High performance microwave shielding in green nanocomposite coating based on polyurethane via nickel oxide, Mn_xFe_(3-x)O_4 and polyaniline nanoparticles

摘要

This study deals with the preparation of a green nanocomposite coating based on polyurethane containing nickel oxide, Mn_xFe_(3-x)O_4 (x = 0.5, 1, and 1.5) and polyaniline nanoparticles for electromagnetic wave absorption. Polyurethane nanocomposites were successfully synthesized from a vegetable polyol based on epoxidized soybean oil and methylene diphenyl diisocyanate (MDI). X-ray diffractometer (XRD), scanning electron microscope, (SEM) and energy dispersive X-ray spectrometer (EDS), were utilized to the characterization of the phase structures, morphologies, particle size and chemical composition of the compounds, respectively. A vector network analyzer (VNA) in X-band frequency range was used to study microwave absorbing properties of the prepared nanocomposite. Besides, Taguchi method was utilized to investigate the effect of factors, including the weight ratios of nickel oxide, Mn_xFe_(3-x)O_4, and polyaniline to the total weight of the sample and the content of X in Mn_xFe_(3-x)O_4 on the microwave absorbing properties. Finally, the optimal sample was synthesized under determined conditions by Taguchi method. The results exhibited that the optimal sample has reflection loss less than -30 dB corresponding to 99.9% absorption across the X-band frequency range (8-12 GHz).