Regensburg 2019 – wissenschaftliches Programm
CPP 11.1: Vortrag
Montag, 1. April 2019, 15:00–15:15, H8
GISANS sample environment for the investigation of thin polymer films — •Tobias Widmann1, Lucas Kreuzer1, Nuri Hohn1, Kun Wang1, Gaetano Mangiapia2, Yvonne Hertle3, Thomas Hellweg3, and Peter Müller-Buschbaum1 — 1TU München, Physik-Department, LS Funktionelle Materialien, 85748 Garching — 2HZG at MLZ, 85748 Garching — 3Bielefeld University, Physical and Biophysical Chemistry, 33615 Bielefeld
The investigation of thin polymer films with neutrons allows a non-destructive probe on their structure and composition. In the framework of the FlexiProb project, which plans an interchangeable sample environment for different neutron experiments at the European spallation source (ESS), we designed a setup for grazing incidence small angle neutron scattering (GISANS). The new sample chamber offers a wide range of adjustable relative humidity with fast switching times. Moreover, a homogeneous heat distribution and reduced condensation of the humid air is realized by a spherical design with fluidic channels inside the chamber walls. A separate gas-mixing and air-flow setup, gives precise control over the air conditions inside the chamber. To demonstrate its options, thin microgel films constituted of thermoresponsive NIPAM with N,N'-methylenebisacrylamide as cross-linkers are placed inside and humidified from 0 to 100 %RH and vice versa. The film response is analyzed with time-of-flight GISANS in order to observe structural changes in the films over the course of the humidification.