(108a) Nanoscale Organic Hybrid Materials - Multiscale Structure and Dynamics

Soft colloids have attracted significant interest as model systems for studying glassy fluid structure and dynamics. This attraction arises in part from their less fragile behavior when compared to hard sphere colloids and their ability to reach equilibrium even when in a jammed state. This talk focuses on structure and dynamics of a class of soft colloids created by densely grafting oligomers or ionic liquid molecules to inorganic nanoparticles. Termed Nanoscale organic hybrid materials (NOHMs), these materials form stable, self-suspended suspensions, which allow glassy fluid physics, rheology, and structure to be studied without complications from enthalpic interactions between a solvent and the suspended phase. The effect of “softness” and confinement on the structure and dynamics of the nanoparticle cores and polymeric corona in NOHMs are explored in the talk. In particular, by varying the molecular weight, grafting density, and chemistry of the tethered polymer chains it is shown that jammed materials can be designed with tunable softness, elastic moduli, and ion transport properties that are all strong functions of particle curvature. By manipulating the size and chemistry of the tethered molecules, we further show that the materials can be used as model nanoparticle additives in polymeric hosts to study phase behavior and dynamics.