Two mixtures separate into two phases and are then left to coarsen.
PHYSICS · Multi-part · Fermi University Physics · Thermal, Statistical & Complex Systems · Condensed Matter, Materials & Soft Matter · Non-equilibrium statistical mechanics and stochastic thermodynamics
Soft Matter at the Thermal Scale, Ch Spinodal decomposition and coarsening
Problem
Two mixtures separate into two phases and are then left to coarsen.
((a)) A silicone-oil-in-water emulsion with oil volume fraction ϕ=0.02, stabilised against creaming, is left to ripen for several days.
((b)) A blend of two chemically similar homopolymers with volume fractions 0.48:0.52 is quenched deep into the two-phase region and observed over several hours. For each, predict whether the late-stage coarsening is Lifshitz-Slyozov (diffusive) ripening or hydrodynamic (flow-driven) coarsening, and justify the choice from the morphology of the domains. For case (b), also explain in words why the domain size eventually grows linearly in time rather than as t1/3.