【摘要】 以玉米芯木质素为原料，通过超声波辅助解聚制备了木质素低聚物，研究解聚条件对木质素低聚物产率及相对分子质量的影响，并以凝胶渗透色谱（GPC）、红外光谱（FT-IR）、二维核磁共振谱（2D-HSQC NMR）与核磁共振磷谱(³¹P NMR)表征木质素低聚物。研究结果表明：较优条件为在甲醇/水（4∶1,体积比）作溶剂体系，木质素与溶剂固液比200∶1（g∶L）,超声波（频率40 kHz,功率240 W）处理3 h。此条件下制备的木质素低聚物的产率达到40.2%,所得木质素低聚物的数均相对分子质量（M_n）为710,多分散指数（PDI）为1.62,保留了木质素的主要分子结构单元，同时其含总羟基10.49 mmol/g。更多还原

【Abstract】 Lignin oligomers were prepared by ultrasonic-assisted depolymerization using corn cob lignin as raw material. The effects of depolymerization conditions on the yield and relative molecular mass of lignin oligomers were investigated, and the lignin oligomers were characterized by gel permeation chromatography（GPC）, infrared spectroscopy（FT-IR）, two-dimensional nuclear magnetic resonance spectroscopy（2D-HSQC NMR） and nuclear magnetic resonance phosphorus spectroscopy(³¹P NMR). The results showed that the yield of resultant lignin oligomer reached 40.2% and the number-average molecular weight（M_n） of obtained lignin oligomer was 710 under the conditions of ultrasonic treatment（frequency 40 kHz, power 240 W） for 3 h and the solid-liquid ratio of lignin to solvent 200 ∶1（g ∶L） in methanol/water（4 ∶1, v ∶v） solvent system. The polydispersity index（PDI） was 1.62, which reserved the main molecular structure units of lignin, and the total hydroxyl content was 10.49 mmol/g.更多还原