一种物理方法,专门提高烯液滴的流动性
Dalton F Cheng1, Chihiro Urata, Benjamin Masheder
1National Institute of Advanced Industrial Science and Technology, 2266-98, Anagahora, Shimoshidami, Moriyama-ku, Nagoya, Aichi 463-8560, Japan.
Journal of the American Chemical Society
|June 1, 2012
概括
研究人员使用聚二甲基 (PDMS) 刷膜对表面的液滴运动进行了控制. 降低聚合物分子重量和探测液体表面张力降低了阻力,使液滴运动更容易.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 聚合物科学 聚合物科学
背景情况:
- 控制液体-基板相互作用对于各种应用至关重要.
- 聚合物刷膜提供可调的表面性能.
- 了解影响液滴流动性的因素对于表面设计至关重要.
研究的目的:
- 为了证明对液滴运动阻力在表面上的无控制.
- 为了研究聚合物分子重量的影响,并探测液体特性对液滴流动性的影响.
- 评估不同的方法来计算动态潮湿的接触角歇斯底里.
主要方法:
- 使用了具有不同分子量的化线性聚二甲基素 (PDMS) 刷膜.
- 采用接触角 (CA) 歇斯底里和倾斜角测量来评估液滴运动阻力.
- 研究的探头液体包括水,n-hexadecane,n-dodecane和n-decane.
- 使用标准 (Δθ) 和位修正 (Δθ(cos)) 方法计算CA歇斯底里.
主要成果:
- 通过调整PDMS分子重量和探测器液体表面张力,成功控制了液滴运动阻力.
- 较低的聚合物分子重量和较低的探测液表面张力导致液滴运动的阻力下降.
- 水滴的流动性随着聚合物分子重量的增加而降低,而n-decane滴显示出最小的阻力.
- 经过正的CA歇斯底里斯 (Δθ(cos)) 提供了一个更有利的估计动态潮湿行为.
结论:
- 对于极性和非极性液体,PDMS刷膜可以调节控制液滴运动阻力.
- 聚合物链的移动性受到分子量和胀的影响,是控制液滴运动的关键.
- 选择接触角歇斯底里计算方法会影响动态湿过程的准确评估.
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