Rheology of Wormlike Micelles: Equilibrium Properties and Shear Banding Transitions

Abstract

We review the experimental and theoretical results obtained during the past decade on the structure and rheology of wormlike micellar solutions. We focus on the linear and nonlinear viscoelasticity and emphasize the analogies with polymers. Based on a comprehensive survey of surfactant systems, the present study shows the existence of standard rheological behaviors for semidilute and concentrated solutions. One feature of this behavior is a shear banding transition associated with a stress plateau in the nonlinear mechanical response. For concentrated solutions, we show that in the plateau region the shear bands are isotropic and nematic.

A systematic rheological study of alkyl amine surfactants for fluid mobility control in hydrocarbon reservoirs

“…Similar temperature effects are reported for other aminebased surfactants where wormlike micelles can spontaneously form at ambient temperatures based on the addition of salts, counterions, cosurfactants, surfactant mixtures, block copolymers, and/or organic solvents to the solution (Berret 2006;Hu and Lips 2005;Li et al 2011;Rabie and Nasr-El-Din 2015;Shashkina et al 2005;Wang et al 2012). In particular, as temperature increases, the viscosity initially rises to an inflection point then begins degrading afterward and this process can repeat at higher temperatures (Rabie and Nasr-El-Din 2015).…”

“…Furthermore, a slight degree of shear thickening occurs at lower salt concentrations and/or dilute solutions, leading to a fractional viscosity increase of 0.2 mPa s from 1 to 100 s -1 . This can indicate hydrodynamic instabilities above a critical shear rate in the solution, most likely attributed to the formation of nonequilibrium, shear-induced, micellar phase transitions (Barentin and Liu 2001;Berret 2006;Hu et al 1998). In addition, shear thickening under steady shear can occur when the surfactant concentration is close to the critical micelle concentration (Koehler et al 2000).…”

“…The presence of hydrophobic terminals, such as methyl groups found in DTTM and ARM, can dehydrate the surfactant molecules with excess salt in the aqueous solution. This hydrophobicity favors the growth of long micelles, since hydrophobic molecules have higher end-cap energies, and end-cap energy is exponentially proportional to the micellar length (Berret 2006;Raghavan and Kaler 2001;Raghavan et al 2002). End-cap energy represents the excess packing energy for surfactants with preferential cylindrical aggregation and is defined as the energy required to create two new chain ends for neutral micelles (Berret 2006).…”

“…This hydrophobicity favors the growth of long micelles, since hydrophobic molecules have higher end-cap energies, and end-cap energy is exponentially proportional to the micellar length (Berret 2006;Raghavan and Kaler 2001;Raghavan et al 2002). End-cap energy represents the excess packing energy for surfactants with preferential cylindrical aggregation and is defined as the energy required to create two new chain ends for neutral micelles (Berret 2006). Large end-cap energy drives the transformation of cylindrical micelles to long and entangled wormlike or branched micelles, while low end-cap energy is achieved by forming closed loops or rings (Zana and Kaler 2007).…”

The Elasticity of Soap Bubbles Containing Wormlike Micelles

“…15,16 Two excellent reviews on WLM can be found in the literature. 17,18 In the CTAB/salicylate system, WLM are formed for ξ > 0. 6,19 which is the same for the saturation of the surface with salicylate ions, as observed in SFG experiments.…”