Transparent coatings for everyday applications
Water droplets run off the leaf surface: In nature, this phenomenon is mainly known from lotus plants. Researchers imitate this lotus effect by means of superhydrophobic i.e., highly water-repellent, surfaces.
Insensitive to abrasion
At Karlsruhe Institute of Technology (KIT), scientists develop a new class of such materials. They combine the properties of fluoropolymers i.e., plastics with a degree of fluorination, with the roughness known from lotus leaves. In this way, they obtain surfaces that are both oil- and water-repellent. The new materials are characterised by a high chemical and thermal stability. The researchers succeeded for the first time in developing a fluorinated polymer foam which, in addition, is transparent and insensitive to abrasion. This material, called “Fluoropor”, is introduced in Nature Scientific Reports.
Ideally suited as coating for glass
Superhydrophobic properties develop due to structuring on the nano/microscale. Such extremely fine structures make surfaces highly sensitive to abrasion and account for the fact that they are not sufficiently robust for everyday applications. In the case of “Fluoropor”, in contrast, the nano-/microstructure is not limited to the surface but occurs throughout the material, thus giving the material a high long-term abrasion resistance and suitability for daily use. The foam seems optically transparent due to its tiny pores whose diameter is below the wavelength of visible light. It, therefore, is ideally suited as a coating for transparent substrates such as glass. The material, can, however, also be applied to e.g., metal, polymers, or textiles.
Manufactured by radical polymerisation
Fluoropor can be efficiently manufactured in one step in different thicknesses by so-called photo-induced radical polymerisation. The development is funded by the Federal Ministry of Education and Research within the program “NanoMatFutur”.