Dynamic behavior of water droplets on flexible, adaptive and switchable surfaces generated using surface attached polymer networks and brushes

• Applicant: Professor Dr. Jürgen Rühe
• Subject Area: Synthesis and Properties of Functional Materials ; Polymer Materials
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 422793161

The overarching goal of the research project within the Priority Program is to generate substrate surfaces with a tailor-made chemistry and topography which can respond dynamically to changes in the environment and to study the wetting behavior of simple liquids on such reconfigurable surfaces. We will aim to obtain a deeper insight into dynamics of wetting as well as dewetting of such liquids on switchable/ substrates. We will focus primarily on experimental methods but will also combine results with theoretical analyses in collaboration within the priority program. We will follow essentially two concept lines: 1. We will generate substrates where a specific surface topography is chosen and the surface chemistry is adjusted to allow dynamic changes through e.g. isomerization reactions which allow to change the surface energy and thus the wetting behavior in a dynamic way. 2. We will generate substrates, where a certain surface chemistry is chosen and the surface is made reconfigurable through microengineering tools, eg. the surface topography is systematically switched from smooth to rough through an external stimulus or where the surface is becoming deformed in the course of liquid contact. In some cases the switching process will be induced by the wetting liquid itself so that responsive/adaptive surfaces are obtained. Towards the end of the funding period the two lines will be brought together either by generating multiple-stimulus responsive surface, where one stimulus acts on the surface chemistry/ surface polarity and one on the topography. In other cases it is envisioned to use the developed technologies as a toolbox, where features of the surfaces in the two project lines (stimulus responsive surface chemistry and stimulus responsive topography) are combined to generate dynamically reconfigurable surfaces, where the dynamic changes have a very strong impact on the wetting behavior.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2171: Dynamic wetting of flexible, adaptive and switchable surfaces
• Co-Investigator: Dr. Oswald Prucker