Surfactants and self-assembly systems

We focus our research on the determination of adsorption properties of surfactants and their complexes with polymers (natural-proteins or polysaccharides or synthetic, cationic and anionic polyelectrolytes) at liquid interfaces: water/air or water/oil.

MAIN RESEARCH TOPICS

  • Adsorption properties of ionic surfactants
  • Cleavable surfactants of "esterquat" or "amidoquat" type as emulsifiers/ nanoemulsions stabilizers
  • Influence of molecular structure on cleavable surfactants hydrolysis rate
  • Influence of surfactants adsorption kinetics on foam film stability
  • Application of self assembly systems in conservation and restorations of mural paintings

METHODS

  • Surface tension measurements by drop shape analysis method (adsorption kinetics from 10 s to a few hours)
  • Dynamic surface tension measurements using the maximum bubble pressure method (adsorption kinetic from 0.01s to 40 s)
  • Contact angle measurements

MAIN ACHIEVEMENTS

  • Explanation of high surface activity of "esterquat" type surfactants by synergistic effect between pH depended hydrolysis in the bulk solution and simultaneous adsorption of surfactants, surface active products of hydrolysis and their complexes.
  • Selection of emulsifiers with stable surface charge enabling formation for stabilization of nanoemulsions. Drops of emulsions can be treated as cores for the layer by layer formation of polyelectrolyte shell with different thickness, permeability and function dependent on active substances inside those nanocontainers and their potential applications.
  • Explanation of the pH regulated surface activity of alkanoic acids on the basis of theoretical model of adsorption of ionic- nonionic surfactants mixtures.
  • Explanation of how the surface activity of cationic surfactants depends on the concentration and type of electrolyte counterions (Hofmeister effect in ionic surfactant solutions).