Huang Shilin, Gawlitza Kornelia, von Klitzing Regine, Gilson Laurent, Nowak Johannes, Odenbach Stefan, Steffen Werner, Auernhammer Günter K
Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany.
Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, 10623 Berlin, Germany.
Langmuir. 2016 Jan 26;32(3):712-22. doi: 10.1021/acs.langmuir.5b01438. Epub 2016 Jan 11.
Stimuli-responsive microgels can be used as stabilizers for emulsions. However, the details of structure and the viscoelastic property of the microgel-laden interface are still not well-known. We synthesized fluorescently labeled microgels and used confocal microscopy to observe their arrangement at the water/oil interface. The microgels aggregated spontaneously at the interface, and the aggregated structure reorganized due to thermal motion. The structure of the interfacial layer formed by microgels depended on the microgel concentration at the interface. We suggest that the structure was controlled by the aggregation and adsorption of microgels at the interface. The interparticle separation between microgels at the interface decreased over time, implying a slow aging process of the microgels at the interface. Magnetic beads were introduced at the interface and used to trigger deformation of the microgel layer. Under compression and shear the microgels in the aggregated structure rearranged, leading to plastic deformation, and some elastic responses were also observed.
刺激响应性微凝胶可作为乳液的稳定剂。然而，负载微凝胶的界面的结构细节和粘弹性仍然不太清楚。我们合成了荧光标记的微凝胶，并使用共聚焦显微镜观察它们在水/油界面的排列。微凝胶在界面处自发聚集，并且聚集结构由于热运动而重新组织。由微凝胶形成的界面层的结构取决于界面处的微凝胶浓度。我们认为该结构是由微凝胶在界面处的聚集和吸附控制的。界面处微凝胶之间的颗粒间间距随时间减小，这意味着微凝胶在界面处的老化过程缓慢。在界面处引入磁珠并用于触发微凝胶层的变形。在压缩和剪切作用下，聚集结构中的微凝胶重新排列，导致塑性变形，并且还观察到一些弹性响应。
