Surface forces between highly charged cationic polyelectrolytes adsorbed to silica: How control of pH and the adsorbed amount determines the net surface charge

Junhao Huang, Xiaoyan Liu, Esben Thormann*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

230 Downloads (Pure)

Abstract

Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation (QCM-D) were employed to investigate the pH dependent adsorption of poly(diallyl dimethyl ammonium chloride) (polyDADMAC) to silica surfaces as well as the surface forces between these layers. It was found that polyDADMAC adopted a relatively flat conformation when adsorbed to a silica surface, and that the adsorbed amount increased with increasing pH. From the surface force measurements it is evident that the surface undergoes a charge reversal upon saturation with polyDADMAC, at the three different investigated pH values and that some degree of charge regulation of the silica surface takes place during the adsorption process. Finally, the overcharging phenomenon is discussed in terms of a geometrical mismatch due to the different average spacing between the surface charges on the silica surface and the size of the polyDADMAC monomer.
Original languageEnglish
JournalLangmuir
Volume34
Issue number25
Pages (from-to)7264-7271
Number of pages8
ISSN0743-7463
DOIs
Publication statusPublished - 2018

Fingerprint Dive into the research topics of 'Surface forces between highly charged cationic polyelectrolytes adsorbed to silica: How control of pH and the adsorbed amount determines the net surface charge'. Together they form a unique fingerprint.

Cite this