Mixtures of Diblock Copolymer Micelles by Different Mixing Protocols

A size distribution of a binary mixture of polystyrene- block -poly(4-vinylpyridine) (PS−P4VP) diblock copolymer micelles was investigated mainly by transmission electron microscopy. A single-layered film of PS−P4VP micelles fabricated by spin-coating enabled a precise measurement of the micellar size. Depending on the mixing protocols, a mixture of pristine small and large micelles or a mixture of pure small micelles and hybridized micelles were formed due to the difference in the kinetics of micelle formation between the copolymers having short and long insoluble P4VP blocks. In addition, the kinetically frozen micelles excluded further evolution of the micelles produced. We also demonstrated feasible creation of an ordered array of copolymer micelles with the mixing protocol which produced nonhybridizing micelles.