Preparation And Absorbing Properties Of FeSiCr/Polyaniline Composites

With the progress and development of science and technology,various electronic devices are increasing day by day,and the electromagnetic wave radiation generated by them has become a new social pollution because they are invisible and untouchable and can not smell.Electromagnetic wave radiation not only threatens the physical and mental health of the human body,but also prevents electronic devices from functioning properly.Therefore,the research of absorbing materials is of great significance.Composite materials with both magnetic and electrical losses can be prepared by combining iron silicon-chromium magnetic powder with conductive polymer,which can effectively improve the problems of large density and single loss mechanism of iron-silicon-chromium magnetic powder,which makes the absorption Wave performance has been effectively improved.In this paper,FeSiCr/PANI composite was prepared by in-situ polymerization of aniline monomer on the surface of Fe SiCr with FeSiCr magnetic powder as matrix.The materials were characterized by X-ray diffractometer,Fourier infrared spectrometer,scanning electron microscope and four-probe tester.The influence of An content and magnetic field on the absorbing property of the composite material and the modification mechanism of FeSiCr magnetic powder surface were discussed.The results showed that:(1)The surface modification was used on FeSiCr magnetic flake with Tetraethyl Orthosilicate and silane coupling agent,and-OH and-NH2 were introduced into the surface of FeSiCr magnetic powder through the hydrolysis and condensation reactions of the modifier,which can effectively improve the interface binding ability of FeSiCr magnetic powder and polyaniline,and is conducive to improving the absorption performance.(2)The minimum reflectivity of FeSiCr/PANI composite material shifts to high frequency with the increase of An content.When the addition amount of An is 2.50 g,the maximum absorption peak of TEOS-Fe SiCr/PANI composite material at 5.3 GHz is-19.39 dB,and the frequency bandwidth with reflectance less than-10 dB is about 1.6GHz.When the addition amount of An is 0.89 g,the minimum reflectivity ofKH550-FeSiCr/PANI composite material is-15.7 dB,and the reflectivity is less than-10 dB,which is about 1.52 GHz.(3)The polyaniline prepared under magnetic field is more regular in structure and smaller in particle size,and the morphology of the composite material also changes under magnetic field due to orientation action.The minimum reflectivity of Fe SiCr/PANI composite material shifts to low frequency with the increase of magnetic field strength.When the magnetic field is 92 mT,the minimum reflection of the Fe SiCr/PANI-92 mT composite material can reach-15.9 dB at 4.81 GHz,and the frequency bandwidth of less than-10 dB is about 1.92 GHz.