碳纳米管含量对碳纳米管/聚丙烯复合材料性能及微结构制品的影响

Effect of CNTs Content on the Properties of CNTs/PP Composites and Microstructured Products

采用稀释母料的熔融共混方式制备碳纳米管/聚丙烯复合材料(CNTs/PP)并加工出微结构面板。研究不同含量CNTs的复合材料的结晶行为、力学性能以及流变性能,得到CNTs对聚合物的增强机理,开拓CNTs复合材料在微结构制品方面的应用。结果表明:采用稀释母粒的方式,CNTs在PP基体中分散相对均匀;CNTs的加入会抑制β晶的形成,降低在(040)晶面取向度;同时也会使复合材料的结晶度从60.36%降低到53.17%。随着CNTs含量的增加,CNTs/PP复合材料的弹性模量可以提高近43%,拉伸强度可以提高近26%。CNTs含量为1wt%时,其冲击强度最高。在低剪切速率下CNTs能显著提高复数粘度,剪切速率越高,复数黏度对CNTs含量的依赖性越低。在纯PP中添加CNTs后,剪切应力明显提高,且随剪切速率的增大呈同步变化趋势。综合结果分析,选择CNTs含量低于3%进行微结构加工较为适宜。

CNTs/PP composites were prepared by melt blending of diluted masterbatch and microstructured panels were processed.The crystallization behavior,mechanical and rheological properties of composites with different CNTs contents were studied.The enhancement mechanism of CNTs on the polymer is obtained,which can improve the application of CNTs composites in microstructured products.The results show that the CNTs are relatively uniformly dispersed in the PP matrix by diluting the masterbatch.The addition of CNTs inhibits the formation ofβcrystals and reduces the degree of orientation at(040)crystal plane.It also reduces the crystallinity of the composite,from 60.36%to 53.17%.Besides,with the increase of CNTs content,the modulus of elasticity can be increased by nearly 43%and the tensile strength can be increased by about 26%.The impact strength reaches the highest when the CNTs content is 1 wt%.Moreover,the complex viscosity is increased significantly by CNTs at low shear rates and the higher shear rate,the lower dependence of complex viscosity on CNTs content.The shear stress increases significantly and shows a trend of simultaneous change when CNTs are added to pure PP.At last,the synthesis result shows that it is preferable to select less than 3%CNTs for microstructure processing.