Regensburg 2013 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 33: Poster: Charged Soft Matter
CPP 33.12: Poster
Wednesday, March 13, 2013, 16:30–18:30, Poster C
Polyelectrolyte Multilayers (PEM) of different charge densities in humid atmospheres: Structural changes and swelling mechanics — Ingo Dönch1, Patrick Ott2, André Laschewsky2, Andreas Fery3, Rumen Krastev4, and •Ralf Köhler1,5 — 1Interfaces, MPI-KGF Potsdam/Golm — 2Applied Polymer Chemistry, University of Potsdam — 3Physical Chemistry II, University of Bayreuth — 4Biomaterials, NMI at University of Tübingen — 5Soft Matter and Functional Materials, HZB Berlin: Germany
PEM consist of complexed layers of two organic polyions of opposite charge build-up by layer-by-layer deposition. They are known for a high tunability of their structural properties, e.g. thickness and roughness on nanoscale. The interplay of internal interactions and structure of PEM is investigated by means of swelling experiments, i.e. an internal mechanical stress in the films is induced by incorporation of solvent molecules from adjacent solvent vapour (H2O). Neutron reflectometry is used to test for structure parameters of the sample and its specific material content of polymer and solvent. Three different PEM systems made from PSS/PDADMAC* by spraying technique are investigated; each containing a derivative of the polycation PDADMAC of 75, 89, or 100% charge density (ChD) along the molecular chain, also the number of adsorbed layers of polyions, i.e. the film thickness, is varied. The swelling characteristics changes continuously and systematically with the number of adsorbed bilayers indicating internal transitions of structure and swelling. Lower ChD results in thicker films. * poly-(styrene sulphonate)/ poly-(diallyldimethyl ammonium)