title: Per-O-acetylation of cellulose in dimethyl sulfoxide with catalyzed transesterification.
abstract: Cellulose acetylation was investigated in dimethyl sulfoxide (DMSO) with isopropenyl acetate (IPA) as acetylating reagent and 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) as catalyst at 70-130 °C for 3-12 h. The degree of substitution (DS) of acetylated cellulose was comparatively determined by titration and ¹H NMR and confirmed by FT-IR analysis. The results indicated that per-O-acetylation was achieved at >90 °C for a relatively long duration. The three well-resolved peaks of carbonyl carbons in ¹³C NMR spectra also provided evidence of per-O-acetylation. The solubility of cellulose acetates in common organic solvents was examined, and the result showed that chloroform can be an alternative choice as a solvent for fully acetylated cellulose formed in this study besides DMSO. The intrinsic viscosity of acetylated cellulose solution implied almost no degradation of cellulose during acetylation in DMSO except at higher temperature (130 °C) for a long time.
authors.affiliation: State Key Laboratory of Pulp and Paper Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Chao-Yi
authors.initials: CY
authors.lastname: Chen
authors.forename: Ming-Jie
authors.initials: MJ
authors.lastname: Chen
authors.forename: Xue-Qin
authors.initials: XQ
authors.lastname: Zhang
authors.forename: Chuan-Fu
authors.initials: CF
authors.lastname: Liu
authors.forename: Run-Cang
authors.initials: RC
authors.lastname: Sun
mesh_terms: D000085:Acetates / Q000737:chemistry; D000107:Acetylation; D002384:Catalysis; D002482:Cellulose / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D004951:Esterification
chemical_list: D000085:Acetates; C555950:isopropenyl acetate; D002482:Cellulose; D004121:Dimethyl Sulfoxide