Nanostructuring of Bridged Organosilane Precursors with Pendant Alkyl Chains

Abstract

AbstractThe copper‐catalyzed alkyne azide cycloaddition (CuAAC) reaction was combined with sol‐gel reactions for the production of bridged silsesquioxanes (BSs) in which hexyl and icosanyl chains are pendant and anchored on a single position to a triazole ring. The influence of the alkyl chain length on the structure of the BSs, represented by the notation Cn/siloxane (where n = 6 and 20), was examined. The C20/siloxane hybrid is a hydrophobic material that exhibits a hierarchically structured lamellar bilayer organization, a texture composed of microplates of nanometer thickness, and a reversible time‐independent order/disorder phase transition (onset at 60 °C). The driving forces for self‐assembly are van der Waals interactions between the icosanyl chains and π‐π interactions between the triazole rings. In the essentially amorphous C6/siloxane hybrid, the latter contribution promotes the genesis of a pre‐lamellar phase similar to that found in C20/siloxane.