Does the Roll-off Angle Depend on Work of Adhesion?

Langmuir. 2022 Apr 26;38(16):4820-4825. doi: 10.1021/acs.langmuir.1c03425. Epub 2022 Apr 12.

Abstract

The roll-off angle of hexadecane droplets was measured on a family of nearly ideal surfaces having similar structures but different interfacial free energies. The variation in interfacial energy was reflected in the contact angles of hexadecane, which provide a measure of the work of adhesion. The hysteresis in the contact angle on these surfaces was low and approximately constant, thereby approximately removing it as a variable and allowing for an assessment of any dependence of the roll-off angle on work of adhesion directly. The results revealed no such dependence, consistent with the descriptions of early researchers in this area.