title: Characterization for Cassie-Wenzel wetting transition based on the force response in the process of squeezing liquid drops by two parallel superhydrophobic surfaces.
abstract: Application of superhydrophobic surfaces is partly limited by the escaping of the entrapped air beneath the liquid sitting on the superhydrophobic surfaces, i.e., the so-called Cassie-Wenzel wetting transition. Here, to characterize this wetting transition, a linear force response relation with certain abnormal systematic deflection showing the wetting transition information is constructed for the process of squeezing the test liquid drop by two parallel structured (superhydrophobic) surfaces. The linear force response relation is validated by replotting the experimental data from the former work. And then the wetting transition information is investigated on a numerically generated force response curve with certain errors by taking into account the liquid pressure variation during the wetting transition. Results show that the wetting transition can cause an obvious bulge on the linear force response curve. We believe that this method has a potential application in characterizing the robustness of superhydrophobic surfaces.
authors.affiliation: School of material science and engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Li