Dedication

Dotchi Exerowa. Foams Stabilized by Hydrophobically-modified Inulin Polymeric Surfactant

“…Several factors affect the foam lifetime, of which the following can be mentioned: (i) adsorption of surfactant at the air/water interface; (ii) formation of black film [ 1 ]. Both of these factors are affected by the nature of the surfactant and the electrolyte concentration.…”

“…This concentration has been named as C el, cr to denote the transition concentration from common thin films to black films, i.e. the transition from electrostatic to steric stabilization [ 1,2 ].…”

“…A correlation between single foam films and real foams can be drawn only when the experimental conditions with respect to capillary pressure, film thickness and bubble radius, temperature, etc., are kept very close. Two techniques have been developed to meet this requirement: the Foam Pressure Drop Technique (FPDT) that allows one to apply specific (pre-determined) capillary pressure in the foam liquid phase to measure the foam lifetime at constant pressure [ 1,6,7 ] and the Film Pressure Balance Technique (FPBT), that allows one to determine the disjoining pressure/film thickness isotherms [ 1,[8][9][10] ]. This enables us to conduct comparisons between foam films and foams at equal capillary pressures [ 1,[8][9][10] ].…”

“…The single foam films were investigated with FPBT, which was described in detail in [ 1,2,[8][9][10] ]. Briefly, with this technique a pressure can be applied to the film and the corresponding film thickness h is measured interferometrically, so that one obtains the disjoining pressure Π as a function of the film thickness h. From the resulting Π/h curves it is possible to estimate the stabilising surface forces acting in the film [ 1, 2, 6, 10 ].…”

“…FPBT also enables to determine the critical pressure of single foam film rupture (the maximum pressure the films can resist). It was determined by smooth increase of pressure in the measuring cell up to film rupture [ 1,11 ].…”