| Abstract
| - The evolution of polymolecular micelles formed by two different poly(2-vinylpyridine)−polystyrene (PVP−PS) block copolymers dissolved in toluene is studied by means of transmission electronmicroscopy (TEM). The two PVP−PS diblock copolymers differ in composition, namely in the length ofPVP block. Upon dissolution, a rapid formation of mixed polymolecular micelles takes place. As a result,the micellar size distribution observed is rather broad already at this initial stage. Due to the presenceof two different diblock copolymers, the process of micellar growth involves not only the fusion of micellesbut also the chain exchange between polymolecular micelles of different composition, which may slowthe equilibration process. After a considerable aging time, the block copolymers seem to reach theequilibrium state, and an almost perfect bimodal size distribution is observed. According to the theoreticalanalysis given, both “pure” and “mixed” micelles constitute the micellar size distribution.
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