Facile synthesis of polymerized ionic liquids with high thermal stability

Twelve main-chain-type polymerized ionic liquids that have alkylimidazolium cation units were prepared using simple synthetic processes. The polymers were prepared using the self-polymerization of a single monomer; no polymerization initiators were required. The thermal stability and solvent miscibility of these polymers were studied. Results show that the combined anions greatly influence the solubility and thermal stability of the polymers. Among these polymers, poly-alkylimidazolium bis(trifluoromethylsulfonyl)imide polymers exhibited the highest thermal stability (>400 °C), which makes them candidates for many applications.

Thermal gravimetric analysis of the proposed polymerized ionic liquids.