Biologically inspired reversible adhesives: where are we now?

Abstract

In this report, we demonstrate the adhesive and frictional properties of the first commercial mushroom-shaped adhesive microstructure (MSAMS), which has been inspired by the attachment devices of beetles. It was shown that MSAMS have about twice higher pull-off force compared to a smooth control made from the same material measured on smooth substrates. MSAMS retained their adhesive performance over thousands of attachment cycles and initial adhesive capability could be recovered by washing after being contaminated. In shearing, MSAMS exhibits reduced and stabilized friction in comparison with a smooth control, which demonstrated pronounced stick-slip motion, and shows zero pull-off force in a sheared state, allowing the adhesion to be switched on and off. The presence of oil in the contact zone showed adhesion enhancement on both smooth and rough substrates. All these features lead us to conclude that MSAMS may have practical potential in a variety of applications.