Water-enriched poly(ionic liquid)s: highly-efficient microreactors for the hydrolysis of ethylene carbonate

Poly(ionic liquid) (PIL) catalysts with swelling ability and water enrichment ability in water/ethylene carbonate (EC) mixed substrates were designed and synthesized via a one-step direct radical copolymerization of N-vinylimidazolium IL monomers, sodium acrylate and crosslinkers. The structure and morphology of the PILs were characterized by NMR, FT-IR, TGA, SEM and elemental analysis. The effect of substituent groups and crosslinkers on the swelling ability and water enrichment ability of PILs in water and EC was studied. The water enrichment ability of PILs was positively related to the hydrophilicity of 3-substituents on imidazoliums and the crosslinkers, and water could be absorbed inside quantitatively. These PIL catalysts could enrich the optimal ratio of water to EC inside and act as high-efficiency microreactors for the catalytic hydrolysis of EC. The water enrichment ability of PIL microreactors was helpful for the decrease of water amount and the increase of catalytic efficiency.