and then extracted with acetone for 24 h to remove BMIMCl and unreacted modifier. Finally, the modified cellulose were washed with distilled water again and dried at 60 ◦ C for 24 h in a vac- uum oven, which were named as cellulose-g-urea, cellulose-g-PA, cellulose-g-MA, cellulose-g-BGE and regenerated cellulose, respec- tively.