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S. M. Levachev, A. E. Harlov, A. N. Kukuchkina, N. V. Novosyolova, V. N. Matveenko, S. R. Derkatch
Rheological behavior of
concentrated emulsions stabilized by bovine serum albumin and Tween 80
Abstract
Rheological behavior of
concentrated emulsions toluene-in-water containing globular protein bovine
serum albumin (BSA) and nonionic surfactant Tween 80 has been investigated at
temperature 22oC. Concentration of disperse phase was 74 - 83 %. Influence nonionic
surfactant which concentration varied in a wide range up to KKM and above KKM has been studied. It is shown, that
emulsions under shear deformation behave as nonNewtonian liquids and are
characterized by yield stress, at low shear rates on flow curves there is an
area of the greatest Newtonian viscosity which decreases at increase in
concentration of Twin 80. With increase in content of Twin 80 yield stress goes
down in comparison with emulsions, stabilized by BSA without surfactant. The
results are explained by changing composition of interphase adsorption layers
formed on the surface of drops – replacement of protein by low-molecular-mass
surfactant during competitive adsorption.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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