Formation of hydrated layers in PMMA thin films in aqueous solution
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Date
2015-10-30
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Abstract
Neutron reflectometry (NR) measurements have been made on thin (70–150 Å) poly(methylmethacrylate) (PMMA) films on Si/SiOx substrates in aqueous conditions, and compared with parameters measured using ellipsometry and X-Ray reflectometry (XRR) on dry films. All techniques show that the thin films prepared using spin-coating techniques were uniform and had low roughness at both the silicon and subphase interfaces, and similar surface energetics to thicker PMMA films. In aqueous solution, NR measurements at 25 °C showed that PMMA forms a partially hydrated layer at the SiOx interface 10 Å under the film, while the bulk film remains intact and contains around 4% water. Both the PMMA film layer and the sublayer showed minimal swelling over a period of 24 h. At 50 °C, PMMA films in aqueous solution roughen and swell, without loss of PMMA material at the surface. After cooling back to 25 °C, swelling and roughening increases further, with loss of material from the PMMA layer. © 2017 Elsevier B.V.
Description
Keywords
Protective coatings, Neutron reflectors, Hydration, Thin films, Hydrophylic polymers, Aqueous solutions
Citation
Akers, P. W., Nelson, A. R. J., Williams, D. E., & McGillivray, D. J. (2015). Formation of hydrated layers in PMMA thin films in aqueous solution. Applied Surface Science, 353, 829-834. doi:10.1016/j.apsusc.2015.06.199