Interfacial dynamics and structure of surfactant layers

Adsorption at the liquid/liquid interface in mixed systems with hydrophobic extractants and modifiers

“…Similar relations between the values of diffusion coefficient and the bulk surfactant concentration have also been observed once by other authors for non-ionic surfactants in the hydrocarbon/water systems [1,[10][11][12][13][14][15][16] and air/water [17][18][19]. The lower values of diffusion coefficients for higher concentration could be explained by increase of aggregates concentration in more concentrated solutions due to the association process [20]. On the other hand with increase of the bulk concentration the mass transport could change due to modification of adsorption process from pure diffusion to activation-diffusion [20,21].…”

“…The lower values of diffusion coefficients for higher concentration could be explained by increase of aggregates concentration in more concentrated solutions due to the association process [20]. On the other hand with increase of the bulk concentration the mass transport could change due to modification of adsorption process from pure diffusion to activation-diffusion [20,21].…”

Aggregation behavior of Triton X-114 and Tween 80 at various temperatures and concentrations studied by density and viscosity measurements

“…5 as an example). On the a = f(log C) curves for TX114 and Tween 80 at T = 293 K, there are two break points-the first corresponds to the values of CMC determined from the surface tension measurements and the second is close to C = 10 -3 M. This suggests the existence of the second value of CMC of TX114 and Tween 80 in which the micelle structure changes and/or admicelles are changed into micelles [28]. It is known that amphiphilic molecules generally form spherical aggregates in aqueous solutions above the CMC, but, under certain conditions these spherical micelles grow in size or change their shape resulting in the formation of rodlike structures or even long flexible micelles [29][30][31][32][33].…”

“…3 and 4 for the studied surfactants at C higher than 10 -3 M, there is almost a linear increase in u V values with T, which suggests significant structural changes in the studied surfactant micelles with the increasing temperature and/or changes in the intermolecular interactions occurring between surfactants and water. These interactions can be described, among others, from the values of the volume expansivity, a, also known as the coefficient of thermal expansion, which is a measure how the volume changes with the temperature [18,28]. For both surfactants, the calculated values of a increase with the rise in T, but the relationship between a and log C for a given surfactant and temperature is more interesting (Fig.…”

Water displacement by surfactant solution: an experimental study to represent wastewater loss from sewers to saturated soil

“…The rate of surfactant adsorption at interface is controlled by the transportation step of monomers to the near-interface region. This is basically driven by molecular diffusion (Macleod and Radke 1993) additionally then from the near-interface region to the interface, electrostatic charge becomes dominant (Zhmud and Tiberg 2005).…”