L.J.: Mechanics and microstructures of concentrated particle gels

It is often assumed that the viscoelastic properties of dense col-loids are determined by the colloid volume fraction, the inter-action potential, as well as the particle size distribution and shape. The dependence of the viscoelastic behavior of particle suspensions and gels on these parameters has been widely stud-ied, and is well understood in many cases. In contrast, our knowledge on the influence of microstructure on mechanical and rheological properties, in particular for high solid loading sus-pensions as used in ceramic processing, is much less developed. This aspect has been the focus of recent experiments, which show that small changes in microstructure can have dramatic effects on the mechanics and dynamics of concentrated colloidal gels. In this article, we attempt to give an overview of the influ-ence of microstructure on the mechanical and rheological prop-erties of colloidal systems. Particular attention is given to colloidal particle gels at high volume fractions. I