2.2 Preparation and Characterization of PILs
These PILs were synthesized by neutralization reaction. Taking a typical run, 50 mL of the ethanol solution of MeOAc (20 mmol) was added dropwisely to the ethanol solution of BDMAEE (25 mmol). The reaction was stirred in an ice bath until it was raised to room temperature and stirred for 12 hours. Then, ethanol was removed by vacuum distillation and the remaining crude product was washed three times by diethyl ether to remove the excess reactant. The product was dried in a vacuum at 60 ÂșC for 24 hours to remove trace solvents, and finally, a clear liquid [BDMAEEH][MeOAc] was obtained.