PENETRATION OF AQUEOUS SURFACTANT SOLUTIONS INTO THIN HYDROPHOBIZED CAPILLARIES

Three mechanisms of the penetration of surfactant solutions into hydro phobized capillaries are possible. The first takes place at high conce ntrations C-0 > CMC. Spontaneous penetration corresponds to a high rat e, but is limited to some finite length. The second mechanism is reali zed when C-0 < CMC. The rate of penetration in this case is much lower , and is controlled by the reduced concentration C-m at the meniscus. At an even lower concentration, the diffusion mechanism of penetration takes place. The rate of penetration is determined here by the surfac e diffusion of surfactant molecules in front of the meniscus. Forced a bsorption is not effective, since, as a result of adsorption, the surf actant molecules cannot reach the surface of the advanced meniscus.