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