPSs) 提供稳定,利的密度梯度.
- 这些MuPS可以用于新的分成和分离技术.
- 调整密度步骤的能力为材料分离开辟了新的途径.
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