Dynamic surface properties of polyethylenimine and sodium dodecylsulfate complex solutions

Measurements of the concentration and adsorption time dependencies of the dynamic surface elasticity of mixed polyethylenimine/sodium dodecyl sulfate (PEI/SDS) solutions show transitions between a few states of different surface elasticity. In the range of low surface pressures the elasticity is governed by the branched structure of the macromolecules, while at high surface pressures the elasticity exhibits a behaviour typical for other polyelectrolyte/surfactant surface layers.