Polyelectrolyte lubrication measured by colloidal probe AFM
2010 (English)In: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIET: volume 239, 2010, COLL-91- p.Conference paper (Refereed)
AFM-colloidal probe was used to measure surface interactions and friction forces between polyelectrolyte coated surfaces. We used highly charged polyelectrolyte together with oppositely charged surfactant; that associate in bulk solution and form complexes. Even at the surface, similarly structured polyelectrolyte-surfactant layers were spontaneously formed and the lubrication properties of these layers were highly interesting: having a high load bearing capacity, and very low friction coefficient. Interestingly, when the applied load was increased stepwise the friction force as a function of load displays some sharp peaks, due to structural rearrangements in the polyelectrolyte-surfactant layer. On unloading very low frictional forces was obtained despite the presence of adhesion between the layers. It is shown that in order to maintain favorable lubricating properties it is essential to have the surfactant present in solution, whereas, after the initial polyelectrolyte adsorption step, there is no need to have the polyelectrolyte present in the bulk.
Place, publisher, year, edition, pages
2010. COLL-91- p.
IdentifiersURN: urn:nbn:se:kth:diva-84393OAI: oai:DiVA.org:kth-84393DiVA: diva2:499321
239st National Meeting and Exposition of the American-Chemical-Society (ACS), San Francisco, CA, MAR 21-25
QC 201204182012-02-132012-02-132012-04-18Bibliographically approved