Surface properties of hydrophobically modified carboxymethylcellulose derivatives. Effect of salt and proteins

The interfacial behavior of carboxymethylcellulose (CMC) and of hydrophobically modified CMCs has been assessed using surface tension and surface pressure measurements. The results showed that surface properties of these polymers are related to both the nature of the hydrophobic chain grafted to the polymer and the ionic strength. The observed differences in adsorption kinetics between the studied hydrophobized CMCs appeared to be controlled by packings of polymer aggregates formed in the subphase and were due to the nature of grafted hydrophobic chains. The observed uptake of proteins by CMC has been attributed to electrostatic interactions between the charged proteins (beta-lactoglobulin, ovalbumin and thyroglobulin) and the polyanion. This uptake was enhanced for hydrophobically modified CMCs and for the proteins with increased molecular weights. (C) 2000 Elsevier Science B.V. All rights reserved.