Inclusion of structural forces in the theory of stability of colloids and films

On the basis of an analysis of the experimental and theoretical data, the parameters of an exponential isotherm of the structural component of disjoining pressure for liquid interlayers and films are found. Inclusion of the isotherm of structural forces, II s ( h ), in the DLVO theory and the heterocoagulation theory permitted to explain the phenomena of stability and the reversible coagulation of the hydrophilic sols of silica, as well as to plot the isotherm of disjoining pressure of the wetting aqueous films on the quartz surface, II( h ). Using Frumkin-Derjaguin's equation and theoretical isotherms, II( h ), as the basis, the values of contact angles are calculated. The methods for controlling the wetting, which is due to a change in the contribution of different components of long-range surface forces to the II( h ) isotherm of wetting films, are considered.