The electrophoretic mobilities of silver iodide sol particles
have been measured as a function of pAg in the presence of var,ious
concentrations of C5, C8, C10, C12 and C14 sodium alkyl sulfonates
at constant ionic strength and temperature. Contact angles in the
solid-air-solution system both in the absence and in the presence
of the C14 sulfonate have also been determined. These results have
been compared with previously reported work on the effect of
alkyl sulfonates on the electrokinetic and wetting behavior of alumina.
Application of the Stern-Grahame model of the electrical
double layer allows delineation of the various mechanisms contributing
to the adsorption phenomena. In the case of the aluminasulfonate
system the adsorption process is purely physical, viz.
electrostatic and hydrocarbon chain-chain interactions, while for
the AgI-sulfonate system both physical and chemical processes are
involved, viz. electrostatic, hydrocarbon chain-solid, chain-chain,
and solid-polar head interactions
