Ionic Liquid Facilitated Introduction of Functional Materials into Biopolymer Polymer Substrates

In the past decade, ionic liquid solvents have been developed for a wide variety of biopolymers such as cellulose and silk. During this time ionic liquids have also been shown to enhance the interactions of micromaterials and nanomaterials (i.e., clays, carbon nanotubes, magnetic materials, et cetera) with polymeric materials. Recently, our group has demonstrated an ionic liquid-based technique, “Natural Fiber Welding”, by which functionalized composite materials are generated from (often fibrous) biopolymer substrates. Fiber welding processes leverage many of the advantageous properties of ionic liquids as solvents and compatibilization media. A distinctive characteristic of the fiber welding process is the selective mobilization and restructuring of biopolymers to create composite materials that retain native biopolymer microstructures and mesostructures. As ionic liquid solvents penetrate fiber surfaces, biopolymers are opened to chemical derivatization; simultaneously, hydrogen bonding networks are reorganized (and extended).