Simulation of Contact Angle Hysteresis on Chemically Heterogeneous Surfaces

✍ Scribed by Simon Brandon; Abraham Marmur

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 142 KB
• Volume: 183
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1996.0556

✦ Synopsis

available to the drop for overcoming the energy barriers A quasi-steady-state simulation of contact angle hysteresis is which inherently exist between the metastable states.

presented. The model system consists of a two-dimensional drop

The multiplicity of equilibrium states is a necessary condion a smooth but chemically heterogeneous solid surface. The tion for contact angle hysteresis, since (obviously) hysteresis changes in the free energy of the system, the contact angle, and cannot occur if only a single contact angle is possible. This the size of the base of the drop are followed as its volume increases condition, however, is not sufficient. By definition, the pheor decreases. The simulated contact angle hysteresis, including nomenon of hysteresis is observed when a parameter of the discontinuous changes in the contact angle and the size of the base system, such as the volume of a drop placed on a solid, is of the drop, are shown to be very similar to typical experimental varied back and forth. Therefore, contact angle hysteresis observations. In addition, the dependence of receding and advancing angles on the energy available for overcoming energy barriers occurs only if the apparent contact angles depend on the is illustrated.