Factors Affecting Contact Angle and Wettability

[@muhammadarslan44]

very helpful

[@PolymerWorld]

Thanks for the feedback.

[@daithiod]

Good video. Nicely explained. I can’t understand the thumbs down.

[@vaibhavkachare2776]

pleaseMake video on GATE polymer science and technology especially on the properties of polymer....

[@PolymerWorld]

Sure! We will upload videos soon.

[@maryemoubella8798]

Please, I have a question, what is the difference between wetting energy and surface energy? is there any difference?

[@PolymerWorld]

Surface energy is the intrinsic property of the material but wetting energy will depends on the relative interaction between two surfaces.

[@AcidArmy_]

⁠@@PolymerWorldhow could you describe a liquid’s wetting energy in contact with itself?

[@ayah_sawaie]

Can you please add a subtitles?

[@gadgetsreview3619]

i have no idea why increase of surface toughness leads to better wettability. and why higher surface roughness means lower contact angle, can you please explain?

[@PolymerWorld]

During the wetting process of rough solid surfaces, the liquid does not completely enter the surface gaps leaving amount of air under the droplets. As you know, air consists of mainly oxygen and nitrogen. Atomic oxygen has high tendency to bonding with water molecules forming hydrogen bonding as well as with something else that have similar properties to water. In hydrophilic surface trapped air reduces contact angle and increases wettability.

[@maryemoubella8798]

I did an experiment on ABS plastic, the contact angle of smooth ABS plastic is around 70° which means hydrophilic surface, but when I treated the surface of this plastic by grinding using sandpaper 240um and 400um, the contact angle of the ABS plastic grounded is more than 90° ''around 100°", which mean the surface become hydrophobic. So, how can you explain these results ?!! and thank you so much. @@PolymerWorld