Chapter 2
characterize clay wettability.
Solids which are partially hydrophobic with contact angle θ > 90o (measured
through the water) can also act as emulsifiers to make water-in-oil emulsions
more stable. Figure 2.9 [35] shows the wettability of solids and the types of
emulsions formed by the effect of solids wettability.
water-wet amphiphilic oil-wet
Wettability of solids
oil
water
oil-in-water emulsions
water-in-oil emulsions
Figure 2.9 Wettability of solids and the types of emulsions
For hydrophilic solids, the contact angle is smaller than 90o. The surface of
solids is water-wet and the solids tend to stay in water phase. On the contrary, for
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