Ambient Climate Influences Anti-Adhesion between Biomimetic Structured Foil and Nanofibers

Nanomaterials, vol. 11, pp. 3222

Abstract

Due to their uniquely high surface-to-volume ratio, nanofibers are a desired material for various technical applications. However, this surface-to-volume ratio also makes processing difficult as van der Waals forces cause nanofibers to adhere to virtually any surface. The cribellate spider Uloborus plumipes represents a biomimetic paragon for this problem: these spiders integrate thousands of nanofibers into their adhesive capture threads. A comb on their hindmost legs, termed calamistrum, enables the spiders to process the nanofibers without adhering to them. This anti-adhesion is due to a rippled nanotopography on the calamistrum. Via laser-induced periodic surface structures (LIPSS), these nanostructures can be recreated on artificial surfaces, mimicking the non-stickiness of the calamistrum. In order to advance the technical implementation of these biomimetic structured foils, we investigated how climatic conditions influence the anti-adhesive performance of our surfaces. Although anti-adhesion worked well at low and high humidity, technical implementations should nevertheless be air-conditioned to regulate temperature: we observed no pronounced anti-adhesive effect at temperatures above 30 °C. This alteration between anti-adhesion and adhesion could be deployed as a temperature-sensitive switch, allowing to swap between sticking and not sticking to nanofibers. This would make handling even easier.

Authors 5

1. Marco Meyer corresponding Aachen Institute for Biology II

   RWTH Aachen University

   Affiliation as printed

   Institute for Biology II, RWTH Aachen, Worringerweg 3, 52074 Aachen, Germany

2. Gerda Buchberger

   Johannes Kepler University of Linz

   Affiliation as printed

   Institute of Applied Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria

3. J. Heitz

   Johannes Kepler University of Linz

   Affiliation as printed

   Institute of Applied Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria

4. Dariya Baiko

   Johannes Kepler University of Linz

   Affiliation as printed

   Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria

5. Anna‐Christin Joel corresponding Aachen Institute for Biology II

   RWTH Aachen University

   Affiliation as printed

   Institute for Biology II, RWTH Aachen, Worringerweg 3, 52074 Aachen, Germany