A novel room-temperature ionic liquid (RTIL),1-allyl,3-methylimidazolium chloride (［AMIM］Cl),was synthesized,ch aracterized and used for dissolving cellulose.The solubility of cellulose in ［ AMIM］Cl was better than in 1-butyl,3-methylimidazolium (［BMIM］Cl).The pris tine cellulose and two cellulose samples regenerated from ［AMIM］Cl and ［BMIM ］Cl solutions were compared by FTIR,WAXD and TGA measurements.Results show t hat these two RTILs are non-derivatizing solvents for cellulose.After regenera tion from RTIL solutions,the crystalline form of cellulose films is completely transformed from cellulose Ⅰ to cellulose Ⅱ.Compared to pristine cellulose,t he regenerated cellulose exhibits a lower onset temperature of thermal decomposi tion,with a higher char yield.
Homogeneous acetylation of cellulose in 1-allyl-3-methyl-imidazolium chloride(AMIMCl) was carried out. Acetic anhydride and acetyl chloride were used as acetylating agents in the absence and presence of pyridine. The degree of substitution(DS) of the products and the distribution of substituents were determined by titration and {} 13C NMR techniques respectively. It was observed that acetyl chloride reacted faster than {anhydride}. Further, pyridine accelerated the reactions when anhydride was used as the acetylating agent, while it slowed down the reactions when acetyl chloride was used. An interesting distribution of DS_ C-2 DS_ C-3 for substitutes was observed in the product with acetic anhydride/pyridine system.
