Modified polyether glycols supported ionic liquids for CO2 adsorption and chemical fixation

Hydroxyl polyether-grafted imidazolium ionic liquids (HPEG(n)RIMX) have been synthesized by a chemical stoichiometric method, which were applied into strengthening CO2 accessibility and conversing CO2 into cyclic carbonates. The structure was determined by FT-IR, NMR, TGA and MS. Under the optimum reaction conditions of 1.0 mol% HPEG(n)RIMX, 2.0 MPa CO2 pressure, 130 degrees C and 1.5 h, it could achieve excellent catalytic activities. The performance was over than that of PEG(400)DEIMBr with double terminal ending-capped ILs functional groups due to its multifunctional synergestic roles including the long polyether chains, hydrogen-bonding between hydroxyl groups on HPEGnILs and oxygen atoms on cyclo-epoxides, and the halide anionic nuclephilicity. The mechanism was further investigated by IGA and in-situ NMR spectrum.