蔗渣纤维表面处理方法对蔗渣纤维/聚乳酸复合材料力学性能的影响

采用了硅烷偶联剂结合碱溶液处理的方法对蔗渣纤维(BF)进行了表面改性, 研究了不同表面处理方法对蔗渣纤维/聚乳酸(PLA)复合材料力学性能的影响, 用SEM对BF处理前后的形貌及复合材料的冲击断面进行了观察。结果表明: 经表面改性的BF都不同程度地改善了BF与PLA基体之间的界面相容性, 其中碱处理后再经偶联剂处理的方法效果最佳, 在40%(质量分数)蔗渣纤维的高填充量下, 复合材料的拉伸强度和冲击强度分别为纯PLA的85.42%和59.74%, 较好地保持了基体PLA的力学强度; 碱处理使BF表面变粗糙、 长径比增大、 比表面积增加, 与PLA的界面粘结加强, 从而有效地提高了BF/PLA复合材料的力学性能。

Effect of surface treatment on the mechanical properties of BF/PLA composite

The silane coupling agent and alkaline solution were used for surface treatment on the bagasse fiber (BF), and the influence of surface treatment methods on the mechanical property of BF/PLA composite were investigated. The morphology of the impact section of BF/PLA composite was observed by SEM. The results show that surface treatment on BF can improve the interface compatibility between BF and PLA matrix and enhance the mechanical strength of BF/PLA composite to some extent. Among the three surface treatments investigated, the silane coupling agent treatment after being treated by alkaline solution on BF performs the best effect on improving the mechanical property of BF/PLA composite, and the mechanical strength of BF/PLA composite can keep 85.42% tensile strength and 59.74% impact strength of neat PLA after treated by alkaline solution combined with silane coupling agent even the mass fraction of BF reaches 40%. Moreover, the surface of BF turns rough, specific surface area grows larger, length-diameter ratio increases and the interfacial adhesion enhances after being treated by alkaline, which result in the effective improvement of the machanical property.