Coagulation contacts adhesive force

The strength of a coagulation contact, i.e., adhesive force between particles, is determined primarily by molecular forces. For spherical particles, in agreement with eq. (VII. 13), this force is given by... 

Figure 19.10. Illustrations of the effects of hydrophobic interactions, i. e. the tendency to eliminate contacts between water and nonpolar molecules or surfaces (a) water and oil are immiscible, with a strong driving force to expel hydrocarbon molecules from water (b) self-assembly of surfactant molecules (c) other types of association of hydrocarbon chains (d) folding of proteins (e) strong adhesion between non-polar surfaces in water (f) non-wetting of water on hydrophobic surfaces (g) rapid coagulation of hydrophobic particles in water (h) attachment of hydrophobic particles to air bubbles (mechanism of froth flotation). (Redrawn from J. Israelachvili, Intermolecular and Surface Forces, with Applications to Colloidal and Biological Systems, Academic Press, London, 2nd Edn, 1991)...

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