Is the Cassie-Baxter formula relevant?
نویسندگان
چکیده
The utility of the Cassie-Baxter formula to predict the apparent contact angle of a drop on rough hydrophobic surfaces has been questioned recently. To resolve this issue, experimental and numerical data for advancing and receding contact angles are reported. In all cases considered it is seen that contact angles follow the overall trend of the Cassie-Baxter formula, except for the advancing front on pillar type roughness. It is shown that deviations from the Cassie-Baxter angle have a one-to-one correlation with microscopic distortions of the contact line with respect to its configuration in the Cassie-Baxter state.
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ورودعنوان ژورنال:
- Langmuir : the ACS journal of surfaces and colloids
دوره 26 22 شماره
صفحات -
تاریخ انتشار 2010