1.石油天然气精细化工教育部和自治区重点实验室 新疆大学化工学院，新疆 乌鲁木齐 830046;2.新疆大学
为减缓废弃棉秆造成的环境压力，提高棉秆副产物综合利用，本文采用乙二醇溶剂分离棉秆中的木质素，研究了各种因素对其分离效果的影响，并分析提取物的各项性能及其对PP抗氧能力的影响。结果表明，在160℃下用0.8 mol·L-1的乙二醇溶液对棉秆处理1h可达到最高产率84.58%；木质素改性对PP的结晶性能以及熔融和结晶温度影响不大，但是对其氧化诱导时间、流变性能和力学性能产生影响：当在PP中添加0.5wt%的木质素，氧化诱导时间相较纯PP试样提高38.3%，微量混合流变测试中剪切扭矩提高了25.58%，断裂伸长率降低9.34 %、冲击强度无变化。说明乙二醇法提取的木质素在PP中能够有效发挥抗氧化效果。
To alleviate the environmental pressure caused by waste cotton straw and improve the utilization of cotton straw by-products, this paper used ethylene glycol solvent to separate lignin from cotton straw, the effects of various factors on its separation effect were studied, and the properties of the extract and its effect on the antioxidant capacity of PP were analyzed. The results show that the highest yield of 84.58% could be achieved by treating cotton straw with 0.8 mol?L-1 ethylene glycol solution for 1h at 160℃. The lignin modification has little effect on the crystallization properties and melting and crystallization temperatures of PP, but has an effect on its oxidation induction time, rheological properties, and mechanical properties: when 0.5wt% of lignin is added to PP, the oxidation induction time is increased by 38.3% compared with that of pure PP specimens, the shear torque is 25.58% higher in micro mixing rheological test, the elongation at break is 9.34% lower, and the impact strength has no change. It indicates that the lignin extracted by the ethylene glycol method can effectively exert an antioxidant effect in PP.