碳纳米管纸基复合材料的制备及电磁屏蔽性能研究

Research of Preparation and EMI Shielding Properties of Carbon Nanotube Paper-based Composite Materials

本研究以间位芳纶纤维、浆粕为基体,单壁碳纳米管(SWNT)和多壁碳纳米管(MWNT)为填料,采用造纸湿法成形技术,制备了间位芳纶/单壁碳纳米管纸基复合材料(SP)和间位芳纶/多壁碳纳米管纸基复合材料(MP)。探讨了碳纳米管含量和种类对碳纳米管纸基复合材料导电性能、介电性能、电磁屏蔽效能的影响,并分析了碳纳米管纸基复合材料与电磁波的相互作用。结果表明,SP的表面电导率和体积电导率的逾渗阈值均为0.16%,MP的表面和体积电导率的逾渗阈值分别为0.37%和0.93%。碳纳米管含量相同时,SP比MP具有更高的电导率、介电常数实部、介电损耗和电磁波吸收率,其中SP在8~12 GHz的频率下(厚度0.15 mm)具有27 dB的电磁屏蔽效能。

In this study,two kinds of paper-based composite materials,single-walled carbon nanotube paper(SP)and multi-walled carbon nanotube paper(MP)were prepared by wet forming method,using meta-aramid fiber and pulp as matrix,and single-walled carbon nanotube(SWNT)and multi-walled carbon nanotube(MWNT)as fillers.The effects of carbon nanotube content and type on the conductive proper⁃ties,dielectric properties,EMI shielding properties of the carbon nanotube paper-based composite materials were investigated,and their in⁃teractions with electromagnetic waves were analysed.The results showed that the percolation thresholds of surface and volume conductivity were both 0.16%for SP,and 0.37%and 0.93%for MP,respectively.For the same carbon nanotube content,SP had higher conductivity,real part of dielectric constant,dielectric loss and electromagnetic wave absorption than MP,in which SP could have 27 dB EMI shielding properties at 8~12 GHz(thickness of 0.15 mm).