On the relationship between rheology and percolation in the gelation of weakly attractive colloids: Beyond "snapshot" percolation

A discussion on the viscoelastic properties of weakly attractive colloids and the relation to a newly developed percolation theory is presented. The need for taking into account the particle-particle bond lifetime in order to compare rheological and percolation estimates of the sol-gel transition is stressed. Recent molecular dynamics simulations and generalised percolation theory that use a bond lifetime criterion in the definition of aggregates show that the percolation transition can be reconciled with the rheological sol-gel transition. The percolation concept is used here as a "measuring" tool to assess the viscoelastic behaviour of the system.