PROGRESS INORGANIC COATINGS ELSEVIER
Progress in Organic Coatings 26 (1995) 75-76
Book Review Interfacial Forces in Aqueous Media By C.J. van Oss, published by Marcel Dekker, New York, 1994, US$ 165
Interfacial interactions are crucially important for many properties of both solvent- and waterborne organic coatings as well as for their liquid predecessors. The theoretical treatments of these interactions, however, was not yet gained much practical relevance, because of the great variety and the complex composition of both paint systems and their substrates. In the present book, the author distinguished four primary non-covalent interactions, which operate in condensed media: electrodynamic (Lifshiz-van der Waals) forces; electrostatic (Coulomb) forces; acid-base (electron donor-acceptor) or polar forces, including hydrogen bonds; and Brownian movement (thermal) interactions. By this classification, the subject becomes more concise and lucid as compared with older textbooks in this field. The emphasis is laid on aqueous systems, which makes this book especially interesting to organic coatings, considering the growing importance of water as a solvent or medium. In Part I, theories of the four interactions are critically discussed, regarding the present state of art and also the rate of their decay with distance. Part II treats the experimental methods for measuring interfacial forces. The author gives strong preference to.measuring contact angles and determining surface and interfacials tensions for evaluating interfacial forces and also discusses electrokinetic methods, relations between the Hamaker constant and the apolar surface tension component as well as some direct measuring methods. Associated phenomena and applications are also discussed. Here, the author correlates well-known intermolecular and interfacial phenomena, such as solubility and phase separation, dispersion stability, adsorption, adhesion and surface tension. This discussion is both valuable and unique and is distinguished by competence as well as by a critical distance. The reader feels that the author knows his subject excellently. A number of frequently used, but not always sufficiently well understood, conceptions, such as steric repulsion, entropic stabilization, hydrophobic interactions and hydration pressure are explained and critically discussed. A not very usual feature is, that each chapter ends with a short summary of the more important relations and statements. Unfortunately for paint scientists, the practical examples for illustrating the arguments are mostly taken from biochemistry, biopolymers and cells. As to adhesion, it could be wished that the influence of chain mobility and rigidity of the substrate on bond stabilization be treated. The paint chemists and technologists miss an Elsevier Science S.A.
76
extension the basics The book this book
Book Review/Progress
in Organic Coatings 26 (1995) 75-76
to their field especially in the chapter on adsorption and adhesion. However, as of both fields are the same, this omission does not lessen the value of this book. ends with comprehensive lists of symbols and literature. Of course, the price of is high, but not unjustified. W. Funke Leonberg, Germany