Parts | Days | Selection | Search | Updates | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 25: Interfaces and Thin Films II
CPP 25.4: Talk
Tuesday, March 13, 2018, 10:30–10:45, PC 203
Near surface dynamics of PEG and PNIPAM based polymer brushes — •Judith Witte1, Tetyana Kyrey1,2, Regine von Klitzing3, Olaf Holderer2, and Stefan Wellert1 — 1TU Berlin, Institute for Chemistry, Berlin, Germany — 2Heinz Maier Leibniz Zentrum, JCNS, Garching, Germany — 3TU Darmstadt, Institute for Condensed Matter Physics, Darmstadt, Germany
The physical properties of stimuli-responsive polymer brushes still receive vast interest in basic research. Polymer brushes undergoing a temperature induced phase transition are of major interest for technical applications such as (bio)functional coatings. Polymer brushes are polymers end-tethered to a solid surface. A variation of the chemical composition, brush height or grafting density allows for a wide range of different polymer coatings with distinct properties. Among them, thermoresponsive polymer brushes based on P(MEO2MA-co-OEGMA) are, due to their biocompatibility, promising candidates for smart biocoatings. PNIPAM based polymer brushes serve as a prominent model system for thermoresponsive polymer coatings. Here we focus on recent grazing incidence neutron spin echo spectroscopy experiments probing the dynamics inside these polymer brush layers on the nanometer length and nanosecond time scale. At two neutron penetration depths we explored the segmental dynamics well below the LCST. The data suggest an influence of the nonuniform blob size on the relaxation time inside the brushes which is discussed in the talk.