Berlin 2012 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 13: Poster: Interfaces and Thin Films

CPP 13.24: Poster

Tuesday, March 27, 2012, 18:15–20:45, Poster A

Swelling of Polyelectrolyte Multilayers in Ionic Liquid — Nagma Parveen^1,2 and •Monika Schönhoff¹ — ¹Institute of Physical Chemistry, University of Muenster, Corrensstr. 28/30, D-48149 Muenster, Germany — ²NRW Graduate School of Chemistry, University of Muenster, Wilhelm-Klemm-Str. 10, D-48149 Muenster, Germany

Their controlled thickness and high mechanical stability make Polyelectrolyte Multilayers (PEM) promising ion conducting membranes. Suitable electrolyte solvents could possibly enhance the ionic conductivity for application in Li batteries. Here, the swelling of PEM with Ionic Liquid (IL) is investigated by Quartz Crystal Microbalance (QCM-D). PEM films are prepared with different combinations of polyelectrolyte, employing PSS/PAH, and PSS/PDADMAC. 1-Hexyl-3-methyimidazolium chloride is used here as a room temperature ionic liquid (RTIL). An enhancement of mass coverage and dissipation is found for films in contact with solutions of IL, suggesting incorporation of IL into the films, accompanied by film swelling. The swelling increases linearly with IL concentration. It is reversible at low IL concentrations, while at higher concentrations irreversible film decomposition occurs. The incorporation can be attributed rather to hydrophobic than to ionic interactions, since PDADMAC-containing films swell more strongly. Generally, the overall swelling can be decomposed into a fast and a slow process of IL uptake and chain reorganisation, respectively. Reversibility and stablility limits of PEM in IL solutions are established by these data.