【目的】建立一种室温均相改性农林废弃物的方法．【方法】选用甘蔗渣为原料，在室温下，将其溶解在二甲基亚砜/1-甲基咪唑溶剂体系中，利用异丁酸酐为改性剂，对甘蔗渣进行了均相改性研究．【结果和结论】保持反应时间为180 min，将酸酐与甘蔗渣质量比从1∶1提高到6∶1时，甘蔗渣均相衍生化的反应得率由10.3％增加到49.2％；保持酸酐与甘蔗渣质量比为3∶1，将反应时间由15 min提高到45 min，反应得率由25.1％增加到27.4％，但进一步延长反应时间，反应得率略有下降，反应时间240 min时，反应得率降低至24.7％．利用FT-IR和CP/MAS 13 C-NMR分析发现，甘蔗渣与异丁酸酐发生了酯化反应，在甘蔗渣中引入了带有烷基的酯键基团．甘蔗渣中的碳水化合物和木质素分子均参与了化学反应．%Objective] A new method for homogeneous modification of agricultural and forest residues at room temperature was proposed .[Method] Homogeneous derivatization of sugarcane bagasse with isobu-tyric anhydride in the dimethyl sulfoxide/1-methylimidazole ( DMSO/NMI) solvent system was investiga-ted at room temperature in the present study .[Result and conclusion] Holding reaction time for 180 min, the mass percent gain ( WPG) of sugarcane bagasse increased from 10.3%to 49.2%with the increment of the mass ratio of isobutyric anhydride to ball-milled sugarcane bagasse from 1∶1 to 6∶1.The increase of reaction time from 15 min to 45 min resulted in an enhancement of WPG from 25.1% to 27.4%, keeping the mass ratio of isobutyric anhydride to ball-milled sugarcane bagasse at 3∶1.However, further improvement of reaction time led to a decrease in WPG , and the WPG decreased to 24.7% within 240 min under the given conditions .FT-IR and CP/MAS 13 C-NMR analyses indicated that the esterification between sugarcane bagasse and isobutyric anhydride did occur at room temperature in DMSO /NMI.The esterification of carbohydrates and lignin with isobutyric anhydride were both confirmed .
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