Polymer-mediated interactions of fluid membranes in a lyotropic lamellar phase: a small angle X-ray and neutron scattering study
Groupe de Dynamique des Phases Condensées (UMR UMII/CNRS 5581) , C.C. 26,
Université Montpellier II 34095 Montpellier Cedex 5, France
Published online: 15 May 1999
Small angle X-ray and neutron scattering data on an effective three-component lamellar phase composed of water, a non adsorbing water-soluble polymer (polyvynilpyrolidone), fluid membranes, made from a mixture of a cationic surfactant (cetylpiridiumchloride) and a cosurfactant (hexanol), are presented for various membrane as well as polymer concentrations. The data are fitted with a recently proposed model which takes into account the geometry and the fluctuations of these periodic structures. This allows a quantitative study of the polymer contribution to the smectic compression modulus of the lamellar phase. Four different regimes of polymer confinement are expected. The associated variations in are compared to a recent theoretical model, which predicts the polymer-mediated contribution to the smectic compression modulus.
PACS: 61.30.Eb – Experimental determinations of smectic, nematic, cholesteric, and other structures / 82.70.-y – Disperse systems / 61.25.Hq – Macromolecular and polymer solutions; polymer melts; swelling
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999