木质素在三氮唑基离子液体中溶解性能的研究

摘要

Three triazolyl ionic liquids, i.e., 1-butyl-3-methylimidazolium triazole([Bmim]tr), N-methyl-N-n-butylmorpholinium triazole([Bmmo]tr), N-n-butylpyridinium triazole([Bpy]tr), were synthesized.It was found that ionic liquid[Bmim]tr had good solubility performance for lignin dissolution,and the solubility was 58.61 g at 55 ℃ under microwave heating.The chemical structure, molecular weight, crystalline and morphology of regenerated lignin from microwave treatment were characterized by HSQC, FT-IR, GPC, XRD and SEM.The results indicated that microwave heating trends to cleavage hydrogen bonds and β-O-4′ linkages, which accelerated the dissolution of lignin.And the basic structural unit of lignin was not destroyed in the dissolution process.The analysis showed that the dissolution mechanism of lignin in ionic liquid was the hydrogen bond damage and fracture of β-O-4′ connection structure.%设计合成并表征了3种三氮唑基离子液体: 1-丁基-3-甲基咪唑三氮唑盐([Bmim]tr)、N-甲基-N-丁基吗啉三氮唑盐([Bmmo]tr)和N-丁基吡啶三氮唑盐([Bpy]tr),其中木质素在[Bmim]tr中的溶解性能最佳,在55 ℃的微波加热条件下,木质素溶解度达到58.61 g.采用HSQC、GPC、FT-IR和XRD等技术对[Bmim]tr溶解再生前后的木质素进行了表征,结果表明:在溶解过程中微波加热更有利于破坏木质素的氢键和β-O-4′结构,加速木质素的溶解,并导致木质素非晶态化,而其基本结构单元没有发生改变.分析表明:木质素在离子液体中的溶解机理是氢键的破坏与重组、 β-O-4′连接结构的断裂.