1. Introduction
It is well known that micelles in aqueous solutions of surfactants
grow one-dimensionally by tuning surfactant hydrophobically, and
long, flexible aggregates called wormlike micelles are produced. If
the scission energy, which is the energy required to break a wormlike
micelle into smaller parts, is large enough, the length of the rods
can become longer than their persistence length, and the micelles
behave like semi-flexible linear polymer chains. Because of entanglement
of the wormlike micelles, the wormlike micellar solutions
show highly viscoelastic properties. Wormlike micelles are different
from polymers because they can break and reform under shear
forces as the wormlike micelles are composed of low-molecularweight
molecules.
In order to grow a spherical micelle into a wormlike micelle,
the effective head group area of surfactants must be decreased,
for example, by adding salts that screen the electrostatic repulsions
between the neighboring head groups. Wormlike micelles
have been shown to form in some ionic surfactant systems, by