The Colloidal Domain – where physics, chemistry, biology and technology meet

The book “The colloidal Domain“ by Evans and Wennerström is now available in the second edition. The book provides a well written and clear description of the state-of-the art in colloid science. The major emphasis is given to surfactant based systems but two chapters on polymers and colloidal sols are included. Apparently the book originates from the authors’ lecture manuscripts and thus the different topics are presented in a manner that demonstrates how the various approaches on different levels must be combined to understand colloidal systems. The main scientific chapters of the books are sort of framed by the introduction and an Epilogue. The former gives some historic remarks and outlines the general relevance of colloidal systems. The Epilogue, which has been added to the 2 edition, reviews the concepts discussed in the book and again summarizes how different aspects come together for the leitmotif “colloidal domain“. The book starts with a chapter on selfassembly of amphiphiles in solution and the thermodynamics involved in micelle formation are presented. The general characteristics of the selforganization are introduced and the importance of the chemical potential for the thermodynamic description of micellization is outlined. The second chapter covers properties of surfaces and monolayers. The concept of surface tension and its thermodynamic basis are discussed and Gibbs and Langmuir isotherms are introduced. Different experimental techniques including standard surface tension measurements as well as fluorescence and force microscopy are explained. Electrostatic interactions are the topic of the third chapter, which has been reorganized and extended compared to the first edition. Starting from interactions between molecules in the gas phase, the Poisson-Boltzmann equation and the DebyeHückel theory are derived. The thermodynamics and electrostatics derived in the previous chapters are then used to explain structure and properties of micelles, e.g. differences between ionic and nonionic micelles. The fourth chapter ends with a discussion of solubilization and the digestion of fat is used as one example. It follows a chapter on colloidal forces that of course leads to the DLVO-Theory. However, the authors include a discussion of the effect of ion correlations as well as molecular packing forces. This chapter further includes a discussion of the hydrophobic interaction, again a part that was added in the 2 edition. Chapter 7 focuses on bilayer systems mainly those formed by biological lipids. First, different bilayer structures as, e.g. liquid crystalline, gel or bicontinuous phases and vesicles are introduced together with a description of the surfactant chemist‘s “toolbox“ (x-ray scattering, microscopy, NMR, DSC, surface focus apparatus) which is necessary to characterize these structures . This chapter also covers the role of bilayers as barriers. The following three chapters discuss polymers, colloidal sols and colloidal stability and provide the basic concepts important in these complex fluids. The polymer chapter also includes some pages on rheology but of course flow properties could not be a main topic in this book. The general phase behavior of binary and ternary surfactant containing mixtures and properties of emulsions, microemulsions and foams are discussed in the last two chapters. Among other topics the concept of the spontaneous curvature and its importance of surfactant films is developed and ways to stabilize and destabilize emulsions are discussed. All chapters include a so-called “concept map“ in which the most important results of the chapter are summarized. These concept maps are very helpful in order to recall what was discussed, especially when one takes the book out of the shelves some time later. To conclude “The Colloidal Domain“ is an excellent text book in this field with a special emphasis on surfactant systems. It can be recommended for students but also for scientists and engineers who need to learn more about this topic (which is often neglected in the curricula). The second edition has been substantially revised. New topics have been added and some chapters have been reorganized. So it can be recommended also for those who already own the first edition.