Berlin 2024 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 4: Interfaces and Thin Films
CPP 4.1: Vortrag
Montag, 18. März 2024, 09:30–09:45, H 0111
Structure and dynamics in functional polymer hydrogel films — •Lucas Kreuzer1, Calvin Brett2, Jacques Ollivier3, Stephan Roth2, André Laschewsky4, Christine M. Papadakis5, and Peter Müller-Buschbaum5 — 1Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) — 2Deutsches Elektronen Synchrotron (DESY) — 3Institut Laue-Langevin (ILL) — 4Universität Potsdam, Institut für Chemie — 5TUM School of Natural Sciences, Technische Universität München
Hydrogel films made from responsive polymers are able to switch between a swollen and a contracted film state in response to slight changes in their surroundings. This behavior can be used to generate highly functional hydrogel thin films e.g., from a multi-responsive diblock copolymer model system containing a zwitterionic poly(sulfobetaine) and a nonionic poly(N-isopropyl acrylamide) block. With neutron scattering techniques, we identified discrete thin-film states, regarding their thickness and film morphology, which can be precisely tuned upon changing external stimuli such as temperature or the composition of the surrounding solvent vapor. Using this knowledge, we now focus on a nanocomposite film from cellulose nanofibrils (CNF) and the electrically conductive polymer poly(3,4-ethylenedioxythiophene):poly styrene sulfonate (PEDOT:PSS). Upon cyclic swelling and drying processes, we investigated the film morphology and internal dynamics. Moreover, the influence of temperature was studied. A first analysis already indicates a correlation between the structural properties, dynamics of water inside the film, and electrical conductivity.
Keywords: functional materials; responsive materials; cellulose; neutron scattering; thin film