Ionic liquids (ILs) are a promising medium to assist in the advanced (chemical and biological) recycling of polymers, owing to their tunable catalytic activity, tailorable chemical functionality, low vapor pressures, and thermal stability. These unique physicochemical properties, combined with ILs’ capacity to solubilize plastics waste and biopolymers, offer routes to deconstruct polymers at reduced temperatures (and lower energy inputs) versus conventional bulk and solvent-based methods, while also minimizing unwanted side reactions. In this Viewpoint, we discuss the use of ILs as catalysts and mediators in advanced recycling, with an emphasis on chemical recycling, by examining the interplay between IL chemistry and deconstruction thermodynamics, deconstruction kinetics, IL recovery, and product recovery. We also consider several potential environmental benefits and concerns associated with employing ILs for advanced recycling over bulk- or solvent-mediated deconstruction techniques, such as reduced chemical escape by volatilization, decreased energy demands, toxicity, and environmental persistence. By analyzing IL-mediated polymer deconstruction across a breadth of macromolecular systems, we identify recent innovations, current challenges, and future opportunities in IL application toward circular polymer economies. 
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                            Single‐molecule fluorescence microscopy for imaging chemical reactions: Recent progress and future opportunities for advancing polymer systems
                        
                    
    
            Abstract Single‐molecule fluorescence (smFL) imaging techniques have evolved greatly over the past two decades to encompass the ability to monitor chemical reactions, providing unique advantages of non‐invasive sample preparation and characterization, labeling specificity, and high spatial and temporal resolutions. This work summarizes the recent progress in this important area by first providing a brief overview of different smFL techniques, including their common optical setups and working principles. We then introduce recent developments of smFL to characterize various model chemical reaction systems, such as biochemical synthesis, catalyzed systems, and nanomaterial assembly. Furthermore, several representative areas of using smFL to understand polymer reactions are discussed, including understanding interfacial phenomenon and polymerization kinetics, as well as characterizing electrochemical reactions. We also highlight the outlook of this exciting field and potential opportunities for further development and application of smFL to enable advances in polymer chemistry and physics. 
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                            - Award ID(s):
- 2132144
- PAR ID:
- 10568694
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 62
- Issue:
- 7
- ISSN:
- 2642-4150
- Page Range / eLocation ID:
- 1235 to 1259
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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