Light weight and flexible poly(ether ether ketone) based composite film with excellent thermal stability and mechanical properties for wide-band electromagnetic interference shielding.

This study proposes an efficient method for fabricating a light weight and flexible composite film with excellent thermal stability and mechanical properties for wide-band electromagnetic interference (EMI) shielding, which was prepared by melt blending and subsequent melt extrusion using poly(ether ether ketone) (PEEK) as a matrix, multi-walled carbon nanotube wrapped poly(ether sulfone) (wrapped MWCNTs) as a conductive filler, and GENIOPLAST® PELLET S (GPPS, high-temperature lubricant) as a processing aid. GPPS was firstly used in EMI application, to reduce the melt viscosity of PEEK as well as to improve the dispersion of wrapped MWCNTs, which enables it to fabricate a highly efficient EMI shielding (∼74.6 dB mm) PEEK/wrapped MWCNT/GPPS1.0 composite film with a thickness of 180 μm. Furthermore, the lightweight composite film exhibits high thermal stability ( degradation temperature at 5% mass loss of 586 °C) and good mechanical properties (tensile strength of 101 MPa), being superior to other previously reported EMI shielding films. The above mentioned enhanced property demonstrated its potential application as a high performance EMI shield for certain applications such as in the aerospace, weapons, and microelectronics industries, which require materials exhibits EMI shielding as well as superior mechanical properties and thermal stability.