title: Structural features of lignin macromolecules extracted with ionic liquid from poplar wood.
abstract: 1-Ethyl-3-methylimidazolium acetate ([Emim][CH₃COO]) was used for the extraction of lignin from poplar wood (Populus albaglandulosa), which was called to ionic liquid lignin (ILL) and structural features of ILL were compared with the corresponding milled wood lignin (MWL). Yields of ILL and MWL were 5.8±0.3% and 4.4±0.4%, respectively. The maximum decomposition rate (V(M)) and temperature (T(M)) corresponding to V(M) were 0.25%/ °C and 308.2 °C for ILL and 0.30%/ °C and 381.3 °C for MWL. The amounts of functional groups (OMe and phenolic OH) appeared to be similar for both lignins; approximately 15.5% and 6.7% for ILL and 14.4% and 6.3% for MWL. However, the weight average molecular weight (M(w)) of ILL (6347 Da) was determined to be 2/3-fold of that of MWL (10,002 Da) and polydispersity index (PDI: M(w)/M(n)) suggested that the lignin fragments were more uniform in the ILL (PDI 1.62) than in the MWL (PDI 2.64).
authors.affiliation: Department of Forest Sciences and Research Institute for Agriculture and Life Science, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-921, Republic of Korea.
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Eun-Jin
authors.initials: EJ
authors.lastname: Shin
authors.forename: In-Yong
authors.initials: IY
authors.lastname: Eom
authors.forename: Keehoon
authors.initials: K
authors.lastname: Won
authors.forename: Yong Hwan
authors.initials: YH
authors.lastname: Kim
authors.forename: Donha
authors.initials: D
authors.lastname: Choi
authors.forename: In-Gyu
authors.initials: IG
authors.lastname: Choi
authors.forename: Joon Weon
authors.initials: JW
authors.lastname: Choi
mesh_terms: D002850:Chromatography, Gel; D007093:Imidazoles; D052578:Ionic Liquids / Q000737:chemistry*; D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D032107:Populus / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013818:Thermogravimetry
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D008031:Lignin; C518739:1-ethyl-3-methylimidazolium