Ionic liquids and poly(ionic liquid)s for 3D printing - A focused mini-review

Ionic liquids are a class of materials with unique physicochemical properties and intriguing preorganized and tunable solvent structures. Recent usage of ionic liquids as precursors, templates, and solvents has led to polymeric materials with tailored sizes, dimensionalities, morphologies, and functionalities that are difficult to achieve by employing common organic solvents. Ionic liquid monomers from unique macromolecules-known as poly(ionic liquid)s or polymerized ionic liquids-that incorporate cationic and/or anionic sites either pendant to or within the polymer backbones. Poly(ionic liquid)s have recently attracted increasing interest across a wide range of applications, e.g., thermo-responsive materials, carbon materials, catalysis, porous polymers, separation and absorption materials, and energy harvesting and generation as well as biological applications. This review presents a literature survey of recent work on three-dimensional (3D) printing technology over the past few years, highlighting the unique features of ionic liquids and poly(ionic liquid)s in emerging applications of 3D printing. Finally, we provide an overview of several development opportunities that could lead to new advancements in this exciting research field.