Self-Assembled Structures of Giant Surfactants Exhibit a Remarkable Sensitivity on Chemical Compositions and Topologies for Tailoring Sub-10 nm Nanostructures

Abstract

We report a remarkable sensitivity of self-assembled structures of giant surfactants on their chemical compositions and molecular topology, which facilitate the engineering of various nanophase-separated structures with sub-10 nm feature sizes. Two classes of giant surfactants composed of various functionalized polyhedral oligomeric silsesquioxane (POSS) heads tethered with one or two polystyrene (PS) tails were efficiently prepared from common precursors of vinyl-substituted POSS–PS conjugates via one-step “thiol–ene” postpolymerization functionalization. With identical molecular weights of the PS tails, the resulting giant surfactants exhibited distinct highly ordered phases, as evidenced by small-angle X-ray scattering and transmission electron microscopy observations. Moreover, comparison between the topological isomers revealed that the self-assembled structures are also highly sensitive to molecular topology. Introduction of two PS tails with half-length not only shifted the boundaries between diffe...