Porous fibres of a polymer blend for broadband microwave absorption

Abstract

This study is on the advantages of introducing pores in polymer blend fibres in broadband microwave absorption. The electrospun porous and non-porous fibres of a blend, polyvinyl butyral and poly(3,4-ethylenedioxythiophene)polystyrene sulfonate-PEDOT:PSS (PPPS), are explored. The porous PPPS fibres (PPPS-f) demonstrated an outstanding reflection loss (RL) bandwidth (8.2–12.4 GHz, X-band) with a minimum RL of −23 dB, whereas the non-porous PPPS-f of the same thickness did not exhibit even adequate levels of RL. A high dielectric loss tangent and the electromagnetic attenuation constant (with a phase constant) are the major factors contributing to this difference. Additionally, impedance matching and the electromagnetic energy density are observed to be the major factors in porous PPPS-f achieving this excellent microwave absorption bandwidth, a finding supported by microwave simulation data. A bi-layer structure of porous PPPS-f and non-porous PPPS-f is also proposed to achieve an X-band absorption bandwidth at minimum thickness. An android mobile app is also developed to identify the RL of single and bi-layered porous PPPS-f and non-porous PPPS-f conveniently.