Electromagnetic
radiation pollution poses significant
threats to
both electronic equipment functionality and human health, necessitating
the advancement of electromagnetic shielding materials. Among them,
electromagnetic shielding nonwoven fabrics offer notable advantages,
such as lightweight, affordability, simplicity in production, and
versatility in application. This study focuses on utilizing polyester
fiber (PET) as the base material, surface-modified with polyethylenimine
(PEI), and impregnated with nanocarbon material slurry. Subsequently,
electromagnetic shielding nonwoven fabrics are fabricated via a hot-pressing
process. The micromorphology and electromagnetic shielding performance
of the resulting fabrics were characterized through SEM observation
and vector network analyzer measurement. Results demonstrate that
employing a mixed solution of carbon nanotubes (CNTs), graphene (Gr),
and polypyrrole (PPy) in a mass ratio of 6:1, alongside hot pressing
at 240 °C with three layers, yields polyester fiber-based nonwoven
fabrics with exceptional electromagnetic shielding effectiveness,
achieving a shielding coefficient of up to 65 dB. Meanwhile, polyester
nonwoven fabrics showed significant flame retardancy and prolonged
burning time after impregnation with electromagnetic shielding materials,
and the burning time of PET nonwoven fabric impregnated with CNTs/Gr/PPy
was prolonged to 61 s. This research underscores the electromagnetic
shielding prowess of polyester fiber-based nonwoven fabrics and their
wide-ranging applications in electrical circuit protection, military
equipment, and beyond, and offers insights for their large-scale production.