uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Novel evaluation method of neutron reflectivity data applied to stimulus-responsive polymer brushes
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics III.
Show others and affiliations
2008 (English)In: Soft Matter, ISSN 1744-683X, Vol. 4, no 3, 500-509 p.Article in journal (Refereed) Published
Abstract [en]

Neutron reflectivity (NR) measurements have been performed on stimulus-responsive polymer brushes containing N-isopropylacrylamide (NIPAAM) at different temperatures and contrasts using two different brush samples of roughly the same grafting density and layer thickness. The NR data were analyzed using a novel method employing polymer density profiles predicted from lattice mean-field theory augmented with a polymer model to describe polymer solubility that decreases with increasing temperature. The predicted density profiles at the different temperatures were self-consistent with the experimentally observed profiles; hence the experimental data lend credibility to the theory. We found that the brush thickness decreased from 220 to 160 nm and the polymer volume fraction increased from 55 to 75% when increasing temperature from 293 to 328 K. The new evaluation approach involved significantly fewer independent fitting parameters than methods involving layers of uniform densities. Furthermore, the approach can straightforwardly be extended to analyze neutron reflectivity data of grafted, weakly charged polymers that display pH-sensitive behaviour and also to block copolymers and to surfaces with adsorbed polymers. We propose that such accurate model calculations provide a tool to interpret results from NR experiments more effectively and design neutron reflectivity experiments for optimal outcome.

Place, publisher, year, edition, pages
2008. Vol. 4, no 3, 500-509 p.
National Category
Physical Sciences
URN: urn:nbn:se:uu:diva-14588DOI: 10.1039/b714911eISI: 000253492400016OAI: oai:DiVA.org:uu-14588DiVA: diva2:42359
Available from: 2008-01-31 Created: 2008-01-31 Last updated: 2010-01-12Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Rennie, Adrian
By organisation
Physics III
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 179 hits
ReferencesLink to record
Permanent link

Direct link