Berlin 2005 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 23: Polymer films I
CPP 23.1: Vortrag
Dienstag, 8. März 2005, 14:00–14:15, TU C130
Interactions between polyelectrolytes and monovalent ions in adsorbed nanofilms — •Regine v. Klitzing1,2 and John Erik Wong3 — 1MPI f. Kolloid- und Grenzflächenforschung, Potsdam — 2Institut f. Physikalische Chemie, CAU Kiel — 3Stranski-Laboratorium, TU Berlin
The polymer films presented in this study were made by alternate adsorption of polyanions and polycations from aqueous solution onto solid substrates (Silicon, glass) using the layer-by-layer method developed in the early 1990s by Decher et al.[1]. It is assumed that complexes between polyanions and polycations are formed by an exchange of small counterions. In the present work it is shown that not only the ionic strength [2, 3] but also the type of low molecular salt has a pronounced effect on the formation and destruction of the polyelectrolyte multilayers. The different ions lead to a systematic change in film properties according to the Hofmeister Series. This means that specific interactions due to the polarizibility and the related hydration shell of the ions are important for the multilayer structure. The multilayers are characterized by ellipsometry, X-ray reflectometry and AFM.
[1] G. Decher, J.D. Hong, J. Schmitt (1992) Thin Solid Films 210/211, 831.
[2] R. Steitz, W. Jaeger, R. v. Klitzing (2001) Langmuir 17, 4471.
[3] U. Voigt, W. Jaeger, G. H. Findenegg, R.v.Klitzing (2003) J. Phys. Chem. B., 107, 5273.