Nanosize Aggregates of Block Copolymers of Styrene and Hydrogenated Butadiene in Water

Abstract
Three-block copolymer polystyrene-block-hydrogenated polybutadiene-block-poly-styrene forms micelles with aliphatic cores and polystyrene shells in dioxane. When a solution of these micelles with an appropriate stabilizer (e.g., a block copolymer of ethylene oxide and propylene oxide) is injected into excess water, a stable dispersion results. The resulting particles have a hydrodynamic radius around 55 nm and particle molecular weight is hundreds of millions. The mechanism of the particle formation and their structures are discussed.