ABS/CNTs/Fe3O4复合材料及其双峰泡沫的电磁屏蔽性能研究OA北大核心CSTPCD

In this study,acrylonitrile-butadiene-styrene(ABS)/carbon nanotubes(CNTs)/ferriferous oxide(Fe3O4)composite and its bimodal foams with excellent conductivity and electromagnetic interference shielding(EMI SE)were prepared by melt blending and supercritical carbon dioxide foaming technique,respectively.The effects of the mixture ra-tio and content of the two fillers on the foaming properties,electrical conductivity,dielectric properties and EMI SE of ABS composites and bimodal foams were studied.The experimental results indicated that the average cell size of ABS bimodal foams decreased with the gradual increase of CNTs and Fe3O4 contents,the average large cell size descended from 283.54 μm to 70.79 μm,and the average small cell size declined from 11.89 μm to 7.19 μm.While the cell densi-ty of large cells in ABS bimodal foams went from 2.88×104 cell/cm3 to 2.51×106 cell/cm3 and the cell density of small cells increased from 2.18×108 cell/cm3 to 1.12×109 cell/cm3.The electrical conductivity of ABS composites boosted from 0.304 1 S/cm to 1.360 8 S/cm,and the total EMI SE increased from 28.65 dB to 43.05 dB with the gradual in-crease of CNTs and Fe3O4 contents.After foaming,the electrical conductivity of ABS bimodal foams augmented from 0.002 7 S/cm to 0.065 4 S/cm,and the total EMI SE increased from 10.89 dB to 21.08 dB.The maximum specific electromagnetic shielding effectiveness of ABS composite and its bimodal foams was 41.33 dB/(g·cm-3).