Properties of Cationic Polyelectrolyte Layers Adsorbed on Silica and Cellulose Surfaces Studied by QCM-D—Effect of Polyelectrolyte Charge Density and Molecular Weight

Abstract

The adsorption of cationic polyelectrolytes (C-PAMs and PDACMAC) with different charge densities and molecular weights on silica and cellulose model surfaces was examined using a quartz crystal microbalance with dissipation, QCM-D. The conformation and viscoelastic properties of the adsorbed polyelectrolyte layers were studied by modelling the data with the Q-Tools program. When comparing the adsorption behavior on cellulose and silica a clear difference both in adsorption kinetics of polyelectrolytes and the viscoelastic properties of the formed polyelectrolyte film was observed. On cellulose the polyelectrolyte films were viscous and more dissipative at the beginning of the adsorption but when the adsorption proceeded the layers became more rigid and stiffer, in contrast to the behavior on silica.

Keywords:

• Cellulose
• polyelectrolyte adsorption
• QCM-D
• silica
• viscoelastic properties

This work was funded by Tekes (Finnish Funding Agency for Technology and Innovation), Kemira Oyj, M-Real Oyj, Stora Enso Oyj and UPM-Kymmene. The authors would like to thank Tekla Tammelin, Dr. Tech., and Jani Salmi, M.Sc, for valuable discussions, technicians Ms. Marja Kärkkäinen and Ms. Ritva Kivelä for their excellent assistance with the laboratory work and Kemira Oyj for providing the polyelectrolytes.

Notes

Part of the special issue, Surface and Colloid Chemistry Without Borders: An International Festschrift for Professor Per Stenius on the Occasion of His 70th Birthday.