An exciting challenge for soft matter chemists is the development of smart materials that can respond to “triggers” from their environment. By using materials which form by supramolecular self assembly, researchers can use very simple building blocks to create sophisticated materials, which can be applied in key areas such as diagnostics, biosensors, drug delivery, tissue engineering and smart optical systems.
This Chem Soc Rev review by Zonglin Chu, Cécile Dreiss and Yujun Feng describes the potential and application of stimuli-responsive “wormlike micelles” (WLMs). These are long, flexible structures assembled from molecules that contain both hydrophilic and hydrophobic areas, and so assemble into a wide range of micellar structures in an aqueous environment. Under certain conditions, these structures are constantly breaking and reforming, and are referred to as “living.” Small changes in the environment can offset this balance and cause large changes to the properties of the material.
One fascinating example reviewed by Chu, et al. is the thermo-responsive gel system reported by Huang and co-workers in 2009 (see figure below). At 21 °C, this system is a transparent fluid, but cooling it to 20 °C results in the formation of a gel. This is a drastic, reversible change in response to a small modification of the environment.
Figure taken from Y. Lin et al., Soft Matter, 2009, 5, 3047-3053.
This Review provides an in-depth coverage of recent advances in the development of interesting wormlike micelle systems, including systems which can be switched “on” and “off” by electrical, optical, thermal and pH triggers, and an excellent understanding of WLM behaviour and their practical applications.
Read this Chemical Society Reviews article today:
Smart wormlike micelles
Zonglin Chu, Cécile A. Dreiss and Yujun Feng
Chem. Soc. Rev., 2013, Advance Article
DOI: 10.1039/C3Cs35490C
Cally Haynes is a guest web-writer for Chem Soc Rev. She is currently a post doctoral researcher at the University of Southampton, and her research interests include the supramolecular chemistry of anions. When not in the laboratory, she likes travelling and watching football.
