ABSTRACT
This chapter describes experiments to characterize the viscoelastic behavior of wormlike micelle solutions. It summarizes the rheological performances of different surfactant systems. The chapter suggests that elasticity is a universal feature shared by almost all surfactant systems, while relaxation dynamics is very system specific. Aqueous solutions of surfactants often present pronounced viscoelastic properties because amphiphilic molecules in water form micelles of different shapes and possibly ordered. They belong to the family of complex fluids that have attracted the attention of physical chemists. Recognition of the analogy between wormlike micelles and polymers shed much light in the understanding of the rheological behavior. Models originally developed to describe the rheological properties of polymers were adapted to wormlike micelle solutions. Viscoelasticity of surfactant solutions is related to the growth of cylindrical wormlike micelles. Therefore all factors governing the packing parameter are to be considered to account for the viscoelastic behavior. Wormlike micelles are obtained with all kinds of surfactants.
