Interactions between Bottle-Brush Polyelectrolyte Layers: Effects of Ionic Strength and Oppositely Charged Surfactant
2008 (English)In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 323, no 1, 191-202 p.Article in journal (Refereed) Published
Interactions between cationic bottle-brush polyelectrolyte layers adsorbed on mica across salt and oppositely charged surfactant solutions were investigated with the interferometric surface force apparatus, and the results were compared with what is known for similarly charged linear polyelectrolytes. Ellipsometric measurements demonstrated that the bottle-brush polyelectrolytes, which contain 45 units long poly(ethylene oxide) side chains, are more readily desorbed than linear equivalents when the ionic strength of the solution is increased. It is argued that this is due to the steric repulsion between the poly(ethylene oxide) side chains that reduces the surface affinity. The preadsorbed bottle-brush polyelectrolyte layers were also exposed to sodium dodecyl sulfate (SDS) solutions. It was found that the presence of SDS affected the force profiles less than observed for similarly charged linear polyelectrolytes. This observation was attributed to excluded volume constraints imposed by the poly(ethylene oxide) side chains that reduces the accessibility of the charged polyelectrolyte segments and counteracts formation of large aggregates within the layer.
Place, publisher, year, edition, pages
2008. Vol. 323, no 1, 191-202 p.
polyelectrolyte, brush polyelectrolyte, bottle-brush polyelectrolyte, comb polyelectrolyte, poly(ethylene oxide), surfactant, association, surface force apparatus (SFA), phase modulated ellipsometry, mica, sodium dodecyl sulfate
IdentifiersURN: urn:nbn:se:kth:diva-8155DOI: 10.1016/j.jcis.2008.02.071ISI: 000256646600027ScopusID: 2-s2.0-44149114718OAI: oai:DiVA.org:kth-8155DiVA: diva2:13403
QC 201008302008-03-272008-03-272010-08-30Bibliographically approved