ORDERED COARSENING IN COLLOIDAL AGGREGATION

We present low-angle light scattering data on aggregation runs of dens e colloidal systems. We show that the scattered pattern exhibits a pea k at finite wavevectors if the reaction occurs in a diffusion limited regime, and universal scaling similar to that of spinodal decompositio n applies. If the runs are made under conditions closer to reaction li mited behaviour, however, the peak appearance is delayed until it is e ventually lost altogether.