Three dimension phenolic resin derived carbon-CNTs hybrid foam for fire retardant and effective electromagnetic interference shielding

Three dimension fire retardant carbon-CNTs hybrid foams for electromagnetic interference (EMI) shielding effectiveness (SE) were fabricated using a polyurethane (PU) template. Phenolic resin with different contents (0.2–2 wt.%) of mutltiwalled carbon nanotubes (MWCNTs) was mixed using a magnetic stirrer for making a homogenous slurry and then PU foam was impregnated in this slurry followed by carbonization at 1000 °C. The foams were characterized for their morphological, structural, mechanical, EMI shielding, and fire-retardant properties. The total EMI shielding effectiveness (SE) of -57.2 dB was achieved for the carbon foam containing 1 wt.% MWCNTs in the frequency range of 8.2–12.4 GHz. Moreover, the addition of MWCNTs into phenolic resin also enhanced the compressive strength (6.5 MPa), thermal stability and fire retardant performance of carbon-CNTs hybrid foams. The multifunctional carbon-CNTs hybrid foams demonstrate that they are outstanding materials with potential applications in EMI shielding and thermal management for defense and aerospace sectors.