https://doi.org/10.1007/s100510050516
Mixed monolayers of cationic surfactants and anionic polymers at the air-water interface: Surface tension and ellipsometry studies
1
Laboratoire de Physique des Matériaux Divisés, Université de Marne la Vallée (IFI) 2,
Cité Descartes,
Champs-sur-Marne, 77454 Marne la Vallée, Cedex 2, France
2
Laboratoire de Physique des Solides, Bâtiment 510, Université Paris Sud, 91405 Orsay,
France
3
Institut Français du Pétrole, 1 Avenue de Bois-Préau, 92852, Rueil Malmaison, France
Corresponding author: a langevin@lps.psud.fr
Received:
16
October
1997
Revised:
14
May
1998
Accepted:
15
May
1998
Published online: 15 October 1998
Equilibrium surface tension measurements have been carried out on mixed solutions of a non- surface active polyelectrolyte (polyacrylamide sulfonate) and cationic surfactants. A strong synergistic lowering of the surface tension is found in the concentration range where no appreciable complexation of surfactant and polymer occurs in the bulk solution (as seen from viscosity measurements). The surface tension decrease does not depend upon the polymer molecular weight, and there is a limited influence of the surfactant chain length. The influence of the degree of charge of the polymer is more important: for small degree of charge, the complexation is less cooperative, and the structure of the surface complex is looser.
PACS: 68.10.Cr – Surface energy (surface tension, interface tension, angle of contact, etc.) / 78.66.Sq – Composite materials / 82.70.Gg – Gels and sols
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998