Definition. The DLVO theory is named after Derjaguin, Landau, Verwey, and Overbeek. It is the explanation of the stability of colloidal suspension. It describes the balance between two forces, electrostatic repulsion and van der Waals attraction. Implications of the DLVO theory for problems associated with colloid particle adsorption and deposition at solidrliquid interfaces were reviewed. The electrostatic. DLVO theory. [email protected] Poly. Loading Unsubscribe from [email protected] Poly? Cancel Unsubscribe.
|Published:||17 October 2015|
|PDF File Size:||1.54 Mb|
|ePub File Size:||13.82 Mb|
Otherwise, particles will aggregate due to the attraction potential.
DLVO theory - Wikipedia
Since particles have to overcome this barrier in order to aggregate, two particles on a collision dlvo theory must have sufficient kinetic energy due to their velocity and mass. This inner region is often referred to as an energy trap since the colloids can be considered to be trapped together by Van der Waals dlvo theory.
At primary minimum, attractive forces overpower the repulsive forces at low molecular distances.
For pure oils in water there is a surprisingly large charge created, so it is said, by OH- ions dlvo theory prefer to be at the surface. The charge distribution is hugely complicated and is measured experimentally as a Zeta potential, which is described in detail on the Zeta Potential page.
The rule of thumb is that any Zeta potential less than, say, 30mV absolute value is unlikely to give sufficient stability. Ionic surfactants obviously provide significant surface charge - dlvo theory they've had a chance to reach the interface.
The effect of the surface dlvo theory is diluted if salt is present in the formulation. The curve which represents an attractive energy indicates the variation in van der Waals force between colloidal particles.
The DLVO theory dlvo theory the tendency of colloids to agglomerate or separate by combining two curves of electrostatic repulsion and van der Waals attraction.
At each distance, the smaller value is subtracted from the larger value to obtain the net energy.
- DLVO | Practical Surfactants Science | Prof Steven Abbott
- DLVO theory - Soft-Matter
- The DLVO Theory
- Please note:
In the regime where there is repulsion, energy can be thought to be a energy barrier. This integration is facilitated dlvo theory assuming the second sphere's presence does not disrupt the first sphere's ion cloud.
The resulting superposition approximation yields a screened Coulomb repulsion for the effective inter-sphere interaction, 9 The full DLVO potential includes a term accounting for dispersion interactions. These are negligibly weak for well-separated spheres [ 19dlvo theory ], however, and are omitted from.