Adsorptive stripping tensammetry of oxyethylene‐oxypropylene block copolymers

Abstract

The behavior of oxyethylene-oqpropylene block copolymers (OEOPBC) of EPE type was investigated. Most of the investigations were performed with OEOPBC having 30 oxT\propylene subunits and different lengths of oxyethylene chain. The dependences of the peak height on the concentration of surfactant, preconcentration time, and preconcentration potential were examined. OEOPBC partially behave in agreement with the general scheme of the behavior of ethoxylates, formulated on the basis of previous studies and predicting two types of behavior. The scheme has been supplemented with the third type of behavior on the basis of this work: a single peak is formed whose potential is stable, independent of changes of the surfactant concentration, preconcentration time, and potential. All the investigated OEOPBC give peaks suitable for analytical purposes,

Analytical methods for the characterization and determination of nonionic surfactants in cosmetics and environmental matrices

“…Adsorptive preconcentration on the surface of the HMDE enabled the determination of surfactants, this technique being called adsorptive stripping tensammetry (AdST). [120][121][122][123][124][125] The advantage of the use of the HMDE is the ability to differentiate the adsorption of different substances by a change in the preconcentration potential. The main disadvantage of the AdST on the HMDE is the complex behaviour of mixtures of surfactants, which makes direct application to environmental aquatic samples very difficult.…”

The Effect of Alkyl Length on the Analytical Signal of Monoalkylethers of Butylene Oxide‐Ethylene Oxide Block Copolymers in Adsorptive Stripping Tensammetry

“…Accordingly, the behavior of oxyethylated alcohols [1±3], oxyethylated alkylphenols [4], oxyethylene oxypropylene block copolymers [5] and poly(ethylene glycols) [6] under the AdST conditions were investigated. The peak height and peak potential barely follow the theoretically predicted behavior, and therefore, the properties of analytical signals had to be determined experimentally.…”