Rehbinders Lyophilic Structural-Mechanical Barrier as a Factor of Strong Colloid Stability

2 REHBINDER S LYOPHILIC STRUCTURAL-MECHANICAL BARRIER AS A FACTOR OF STRONG COLLOID STABILITY 

The original teachings of Rehbinder and his school on colloid stability were based on some qualitative concepts that were known with regard to protective colloids. As one of the factors of colloid stability, Rehbinder s teachings included the concept of the so-called steric stabilization, which was fully developed at a later time. The principal achievements and contribution of Rehbinder and 

FIGURE 4.10 Schematic illustration of Rehbinder s structural-mechanical barrier as a strong factor of colloid stability. 

Appealing to concepts regarding thermodynamic and nonthermodynamic stabilization factors, we can state that strong stabilization against both high electrolyte concentration and high concentration of the disperse phase is due to the mechanical resistance of film to rupture and resistance to a displacement from the gap between droplets, bubbles, and particles. In the case of solid particles, this can be achieved by the firm affachment of the adsorption layer to the surface (i.e., by chemisorption), whereas in the case of emulsions (mobile fluid-fluid interface), it is necessary for the interface itself to have sufficient mechanical stability. The latter include high (nonlinear) viscosity. 

Physical-Chemical Mechanics of Disperse Systems and Materials 

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