Topography driven spreading.
Roughening a hydrophobic surface enhances its nonwetting properties into superhydrophobicity. For liquids other than water, roughness can induce a complete rollup of a droplet. However, topographic effects can also enhance partial wetting by a given liquid into complete wetting to create superwetting. In this work, a model system of spreading droplets of a nonvolatile liquid on surfaces having lithographically produced pillars is used to show that superwetting also modifies the dynamics of spreading. The edge speed-dynamic contact angle relation is shown to obey a simple power law, and such power laws are shown to apply to naturally occurring surfaces.
McHale
G
G
School of Biomedical and Natural Sciences, The Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom. glen.mchale@ntu.ac.uk
Shirtcliffe
N J
NJ
Aqil
S
S
Perry
C C
CC
Newton
M I
MI
D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D013499:Surface Properties; D017155:Wettability