ABSTRACT

That colloidal dispersions of nanoparticles are often used as concentrated slurries is a well-known fact, particularly when industrial applications are in mind. Suffice it to say that volume fractions as high as 50% can be found in ceramic suspensions, and that when drug particles are administered as dispersions, therapeutic levels require values as high as 30% (Alejo and Barrientos 2009; Beirowski et al. 2012; Johnson et al. 2000; Vauthier et al. 2008). Although a number of techniques are available

14.1 Introduction .................................................................................................. 313 14.2 The Spherical Particle Case .......................................................................... 315

14.2.1 General Features ............................................................................... 315 14.2.2 How Can the Permittivity and Dynamic Mobility Be Obtained? .... 322 14.2.3 Some Results ..................................................................................... 323

14.2.3.1 Dielectric Spectroscopy ..................................................... 323 14.2.3.2 Dynamic Mobility .............................................................. 327 14.2.3.3 Comparison with Experiment ............................................ 329

14.3 Models Not Based on the Cell Approach ..................................................... 330 14.4 The Case of Soft and Brush Particles ........................................................... 333

14.4.1 Soft Particles ..................................................................................... 333 14.4.1.1 Model ................................................................................. 334 14.4.1.2 Representative Results ....................................................... 335

14.4.2 Polyelectrolyte Brushes .................................................................... 338 14.5 Non-Spherical Geometries ........................................................................... 341

14.5.1 Models .............................................................................................. 341 14.5.2 Representative Results ......................................................................344