This book covers the physical side of colloidal science from the individual forces acting between particles smaller than a micrometer that are suspended in a liquid, through the resulting equilibrium and dynamic properties. A variety of internal forces both attractive and repulsive act in conjunction with Brownian motion and the balance between them all decides the phase behaviour. On top of this various external fields, such as gravity or electromagnetic fields, diffusion and non-Newtonian rheology produce complex effects, each of which is of important scientific and technological interest. The authors aim to impart a sound, quantitative understanding based on fundamental theory and experiments with well-characterised model systems. This broad grasp of the fundamentals lends insight and helps to develop the intuitive sense needed to isolate essential features of the technological problems and design critical experiments. The main prerequisites for understanding the book are basic fluid mechanics, statistical mechanics and electromagnetism, though self contained reviews of each subject are provided at appropriate points. Some facility with differential equations is also necessary. Exercises are included at the end of each chapter, making the work suitable as a textbook for graduate courses in chemical engineering or applied mathematics. It will also be useful as a reference for individuals in academia or industry undertaking research in colloid science.

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Thin films of latex dispersions containing particles of high glass transition temperature generally crack while drying under ambient conditions. Experiments with particles of varying radii focused on conditions for which capillary stresses normal to the film deform the particles elastically and generate tensile stresses in the plane of the film. Irrespective of the particle size, the drying film contained, simultaneously, domains consisting of a fluid dispersion, a fully dried packing of deformed spheres, and a close packed array saturated with water. Interestingly, films cast from dispersions containing 95-nm sized particles developed tensile stresses and ultimately became transparent even in the absence of water, indicating that van der Waals forces can deform the particles. Employing the stress-strain relation for a drying latex film along with the well-known Griffith's energy balance concept, we calculate the critical stress at cracking and the accompanying crack spacing, in general agreement with the observed values.