Superhydrophobic polymer‐particle composite films produced using various particle sizes
Superhydrophobic polymer‐particle composite films produced using various particle sizes
复制标题
DOI：
10.1002/sia.4930
复制
发表时间：
2012-07
影响因子：
1.7
通讯作者：
I. Karapanagiotis;P. Manoudis;A. Savva;C. Panayiotou
中科院分区：
文献类型：
--
作者：
I. Karapanagiotis;P. Manoudis;A. Savva;C. Panayiotou
将亲水性氧化铝（Al 2 O3）纳米颗粒（25、35和150 nm）以不同浓度分散在市售疏水性聚（烷基硅氧烷）（Silres BS-290）的溶液中，并将悬浮液喷涂在玻璃表面上。在由稀分散体制备的硅氧烷-纳米颗粒复合膜表面上测量的静态接触角（θS）随颗粒浓度迅速增加。由浓分散体制备的复合膜具有最大的常数θS（饱和时θS为160°），它不受颗粒尺寸的影响。这些膜还表现出非常小的接触角滞后（5°），这也与颗粒尺寸无关。因此，相同的超疏水特性可以在使用纳米颗粒的硅氧烷膜中诱导，纳米颗粒的范围可以从几纳米到几十纳米。然而，颗粒尺寸和更准确地说，颗粒比表面积显著地影响最小临界颗粒浓度，其必须用于分散体中以在复合膜表面上诱导超疏水性，即达到θS = 150°。结果表明，临界颗粒浓度与比表面积呈指数关系下降。这一结果对于有兴趣对复合膜的润湿性进行良好控制的超疏水表面的制造商来说是重要的。版权所有© 2012约翰威利父子有限公司.
Hydrophilic alumina (Al2O3) nanoparticles (25, 35, and 150 nm) are dispersed in different concentrations in solutions of a commercial hydrophobic poly(alkyl siloxane) (Silres BS‐290), and the suspensions are sprayed on glass surfaces. Static contact angles (θS), measured on surfaces of siloxane‐nanoparticle composite films that were prepared from dilute dispersions, increase rapidly with particle concentration. Composite films prepared from concentrated dispersions exhibit a maximum, constant θS (at saturation θS is 160°), which is not affected by the size of the particles. These films exhibit also very small contact angle hysteresis (5°), which is also independent of the particle size. Consequently, the same superhydrophobic character can be induced in siloxane films using nanoparticles, which can range from a few up to several tenths of nanometers. However, the particle size and more precisely the particle specific surface area affects dramatically the minimum critical particle concentration, which must be used in the dispersions to induce superhydrophobicity on the surface of the composite films, that is, to achieve θS = 150°. It is shown that critical particle concentration decreases exponentially with specific surface area. This result can be important for manufacturers of superhydrophobic surfaces who are interested in having a good control on the wettability of the composite films. Copyright © 2012 John Wiley & Sons, Ltd.