(122d) Supramolecular Hydrogels: Simple Processing, Remarkable Properties

Co-polymerization of common hydrogel monomers, such as acrylamides, with hydrophobic monomers prevents dissolution of these polymers in water due to the aggregation of the hydrophobic moieties that provide physical crosslinks. In this case, the hydrophobic domains consist of 2-(N-ethylperfluorooctane sulfonamido)ethyl acrylate (FOSA), which aggregate into sub-10 nm domains in the hydrogels. As the polymer is not chemically crosslinked, these copolymers can be readily processed via extrusion. We will illustrate the ability of these materials to easily form 3D fiber mats through electrospinning as well as free-form object by 3D printing using FDM. Moreover, these hydrophobic domains lead to intriguing properties that can be readily tuned by the FOSA content. These hydrogels can be extremely tough, exhibit self-healing properties and suppress ice formation on cooling. We will show evidence for 5 distinct flavors of water within these hydrogels on cooling to 190 K. We will discuss how tuning the concentration of the hydrophobic composition of the hydrogel affects the state of water and the ice produced by supercooling.