AGGREGATION PHENOMENA

We report on low-angle static light scattering measurements on colloid al aggregation of polystyrene latex particles. Measurements have been performed both at low and high monomer concentrations. Pure diffusion limited cluster aggregation (DLCA) have been investigated in the dilut e regime. The predicted power-law growth of the radius has been observ ed. Spurious effects due to the presence of gravity are reported. Meas urements on the high concentration samples show an unexpected and quit e novel phenomenon. A peak in the scattering pattern whose position q( m) moves towards smaller q-values and whose height grows in time has b een observed. We have found that the scattering distributions can be s caled onto the same master curve with a scaling law strongly reminisce nt of that working in the completely different case of spinodal decomp osition.