High strength and light weight polyamide 6/carbon fiber composite foams for electromagnetic interference shielding

In this study, high strength and light weight polyamide 6/carbon fiber (PA6/CF) composite foams were prepared by chemical injection foaming method. The foaming performance, electromagnetic interference (EMI) shielding efficiency total(SET), and mechanical properties of PA6/CF composite foams with different CF contents were investigated. The results show that the shear viscosity and strain hardening behavior obvious increased with the augment of CF content, which helped to PA6/CF composite foams to take the cell structure with smaller size, greater density, and more regular morphology. PA6/CF composite foam with cell size of 56.8 mu m, and cell density of 1.81 x 10(6) cells/cm(3) was achieved at 22 wt% CF. Meanwhile, PA6/CF composite foam had good EMI SET, at 22 wt% CF addition. The specific EMI SET of PA6/CF composite foam is 36.6 dB, 27.6% higher than that of solid 26.5 dB, the excellent cell structure helps to improve the EMI SET. In addition, PA6/CF composite foams also had excellent mechanical properties. Therefore, PA6/CF composite foams had broad application prospect in EMI shielding materials field, combining the advantages of simple preparation process, light weight and EMI shielding.