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
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