Abstract
The static and hydrodynamic properties of micelles formed by (PS)8(PI)8 16-miktoarm (Vergina) star copolymers in the selective, for the PI arms, solvent n-decane were studied. Static and dynamic light scattering and viscometry were employed to determine the aggregation number, the size, and shape of the micelles in dilute solutions. All samples formed multimolecular micelles in n-decane. For the low molecular weight symmetric sample, experiments indicate that the micelles have a more elongated shape. As the compositional asymmetry increased in favor of the soluble branches, the micelles become more spherical. In comparison to linear diblocks with block lengths equal to the lengths of the respective branches, miktoarm stars order into micelles of lower aggregation number and larger dimensions. The area, on the core-corona interface, per junction point was found to be larger in the miktoarm stars. The differences can be attributed to the differences in architecture and the additional constraints imposed by a common junction point in these highly branched miktoarm stars, which influence the organization of the macromolecules into stable micellar structures in solution.