Kinetics of Formation of Quasi-Monodisperse Micelles

A new kinetic model of formation of quasi-monodisperse micelles is proposed, preserving the main relaxation features of the polydisperse micellers. Two kinds of co-existing monodisperse micelles are considered: q-micelles and p-micelles. During the fast process some of p-micelles. releasing Δp = p - q monomers, transform into q-micelles (or vice versa). During the slow relaxation process the micelles destroy or form to reach the final equilibrium. Expressions for the relaxation times of these two processes and for the concentrations of the free monomers and the micelles are obtained by means of an asympotic method. The solutions in the inner time domain (fast process) and the outer one (slow process) are matched and thus an uniformly valid solution is found. The quasi-monodisperse model is consistent with the polydisperse one if thc q- and p-micelles have equal equilibrium concentrations and Δp is the width of the miceller size distribution.