2013/03/14 by Alessio Zaccone, Jerome J. Crassous, Jérôme J. Crassous +1 · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Material Dynamics and Properties #Pickering emulsions and particle stabilization #Surfactants and Colloidal Systems #cond-mat.soft
paper · pdf · doi:10.1063/1.4794695
published as Journal of Chemical Physics 138, 104908 (2013)
openalex publication_date 2013/03/14 · arxiv created 2013/04/04 · arxiv updated 2013/04/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present an approximation scheme to the master kinetic equations for aggregation and gelation with thermal breakup in colloidal systems with variable attraction energy. With the cluster fractal dimension df as the only phenomenological parameter, rich physical behavior is predicted. The viscosity, the gelation time, and the cluster size are predicted in closed form analytically as a function of time, initial volume fraction, and attraction energy by combining the reversible clustering kinetics with an approximate hydrodynamic model. The fractal dimension df modulates the time evolution of cluster size, lag time and gelation time, and of the viscosity. The gelation transition is strongly nonequilibrium and time-dependent in the unstable region of the state diagram of colloids where the association rate is larger than the dissociation rate. Only upon approaching conditions where the initial association and the dissociation rates are comparable for all species (which is a condition for the detailed balance to be satisfied) aggregation can occur with df = 3. In this limit, homogeneous nucleation followed by Lifshitz-Slyozov coarsening is recovered. In this limited region of the state diagram the macroscopic gelation process is likely to be driven by large spontaneous fluctuations associated with spinodal decomposition.