Dissolution of microcrystalline cellulose and its graft copolymer in ionic liquid of 1-allyl-3-ethylimidazolium chloride

The ionic liquid of 1-allyl-3-ethylimidazolium chloride ([AEIM]Cl) was synthesized and its chemical structure was confirmed. Dissolution of microcrystalline cellulose (MCC) in [AEIM]Cl by microwave heating method was researched. Acrylamide (AM) was grafted onto the dissolved MCC with initiator in [AEIM]Cl and aqueous medium respectively. The effect of temperature, initiator and its dosages on monomer conversion and grafting efficiency was studied. The results showed that [AEIM]Cl was a good solvent for MCC and dissolution rate was the highest (28.8%) when the MCC pretreated with 15% NaOH under the high pressure. Graft copolymer prepared by AM and MCC in [AEIM]Cl had higher monomer conversion and grafting efficiency than in aqueous medium. The best condition for preparing graft copolymer was that potassium persulfate was used as initiator with the dosage of 1g/L under the temperature of 45 °C-50 °C. Spectra of FT-IR had proved that AM was grafted onto MCC. The thermal stability of MCC improved after grafting, and the crystal form was destroyed thoroughly.