contact angle

[malaisamy]

hi colleagues, when the contact angle is measured for a membrane, the value we receive in sessile drop and in captive bubble are entirely different from each other. why? thanks for your answer.

 

[masuk]

Well for a sessile drop (say, liquid A) the surrounding atmosphere is (generally) air; for captive bubble the surrounding is not air for sure...............

It also partially depends on the size or volume of your drop.

You have to be careful about the test conditions and probing liquid for any contact angle data interpretations!