Self-assembly of arborescent polystyrene-graft-poly(ethylene oxide) copolymers at the air/water interface

AFM imaging was used to investigate the influence of molecular structure and composition on the formation of Langmuir monolayers by arborescent PS-graft-PEO copolymers at the air/water interface. Even without compression, these molecules associate spontaneously at the air/water interface and form stable monolayers that are easily transferred onto solid substrates as Langmuir/Blodgett films. The copolymers either form aggregates with a low association level, large island-like clusters, or ribbon-like superstructures. The different behaviors of the copolymers are rationalized in terms of the influence of their composition and of the structure of the arborescent PS cores on the the assembly process.