Boundary water (solution) as a medium for the spreading of surfactant

Abstract The boundary water (solution), within the electric double layer, has been studied as a medium for the spreading of a surfactant (cetyl alcohol). Neither the electrolyte content of the self boundary solution (variation of KCl concentration from 10 −3 to 1 M ) nor the charge status of the surface (positive charge, i.e.p., negative charge, etc.) exerts any influence on the amount of solution carried by the spreading surfactant. Thus, the boundary solution within the electric double layer, as a medium for the spreading of surfactant, remains unaltered when the surface and the solution charges are altered. This fact leads to two possible conclusions: (a) not the whole boundary solution is structured; and (b) the structure is exposed to destruction by the surface pressure (≈35 dyn cm −1 ) of the spreading surfactant.