Contact angle hysteresis on rough hydrophobic surfaces

Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, B224 Evanston, IL 60208-3111, USA
Colloids and Surfaces A Physicochemical and Engineering Aspects (Impact Factor: 2.11). 01/2004; 248:101-104. DOI: 10.1016/j.colsurfa.2004.09.006

ABSTRACT In this short note, we report a quantitative investigation of the hysteresis of the Cassie and Wenzel drops on a given rough surface. The Cassie drop shows much less hysteresis compared to a Wenzel drop and is therefore preferred in applications involving moving droplets. The experimental measurements are compared with the various theoretical models for the apparent contact angles and recommendations are made.

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