What Does Sessile Drop Method Mean?
The Sessile drop method is performed with an optical tensiometer to determine the contact angle of a liquid on a surface. It is the standard arrangement for optical measurement of contact angle. A liquid sample is placed on a surface using a syringe. The inter-molecular forces of cohesion and adhesion determine the contact angle created.
When the contact angle is less, the adhesive forces are stronger and the liquid molecules interact more with the solid molecules than the liquid ones. When the contact angle is large, the cohesive forces are stronger and the liquid molecules interact more among themselves than with the solid molecules.
