Review on Kinetics of Spreading and Wetting by Aqueous Surfactant Solutions - Drops and Bubbles in Contact with Solid Surfaces - page 45

Figure 5. Spreading of surfactant solution over hydrophobic substrate [32]. Adsorption of surfactants
on a bare hydrophobic substrate, s (t) , is shown in the left hand side. The latter results in the increase
of the solid-vapour (gas) interfacial energy, γ sv (t) .
Figure 6. Time evolution of the spreading of a water drop (aqueous SDS solution c = 0 . 05%,
2 . 5 ± 0 . 2 µl volume) over PTFE wafer. Error bars correspond to the error limits of video evaluation of
images (pixel size) [32].
Figure 7. Fitted dependency of τ on SDS surfactant concentration inside the drop (spreading over
PTFE wafer). Error bars correspond to the experimental points scattering in different runs; squares are
average values [32].