Enriching Carbon Nanotubes in Poly (Arylene Ether Nitrile) Porous Films for Enhanced Electromagnetic Shielding Properties
Abstract
The microstructure of the composite materials and the content of conductive fillers play a decisive role in the electromagnetic shielding performance. Herein, by leveraging the dispersing effect of polyvinylpyrrolidone (PVP K30) and its interaction with carbon nanotubes (CNTs), porous films with uniformly enriched CNTs at the pore interface are fabricated, resulting in a conductive three-dimensional network structure. By controlling the mass ratio of PVP K30 to CNTs, the honeycomb pore morphology is adjusted while avoiding high-content CNTs agglomeration. This results in a uniform enrichment of CNTs at the interface of porous films, reducing the CNTs content required to construct a continuous conductive network. The synergistic effect of the uniform CNTs enrichment at the porous films interface and the honeycomb pore structure promotes multiple reflections and absorptions of incident electromagnetic waves. The porous films with enriched CNTs at the interface exhibit a total shielding performance of 26.5 dB at 8.2 GHz, with an absorption loss of 23.6 dB. It also achieves a high tensile strength of 9.6 MPa and an elongation at break of 104%. This study provides a new approach for effectively controlling honeycomb pore size while uniformly dispersing CNTs.