Other Types of Smart Wormlike Micelles

Abstract

In comparison with the widely reported triggers described in previous chapters-namely temperature, pH, and light-this chapter discusses triggers which have been far less documented: redox potential and hydrocarbons and their use to control the assembly and properties of wormlike micelles. In addition, recent reports of multiple stimuli-responsive wormlike micelles are also described, as well as smart reverse wormlike micelles, to complete this collection of "unconventional" smart wormlike micelles.Keywords Redox-responsive · Hydrocarbon-responsive · Multi-responsive · Smart reverse wormlike micelles Redox-Responsive WLMsThe first redox-sensitive surfactant was reported nearly 30 years ago by Saji et al. [1,2]. They incorporated a ferrocene-based moiety into the surfactant and found that the CMC and micellization behaviour were altered under the stimulus of electron transfer, and they observed that micelles could be broken up into monomers by oxidation and re-formed by reduction. More details on this type of surfactants can be found in recent reviews by Abbott [3] and Eastoe [4].Despite this prior work, the only example of redox-sensitive WLMs, to our knowledge, was reported by Abe et al. [5] in 2004, and motivated by the development of electro-rheological (ER) fluids. ER fluids are colloidal dispersions whose viscosity can be controlled by an applied electric potential and are regarded as versatile materials for building up smart structures and machines. These fluids have applications in valves and clutches for transmission and precise control of mechanical positioning. They are conventionally produced by dispersing solid particles within a liquid. The application of an alternating electric field to the ER dispersions produces a viscosity increase mainly in the direction perpendicular to the field, because the dispersed particles align to form strings in the direction parallel

The Formation of pH-Sensitive Wormlike Micelles in Ionic Liquids Driven by the Binding Ability of Anthranilic Acid

“…Molecular self-assembly is a kind of entity with a special structure, which associates spontaneously by molecules [ 1 , 2 , 3 , 4 , 5 , 6 ]. It not only promotes the development of functional and complex materials, but also leads to the formation of different aggregate morphologies such as crystalline structures, wormlike micelles, vesicles, and spherical micelles [ 7 , 8 , 9 ]. Among them, wormlike micelles (WLMs) have drawn much attention from researchers all over the world because of their outstanding performance and extensive applications [ 10 , 11 , 12 , 13 ].…”