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Abstract
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In this study, GO/ZnFe2O4/NiO nanocomposites (NCs) were successfully synthesized via two-step hummer, hydrothermal
and calcination methods, consecutively. These nanocomposites were used as fillers to synthesis radar absorbing polyurethane
(PU) foams. The prepared nanocomposites and foams were characterized by X-ray diffractometer, FTIR spectrometer,
scanning electron microscope, X-ray fluorescence spectrometer, thermogravimetric and derivative thermogravimetric
(TGA–DTG) analyses, and vibrating sample magnetometer. PU foams were prepared at 5 mm thickness and the effects of
diisocyanate and polyol role on dispersing of fillers, the total weight ratio of fillers in the polymeric nanocomposite, and
the amount of dielectric, magnetic, and conductive components on radar absorbing properties were investigated. To study
radar absorbing properties, a vector network analyzer was applied to measure the scattering parameters. By analyzing radar
absorbing properties, one of the PU foams had the area under the curve of reflection loss equals to 184.667 GHz.dB in the
X-band frequency range (8–12 GHz). This foam with 5 mm thickness containing the GO/ZnFe2O4/NiO NC with the weight
ratio of components equal to 25%, 21%, and 52%, respectively, and the total weight ratio of the NC in the foam equal to 9%,
was dissolved in diisocyanate. All the prepared foams had reflection loss values less than − 30 dB equals to 99.9% absorption
over the X-band frequency range.
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