Poly aryletherketone chemically modified multi-walled carbon nanotubes/poly etheretherketone electromagnetic interference shielding foam suitable for high temperature and strong corrosive media

Poly aryletherketone chemically modified multi-walled carbon nanotubes/poly etheretherketone (PAEK-m-CNTs/PEEK) electromagnetic interference (EMI) shielding foams were fabricated using supercritical carbon dioxide (Sc-CO₂) foaming technique saturated near-melting point (T_m). The percolation thresholds for conductivity and EMI shielding of PAEK-m-CNTs/PEEK foams were both significantly reduced by the presence of the porous structure, reaching to 0.0457 vol% and 0.123 vol%, respectively. These reductions were observed to be 87.72 % and 75.20 % of those of PAEK-m-CNTs/PEEK composites. This could be attributed to the heterogeneous nucleation of PAEK-m-CNTs, which are uniformly dispersed in PEEK, in addition to the Sc-CO₂ foaming technique saturated near T_m. By comparison, it could be observed that the specific total electromagnetic shield effectiveness (SSE_Total) of PAEK-m-CNTs/PEEK foam with a filler content of 0.440 vol% was 687.9 % higher than that of PAEK-m-CNTs/PEEK composite with a filler content of 0.496 vol%. Moreover, the introduction of the porous structure transformed the electromagnetic shielding material from reflective to absorptive. In addition, PAEK-m-CNTs/PEEK foams demonstrated the capacity to maintain stable performance even in high temperatures of up to 315 °C and in the presence of strong corrosive media.