Deducing the Relation between Viscosity and Oil-Induced Structural Changes of Viscoelastic Surfactants Using a
Lionel T Fogang1, Theis I Solling1, Jan S Pedersen2
1Center for Integrative Petroleum Research, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia.
Abstract:
The present study relates viscosity reduction with time of a wormlike micellar solution to the micellar transitions that occur with time in the presence of three n-alkanes, namely, n-decane, n-dodecane, and n-hexadecane. Steady-shear rheology and small-angle X-ray scattering were used to deduce the relationship. The effect of n-alkane concentration was tested only with n-decane. There were at most three stages of viscosity reduction, which appeared in the following order: (i) the rising viscosity stage, (ii) the fast viscosity reduction stage, and (iii) the low-viscosity stage. The stages and rates of viscosity transition depended on the type of micelles present and the degree of micelle entanglement. Moreover, the rate of transition increased when the n-alkane concentration was increased and when the n-alkane molecular mass was reduced. n-Hexadecane induced only the first two stages of transition at a slower rate compared to the other oils.
Related Concept Videos
Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Viscosity of Fluid
Viscosity
The SI unit of viscosity is...
Newtonian Fluid: Problem Solving
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Stokes' Law
The expression for the force on a solid spherical object in a fluid is called Stokes' law. Stokes' law is valid only...
Factors Affecting Dissolution: Particle Size and Effective Surface Area


