长径比对HDPE/MWCNTs复合材料性能的影响

摘要

以高密度聚乙烯(HDPE)为基体、不同长径比多壁碳纳米管(MWCNTs)为填料,研究长径比对 HDPE/MWCNTs复合材料的导电和导热性能的影响。结果表明：填充不同长径比的 MWCNTs,复合材料的阈值填充量是不同的。长径比越大,阈值填充量越小。相对于导热曲线,导电曲线中出现了渗流阈值,这在一定程度上说明了隧道效应对体系的导电性能有很大的提高。通过扫描电子显微镜照片从微观上解释不同长径比对复合材料性能的影响,并进一步分析长径比最短却性能优异的原因。%The influences of slenderness ratio on the electrical conductivity and thermal con-ductivity of high-density polyethylene(HDPE)/multi-walled carbon nanotubes (MWCNTs ) com-posites were studied with HDPE as matrix and MWCNTs with different slenderness ratios as fillers.The results show that the different slenderness ratios of the filled MWCNTs lead to the differences in the threshold filling quantity of the composites. The larger the slenderness ratio is,the smaller the threshold filling quantity is.Referring to the similarity between the thermal and electrical conductivity,the percolation threshold is not found in the thermal curve,which indicates that the tunneling effect can obviously improve the electrical conductivity of the system to a certain degree. The SEM images show the significance of different slenderness ratios on properties of composites from the microscope, and further explain the reason that the smaller the slenderness ratio is,the better the property is.