In many industrial applications such as froth flotation, foams and emulsions, the interactions between solid and deformable interfaces, or two deformable interfaces, is of critical importance. Understanding these micro-scale interactions is vital for the prediction and control of the macro-scale behaviour. The understanding of the dynamic interactions when one or more surfaces is “soft”, and thus the overall interaction may be dominated by surface deformations, is of particular interest. Recent advances within the Particulate Fluids Processing Centre has enabled the modeling of atomic force microscope (AFM) force data collected for the static¹ and dynamic interactions^2,3 between a solid sphere and a deformable interface, or two liquid droplets. Here we present data examining the effect of the particle/droplet size ratio and the bulk phase solution viscosity on the interaction between silica spheres and sodium dodecyl sulfate (SDS) stabilised tetradecane droplets. In particular, this data enables us to probe the existence, or otherwise, of a slip boundary between the two interacting surfaces. Force-distance profiles collected from AFM experiments are compared to theoretical profiles in which different slip lengths are incorporated.

References

(1)       Dagastine, R. R.;  Stevens, G. W.;  Chan, D. Y. C.; Grieser, F. Journal of Colloid and Interface Science 2004, 273, 339-342.

(2)       Carnie, S. L.;  Chan, D. Y. C.;  Lewis, C.;  Manica, R.; Dagastine, R. R. Langmuir 2005, 21, 2912-2922.

(3)       Dagastine, R. R.;  Manica, R.;  Carnie, S. L.;  Chan, D. Y. C.;  Stevens, G. W.; Grieser, F. Science (Washington, DC, United States) 2006, 313, 210-213.