In a hypothetical scenario, wherein a grad student becomes obsessed with determining the exact contact angle of a hydrophilic surface.. how would you go about doing so?
This grad student has attempted the usual methods (using the goniometer, varying the liquids and such), but is dissatisfied by the ridiculous complexity of the scenario (The grad student really does not want to assume the angle is zero). She would like to stretch her brain cells and discuss this hypothetical contact angle problem with people who may (or may not) have opinions on the matter. Perhaps these persons could put their heads together and come up with a relatively simple solution?
Please feel free to be humorous.
What material is your surface made of ?
What models have you tried to use to compute the CA with the Goniometer mesurements ??
Regards ! :)
If I get it right, you're claiming that you're measuring a contact angle of nearly zero for a hydrophilic surface when wetting with different test liquids? I agree with Paresh that it would be interesting to know which test liquids were used, because their polar and disperse components have a crucial role on the wetting behavior. In case you want to compare different hydrophilic surfaces with the same available test liquids and always observe a contact angle of nearly zero, then it would be interesting to measure the contact angle over the time and compare how the liquid drop spreads on the different surfaces. However, you should know that measuring the contact angle in order to determine its polar and dispersive components is a very theoretical method used in laboratory experiments. The surface might behave different when being used under real conditions.
You might want to check this method developed by Prof. Jeffrey S Allen ,
"An analytical solution for determination of small contact angles from sessile drops of arbitrary size".
www.sciencedirect.com/science/article/pii/S0021979703001279
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