短切碳纤维表面处理对木粉/高密度聚乙烯复合材料性能的影响

木粉（WF）填充增强高密度聚乙烯（HDPE）复合材料具有良好的环境效益，少量引入短切碳纤维（SCF）可进一步提高其力学性能。为改善SCF与WF/HDPE复合材料中塑料基体的界面结合，提高SCF在WF/HDPE复合材料中的增强作用，采用气相、液相及气液双效氧化3种表面处理方式处理SCF，通过挤出工艺制备短切碳纤维增强木粉/高密度聚乙烯复合材料（SCF-WF/HDPE），探讨了不同处理方法对SCF-WF/HDPE复合材料性能的影响。SEM观察显示，表面处理增大了SCF的表面粗糙度，可提高其与基体的界面结合；动态力学性能分析证实碳纤维提高了存储模量。测试结果表明：表面处理过的短切碳纤维可使SCF-WF/HDPE复合材料的力学性能、热力学性能和蠕变性能均得到显著提高，其中气相表面处理的效果最好。对比WF/HDPE复合材料，SCF-WF/HDPE的拉伸强度提高了34.5%，弯曲强度提高了23%，冲击强度提高了54.7%。

Effect of surface treatment of short carbon fibers on the properties of wood flour/high density polyethylene composite

Wood flour/high density polyethylene (WF/HDPE) composite provides environmental benefit. To improve WF/HDPE properties, the short carbon fibers (SCF) were introduced to WF/HDPE and short carbon fiber reinforced wood flour/high density polyethylene composite (SCF-WF/HDPE) was prepared. The surfaces of SCF were treated by three methods, including gas-phase, liquid-phase and gas-liquid dual-phase oxidization, to enhance the interface bonding between short carbon fibers and plastic matrix. Then the short carbon fiber-wood flour/high density polyethylene (SCF-WF/HDPE) composites were prepared by extrusion process. The mechanical, dynamic mechanical and rheological properties were measured to evaluate the effectiveness of the treatment methods. SEM shows that the surface roughness of carbon fibers increases after the surface treatment, which enhances the interfacial bonding with HDPE matrix; The DMA reveals the storage modulus increases. The results demonstrate that the surface treatment significantly improves the mechanical properties, thermal dynamic property and creep performance of WF/HDPE composite. The best surface treatment method is gas-phase treatment. Comparing with the WF/HDPE composite without carbon fibers, the composite containing gas-phase treat carbon fibers increases in tensile strength by 34.5%, flexural strength by 23%, and impact strength by 54.7%.