Performance of some Surfactants as Wetting Agents

Abstract

Abstract The wetting power of anionic surfactant: sodium dodecyl sulfate (SDS), and nonionic surfactants: polyoxyethelene(14)monolaurate [La(EO)14] and polyoxyethelene(14)monooleate [Ol(EO)14] has been studied to determine their performance as wetting agents. The study reveals that the nonionic compound with a long hydrophobic chain exhibits higher wettability than the shorter one when used at very low concentrations (below CMC), and the reverse is shown with high concentrations (above CMC). The wetting power of the investigated surfactants increases as the CMC values increases. In case of the nonionic compounds and at surfactant concentrations equal their CMC values, Ol(EO)14 shows a higher wetting power than La(EO)14 while it possesses a lower HLB value. The anionic surfactant shows an optimum wetting in comparison with the tested nonionic ones. The wettability of all the investigated samples increases as the surface tension of their solutions increases to the allowed limit that can be reached in the presence of surfactant.