Surface forces and friction between non-polar surfaces coated by temperature-responsive methylcellulose
2014 (English)In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, Vol. 441, 701-708 p.Article in journal (Refereed) Published
Methylcellulose is a heterogeneous polymer that exposes both methyl groups and -OH-groups to the solution, and the solvent quality of water for methylcellulose deceases with increasing temperature. In bulk solution this leads to aggregation into fibrils at high temperatures. In this report we address how temperature affects adsorbed layers of methylcellulose on hydrophobized silica surfaces in contact with an aqueous methylcellulose solution. The layers were imaged using PeakForce tapping mode atomic force microscopy, in order to determine how the additional adsorption that occurs with increasing temperature affects the layer structure. Surface force and friction measurements were carried out using the AFM colloidal probe method. The data demonstrate that the normal surface forces were rather insensitive to temperature, whereas the friction forces changed significantly with increasing temperature. At low loads the friction increases with increasing temperature, whereas at high loads the reverse is observed. These findings are discussed in terms of how the worsening of the solvent condition affects the aggregation state in the adsorbed layer, and the polymer-surface affinity.
Place, publisher, year, edition, pages
2014. Vol. 441, 701-708 p.
Temperature-responsive polymer, Cellulose ethers, Methylcellulose friction, Load bearing capacity, Atomic force microscopy, Surface forces
IdentifiersURN: urn:nbn:se:kth:diva-95377DOI: 10.1016/j.colsurfa.2013.10.038ISI: 000329260800090ScopusID: 2-s2.0-84887548022OAI: oai:DiVA.org:kth-95377DiVA: diva2:527990
FunderVinnovaSwedish Foundation for Strategic Research
QC 20140131. Updated from manuscript to article in journal.2012-05-232012-05-232014-01-31Bibliographically approved