In-situ growth of polypyrrole on aramid nanofibers for electromagnetic interference shielding films with high stability

Flexible electromagnetic interference (EMI) shielding films with high stability have shown promising prospect in harsh working conditions such as military, communication, and special protection fields. Herein, flexible aramid nanofibers@polypyrrole (ANF@PPy) films with high stability were easily achieved by the in-situ growth of PPy on the surface of ANF and the subsequent pressured-filtration film-forming process. When the amount of pyrrole (Py) monomer is 40 µL, the ANF@PPy (AP40) film exhibited excellent EMI shielding performance with shielding effectiveness (SE) of 41.69 dB, tensile strength of 96.01 MPa, and fracture strain of 21.95% at the thickness of 75.76 µm. Particularly, the anticipated EMI shielding performance can be maintained even after being heated at 200 °C in air, soaked in 3.5% NaCl solution, repeated folding for one million times, or burned directly, indicating superior environmental durability in harsh conditions. Therefore, it is believed that the ANF@PPy films with high stability offer a facile solution for practical protection for high-performance EMI shielding applications.