Shear-induced orientation of gyroid PS-b-P4VP(PDP) supramolecules

摘要

The phase behavior of block copolymer based supramolecular complexes polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) and amphiphilic pentadecylphenol (PDP) molecules resembles the phase behavior of conventional block copolymers. Several PS-b-P4VP(PDP) complexes are found to self-assemble into gyroid nanostructures. Typically, the grains are randomly oriented with a maximal size of several micrometers. Here, the orientation of a gyroid PS-b-P4VP(PDP) complex upon shearing is reported. It is found that the (111) gyroid lattice direction orients parallel to the shear direction after only several seconds of large amplitude oscillatory shearing. Oriented gyroid complexes can be used as templates for the preparation of metal nanofoams with improved ordering with potentially superior properties. Several supramolecular complexes PS-b-P4VP(PDP) are found to self-assemble into ordered gyroid morphology, which can be replicated to various inorganic materials. Here, we examine the influence of large amplitude oscillatory shear on the phase behavior of these complexes. We find that upon LAOS, gyroid complexes orient with their (111) direction parallel to the shear direction. The oriented gyroid complexes can be used as precursors to highly ordered and oriented inorganic materials with possibly superior properties in comparison with the existing ones.