Grazing incidence neutron spin echo study of poly(N-isopropylacrylamide) brushes

Witte, J., Krause, P., Kyrey, T., Dahl, A. M., Lutzki, J., Schmidt, B. V. K. J. , Ganeva, M., Koutsioubas, A., Holderer, O. and Wellert, S. (2020) Grazing incidence neutron spin echo study of poly(N-isopropylacrylamide) brushes. Macromolecules, 53(5), pp. 1819-1830. (doi: 10.1021/acs.macromol.9b01247)

Abstract

The structure and dynamic properties of poly(N-isopropylacrylamide) brushes at solid planar surfaces under good solvent conditions are studied. Polymer brushes with grafting densities in the concentrated and semidilute regime are prepared via surface-initiated atom transfer radical polymerization. The polymer brushes were removed from the substrates to determine the molar mass and molecular dispersity via size-exclusion chromatography to draw conclusions about the grafting density. The structure of the brushes was investigated with ellipsometry and neutron reflectometry measurements. We found an influence of the grafting density on the swelling properties of the poly(N-isopropylacrylamide) brushes. Furthermore, the brush dynamics at different neutron penetration depths was analyzed with neutron spin echo spectroscopy under grazing incidence. The evanescent intensity distribution was modeled with the BornAgain software package, which uses the distorted-wave Born approximation.

• Item Type: Articles
• Additional Information: The authors thank Deutsche Forschungsgemeinschaft DFG for funding (grant number WE5066/3-1 (S.W.) and HO5488/2-1 (O.H.)).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Schmidt, Dr Bernhard
• Authors: Witte, J., Krause, P., Kyrey, T., Dahl, A. M., Lutzki, J., Schmidt, B. V. K. J., Ganeva, M., Koutsioubas, A., Holderer, O., and Wellert, S.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Macromolecules
• Publisher: American Chemical Society
• ISSN: 0024-9297
• Published Online: 19 February 2020
• Copyright Holders: Copyright © 2020 American Chemical Society
• First Published: First published in Macromolecules 53(5): 1819-1830
• Publisher Policy: Reproduced in accordance with the publisher copyright policy