Observation of micro-topography of newt toe pads and investigating on wet adhesive properties of microstructured surface of PDMS

摘要

The newts (Cynops orientalis) display unique attachment and climbing abilities in wet conditions. The surface microstructure of newt toe pads plays an important role in friction enhancement that ensures fast motion on wet and smooth surfaces. Followed by observing the micro and nanoscale structural features of foot pads of the newts, four micro-patterned surfaces including round pillars, hexagonal pillars and two composite structures were fabricated on Polydimethylsiloxane (PDMS). The static friction and wet-adhesion properties of the microstructured surface of PDMS were measured on the multi-functional surface meter and adhesion equipment, respectively. Effects of micropattern, normal load, wetting condition on static friction properties, and effects of amount of liquid, approach-retraction cycle on adhesion properties were investigated. Our results can give insights into the climbing behavior of newts when they attach and move on wet and smooth surfaces, and possible applications of dense nanopillar arrays on the man-made foot pads for friction enhancement.