改性芳纶纤维增强木粉/高密度聚乙烯复合材料的力学性能

采用螺杆挤出机研究了添加连续芳纶纤维增强木粉/高密度聚乙烯（CAF-WF/HDPE）复合材料，为改善CAF与WF/HDPE复合材料界面相容性，分别采用磷酸和硅烷偶联剂处理纤维。对比表面处理前后的CAF形态分析显示，经过处理的CAF表面粗糙度增加；采用磷酸和硅烷偶联剂处理，纤维束从基体中的拔出强度分别提高了94.9%和77.6%，表明处理后的CAF与WF/HDPE复合材料的界面结合强度有所提高。对比WF/HDPE复合材料，在挤出成型过程中加入未处理CAF，CAF-WF/HDPE复合材料拉伸强度、弯曲强度和冲击强度分别提高了32.1%、35.1%、515.1%；CAF采用硅烷偶联剂处理后，CAF-WF/HDPE复合材料对应的力学性能分别提高了42.0%、37.4%、550.2%。动态力学分析表明:表面处理后CAF与WF/HDPE复合材料的界面相容性得到改善。 

Mechanical properties of modified aramid fiber reinforced wood flour/high density polyethylene composites

The continuous aramid fiber(CAF) was added to wood flour/high density polyethylene(WF/HDPE) composites by screw extruder. Surface treatment of CAF with phosphoric acid and silane coupling agent was used to improve the interfacial compatibility between CAF and the WF/HDPE composites. The morphological analysis showed that the surface roughness of CAF increased after the surface treatment. Either the treatment of CAF with phosphoric acid or silane coupling agent, the pull-out strength of CAF bundle increases up to 94.9% and 77.6%, respectively. It shows that the interfacial bonding strength of the treated CAF and the WF/HDPE composites is enhanced. Compared with WF/HDPE composite without CAF, the composite with the untreated CAF results in that the tensile strength, flexural strength and impact strength of CAF-WF/HDPE composite increases by 32.1%, 35.1% and 515.1%, respectively. After CAF treated with silane coupling agent, the mechanical properties of CAF-WF/HDPE composite increase by 42.0%, 37.4% and 550.2%. The dynamic mechanical analysis shows that the interfacial compatibility of the CAF and WF/HDPE composite is improved after surface treatment.