Here, we provide a detailed report on a new type of structured media for improving photopolymerizations: coordinated ionic liquids (ILs). Coordinated ILs are readily formed from the bistriflimide ([Tf 2 N] 2 ) anion and coordination complexes composed of Li 1 cations with polar organic monomers without an additional cosolvent. Photopolymerization kinetics and monomer conversion were monitored in real time using attenuated total reflectance Fourier transform infrared spectroscopy and the material properties of the products were examined using gel permeation chromatography and differential scanning calorimetry. Generally, coordinated IL monomers displayed improved reaction kinetics at both high and low salt concentrations as well as distinct product properties. The noncovalent (and reversible) interactions between monomer and salt in coordinated ILs hold promise as an efficient and versatile form of structured media for photopolymerizations.

Coordinated ionic liquid (IL) monomers provide many of the benefits of conventional ILs in radical polymerization with the advantage of relatively simple synthesis and recovery of the polymer product. Previous studies have reported high solubilities of lithium bistriflimide in polar organic monomers such as methyl methacrylate (MMA), 1‐vinylimidazole (VIm) and others. Here, coordinated IL monomers are formed comprising a variety of alkali and alkaline earth Mn+(Tf2N−)n salts with MMA and VIm, and polymerization behavior is investigated using real‐time attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT‐IR). The size and valency of the coordinated Mn+ cations are observed to strongly influence monomer reactivity, as evidenced by significant changes in FT‐IR spectra. This work further demonstrates that the bulky, delocalized [Tf2N]− anion allows for facile introduction of a wide range of Mn+ cations into organic polymers without phase separation, which may open opportunities for new composite materials.

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