摘要
木质素作为自然界含量仅次于纤维素的生物质聚合物,有效利用率尚不到2%,因此对木质素的综合利用具有重要意义。分别将未改性木质素和不同化学改性处理(马来酸酐相容剂MAPE、聚四氟乙烯PTFE、尿素Ur)的木质素进行球磨,同时将球磨后未改性木质素进行冷冻-干燥(FD)处理,然后与高密度聚乙烯(HDPE)复合熔融挤出,研究了不同改性处理木质素对HDPE/木质素复合材料的力学性能、热性能和流变性能的影响。结果表明,相比较未处理木质素的复合材料,MAPE、PTFE、Ur和FD处理的木质素/HDPE复合材料的拉伸强度分别提高了9. 45%、10. 55%、14. 06%和25. 17%。热性能分析结果表明,不同处理木质素的加入均不同程度地抑制了HDPE的结晶行为,其中尿素改性的复合材料的结晶度仅为16. 25%。FD和MAPE处理后的木质素/HDPE复合材料的黏度较未处理前有所降低。SEM图片显示改性处理后的木质素较未改性的木质素在塑料基体中具有更好的分散性。
Lignin is the second most abundant biomass in nature,which is only less than cellulose,however,its effective utilization ratio is less than 2%. Hence the comprehensive utilization of lignin has great significance. In this paper,the unmodified lignin and the chemically modified lignins( treated with maleic anhydride grafted polyethylene, polytetrafluoroethylene and urea) were ball-milled, and the unmodified lignin after balling was subjected to freeze-drying( FD) treatment. Then the lignin/high-density polyethylene( HDPE) composites were prepared by melt-extrusion. The effects of modified lignins on the mechanical,thermal and rheological properties of HDPE/lignin composites were investigated. The results show that the tensile strength of the lignin/HDPE composites treated with MAPE,PTFE,Ur and FD is higher than the unmodified by 9. 45%,10. 55%,14. 06% and 25. 17%,respectively. The thermal analysis indicates that the crystallinity of the HDPE is inhibited by the addition of lignin and the crystallinity of the composites modified by urea is only 16. 25%. The viscosity of the lignin/HDPE composites treated with FD and MAPE is lower than the untreated. In addition,the SEM images show that the modified lignins have better dispersion in the plastic matrix than the unmodified lignin..
作者
蒋敏
梅长彤
刘朝政
JIANG Min;MEI Chang-tong;LIU Chao-zheng(College of Material Science and Engineering,Nanjing Forestry University,Nanjing 210037,China)
出处
《塑料工业》
CAS
CSCD
北大核心
2019年第4期118-122,126,共6页
China Plastics Industry
关键词
木质素
改性
高密度聚乙烯
复合材料
力学性能
流变性能
Lignin
Modified
High Density Polyethylene
Composites
Mechanical Properties
Rheological Analysis
