论文标题
界面处温度敏感的软凝胶：空气水与油水
Temperature-sensitive Soft Microgels at Interfaces: Air-Water versus Oil-Water
论文作者
论文摘要
可以通过切换外部参数来控制其稳定性的智能乳液或泡沫的形成对基础研究和应用非常感兴趣。一组新兴的智能稳定剂是微凝胶，它们是纳米和微型三维聚合物网络，这些网络被良好的溶剂肿胀。在过去的几十年中，已经研究了各种外部刺激对空气和油水界面上微凝胶二维相行为的影响。但是，几乎没有考虑过顶阶段本身的影响。在这里，我们提供了直接解决顶级对界面微凝胶属性的影响的数据。 PNIPAM微凝胶的尺寸是在两个接口（即空气和脱烷水）中沉积后测量的。尽管微凝胶的总面积随着界面张力的增加而增加，但位于水相中的微凝胶的部分或分数不影响。我们将占据的面积微焦与界面的表面紧张关系相关联，这允许估计弹性模量。与纳米引导测量相比，我们观察到微凝胶的弹性模量更大。通过结合压缩，沉积和可视化，我们表明微凝胶单层的二维相行为并未改变，尽管在较高的界面张力下，微凝胶的平面内大小较大。可以在S.〜Bochenek，A.〜Scotti，W。〜Richtering，\ textit {软物质}，2020，doi：10.1039/d0sm01774d下找到该预印本和电子补充信息的同行评审和扩展版本。
The formation of smart emulsions or foams whose stability can be controlled on-demand by switching external parameters is of great interest for basic research and applications. An emerging group of smart stabilizers are microgels, which are nano- and micro-sized, three-dimensional polymer networks that are swollen by a good solvent. In the last decades, the influence of various external stimuli on the two-dimensional phase behavior of microgels at air- and oil-water interfaces has been studied. However, the impact of the top-phase itself has been barely considered. Here, we present data that directly address the influence of the top-phase on the microgel properties at interfaces. The dimensions of pNIPAM microgels are measured after deposition from two interfaces, i.e., air- and decane-water. While the total in-plane size of the microgel increases with increasing interfacial tension, the portions or fractions of the microgels situated in the aqueous phase are not affected. We correlate the area microgels occupy to the surface tensions of the interfaces, which allows to estimate an elastic modulus. In comparison to nanoindentation measurements, we observe a larger elastic modulus for the microgels. By combining compression, deposition, and visualization, we show that the two-dimensional phase behavior of the microgel monolayers is not altered, although the microgels have a larger total in-plane size at higher interfacial tension. A peer reviewed and extended version of this preprint and the electronic supplementary information can be found under S.~Bochenek, A.~Scotti, W.~Richtering, \textit{Soft Matter}, 2020, DOI: 10.1039/d0sm01774d.
