Giant Surfactants based on Precisely Functionalized POSS Nano-atoms: Tuning from Crystals to Frank-Kasper Phases and Quasicrystals

COFFEE_KLATCH · Invited

Abstract

In creating new functional materials for advanced technologies, precisely control over functionality and their hierarchical ordered structures are vital for obtaining the desired properties. Giant polyhedra are a class of materials which are designed and constructed via deliberately placing precisely functionalized polyhedral oligomeric silsesquioxane (POSS) and fullerene (C$_{\mathrm{60}})$ molecular nano-particles (MNPs) (so-called ``nano-atoms'') at the vertices of a polyhedron. Giant surfactants are consisted of polymer tail-tethered ``nano-atoms'' which are deliberately and precisely functionalized POSS or C$_{\mathrm{60}}$ molecular nano-particles (MNPs). The ``nano-atom'' heads and polymer tails thus have drastic chemical differences to impart amphiphilicity. These giant surfactants capture the essential structural features of their small-molecule counterparts in many ways but possess much larger sizes, and therefore, they are recognized as size-amplified versions of small molecule surfactants. Two of the most illustrating examples are a series of novel giant tetrahedra and a series of giant giant surfactants as building blocks to construct into hierarchical ordered super-lattice structures ranging from crystals, Frank-Kasper phases and quasicrystals in the condensed bulk states, reveals evidently the interconnections between soft matters and hard matters in sharing their common structures and fundamental knowledge.

Authors

  • Stephen Z. D. Cheng

    University of Akron