Homogeneous esterification of xylan-rich hemicelluloses with maleic anhydride in ionic liquid.
Generation of bioenergy, new functional polymers, or chemicals and biomaterials from hemicelluloses are important uses for biomass. In this paper, a novel functional biopolymer with carbon-carbon double bond and carboxyl groups was prepared by a homogeneous esterification of xylan-rich hemicelluloses (XH) with maleic anhydride in 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid using LiOH as catalyst. The biopolymers with degrees of substitution (DS) between 0.095 and 0.75 were accessible in a completely homogeneous system by changing reaction temperature, reaction time, the dosage of catalyst, and the molar ratio of maleic anhydride to anhydroxylose unit in XH. Results obtained from FT-IR and (13)C NMR spectroscopies confirmed the structure of hemicellulosic derivatives with carbon-carbon double bond and carboxyl groups, implying an efficient method to prepare a novel and important functional biopolymer for biomaterials.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, China.
Xin-Wen
XW
Peng
Jun-Li
JL
Ren
Run-Cang
RC
Sun
D001704:Biopolymers; D004951:Esterification; D052578:Ionic Liquids; D008299:Maleic Anhydrides / Q000737:chemistry*; D015394:Molecular Structure; D011134:Polysaccharides / Q000737:chemistry*; D013057:Spectrum Analysis; D014990:Xylans
D001704:Biopolymers; D052578:Ionic Liquids; D008299:Maleic Anhydrides; D011134:Polysaccharides; D014990:Xylans; C007916:hemicellulose