Controlling Orientation and Functionalization in Thin Films of Block Copolymers

Functionalizing and controlling nanostructures resulting from block copolymer self-assembly are key factors in defining their application. In this work, a simple but quite general route to achieve both goals simultaneously is discussed. In thin films of polystyrene-block-poly(vinyl pyridine) (PS-b-PVP) with small concentrations of a gold salt, the salt is found to complex with the PVP block which leads to an orientation of the microdomains normal to the surface after solvent annealing together with functionalization. By increasing the amount of gold salt, on the other hand, micelles are found to form in solutions leading to a range of different morphologies in the thin films.