Researchers in the US have attempted to surpass nature and create a synthetic material that sticks to surfaces at the nanometre level.
Researchers in the US have attempted to surpass nature and create a synthetic material that sticks to surfaces at the nanometre level with remarkable strength, by imitating the mechanism that allows the gecko to climb a vertical surface.
Geckos have tiny elastic hairs covering their feet that allow them to stick to almost any surface. Ali Dhinojwala and colleagues at the University of Akron and the Rensselaer Polytechnic Institute used this idea and added multiwalled carbon nanotubes (MWNTs) to the surface of a polymer. The MWNTs work in the same way as the tiny hairs, allowing the polymer to stick to different surfaces.
As a result of the MWNTs’ rough surface and unusual flexibility, their adhesive strength is 200 times that of gecko foot hairs. Dhinojwala suggests that this superiority will open doors for future applications. ’Perhaps these structures can also be used as dry adhesives in space or microelectronic applications,’ he said.
But there is still some way to go before the secret of nature’s glue is truly unravelled. Geckos have evolved over centuries to perfect how they attach and remove their feet effortlessly from surfaces, and Dhinojwala admits that the mystery of how to achieve this synthetically has yet to be solved. ’It will be a challenge to figure out how to design a strong adhesive that can provide a strong attachment to support a large force but at the same time have the capability of detaching itself from the surface with ease,’ he said.
B Yurdumakan et al, Chem. Commun., 2005, 3799 (DOI: 10.1039/<MAN>b506047h</MAN>)