Collect. Czech. Chem. Commun. 1991, 56, 78-84

Stable layers of oxyethylated alcohols adsorbed on the surface of a hanging mercury drop electrode under tensammetric conditions

M. Krystyna Pawlak

Institute of Chemistry, Technical University of Poznan, 60-965 Poznan, Poland


The stability of adsorbed layers on a hanging mercury drop electrode was examined for oxyethylated alcohols ( 18-14, 18-10, 18-6, 10-14 and 6-14 where the first number denotes the number of carbon atoms in the n-alkyl chain and the second, the number of oxyethylene sub-units), Triton X-100 and for 18-14/10-14 and 18-14/Trriton X-100 mixtures. The film stability was assessed in terms of the number of repetitions of the tensammetric peak recorded at the mercury drop after 5 or 10 min of adsorptive preconcentration. The most stable film is formed by the polyoxyethyleneoctadecyl monoethers, both alone and in the mixtures studied. The films are broken down by vigorous stirring of the solution for a certain time applying an electrode potential above the adsorption range of the surfactants.