| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 594503 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2011 | 7 Pages |
The rheology of highly concentrated emulsions stabilized with bovine serum albumin and the same protein with the addition of two different cationic surfactants was studied. These materials demonstrate non-Newtonian behavior with zero-shear-rate Newtonian viscosity and rather abrupt decrease of viscosity in a narrow shear stress range. Emulsions also possess elastic properties and storage modulus does not depend on frequency. The addition of low-molecular-mass surfactant leads to the modification of all rheological properties: the viscosity, storage modulus, and yield stress decrease. Variation of the added surfactant in a very wide range shows that there is its threshold concentration, at which a surfactant substitutes protein in the interfacial layers. It was supposed that some peculiarities of emulsions under study are explained by their wide size distribution. As a result, these emulsions are possibly not “compressed” and their elasticity is mainly due to interlayer interactions rather than interfacial tension.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We examine visco-elasticity of highly concentrated emulsions stabilized with bovine serum albumin. ► Materials demonstrate non-Newtonian behavior. ► Additions cationic surfactants lead to decrease of viscosity, storage modulus and yield stress. ► There is its threshold concentration at which elasticity and yield stress tend to disappear. ► At high concentrations surfactant substitute protein in the interfacial layers.
