Composition dependent microwave properties of dielectric-conductor nanocomposites.

Broadband dielectric spectra of dielectric-conductor nanocomposites of poly(ethylene terephthalate) with multiwalled carbon nanotubes (PET-xCNT) were used for calculation of their free-space shielding and absorbing parameters in the frequency range from 1 MHz to 1 THz. Revealed correlation of the composition and frequency dependent microwave dielectric and shielding/absorbing parameters allows determination of the CNT concentration range optimized for the shielding (x ≥ 0.4 vol%) and absorption (0.12 < x < 0.6 vol%) applications. Broadband (two frequency decades) 40 dB shielding, narrowband 30÷40 dB absorption and high attenuation constant up to 104 neper/m were demonstrated. [ABSTRACT FROM AUTHOR]