Research On The Anticorrosive And Microwave Absorbing Properties Of Polyaniline-based Composites

Due to its simple synthesis,strong structural design,good dielectric properties and low density,polyaniline has become a hot spot for electromagnetic absorption materials.By optimizing the electromagnetic parameters of polyaniline with reasonable design,a light-absorbing polyaniline absorption material can be prepared.Absorbers used as absorption coatings also have strong requirements for the corrosion protection of coatings.The addition of anti-corrosion fillers will affect the electromagnetic properties of absorbers,and thus affect the electromagnetic matching of the materials.Therefore,it is urgently needed to develop materials with both anti-corrosion and microwave absorption functions.Polyaniline is widely used in the field of anti-corrosion and microwave absorption.This article has studied the anti-corrosion and microwave absorption properties of the polyaniline based material,expected to obtain functional materials with both antisepsis and microwave absorption.(1)Synthesis and anti-corrosion properties of CNT/PANI composites:Interactions between aniline and carboxylated carbon nanotubes(CNTs)can be generated,and CNT/PANI(CP)composites were prepared by aniline oxidative polymerization on the surface of CNTs.Compared to PANI,the electrochemical activity of CP extends to neutral and alkaline.The effect of the doped organic acid type on the dispersion of CP in the polymer coating was studied.The results show that a small amount(0.1%)of CP can be coated to obtain antistatic properties,which is a 10-fold reduction compared to 1%required for CNTs to achieve antistatic.The corrosion resistance of composites were studied by electrochemical method,and its anti-corrosion performance was excellent.(2)Synthesis and microwave absorption properties of CNT/Fe3O4/PANI composites:Firstly,Fe3O4 was deposited on the CNT-COOH by co-precipitation method,and then PANI was coated in the surface of the binary composite material by in situ polymerization.The polymerization of aniline layer realizes the preparation of the ternary microwave absorption material.The structure and morphology of the polymer and its formation mechanism were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FITR).The synthesized nanocomposite material was filled with paraffin as a filler to prepare microwave absorption samples.The electromagnetic parameters were tested by the coaxial method.The differences of absorption properties in binary and ternary composites were discussed,and the reasons for influencing the microwave absorption properties were explored,and the influence factors were analyzed.Through the discussion of the electromagnetic parameters,the influence of the addition of Fe3O4 and polyaniline was studied,thus providing a theoretical basis for the preparation of microwave absorption materials.(3)Synthesis,anticorrosive and microwave absorption properties of ternary rGO/Fe3O4/PANI nanocomposites:The ternary rGO/Fe3O4/PANI(GMP)composites were designed and synthesized by a two-step method.Firstly,the rGO/Fe3O4(GM)binary composites were prepared by hydrothermal method.Then ternary GMP composites were prepared by in-situ aniline polymerization on the surface of GM.The structure and morphology of the composites were characterized by XRD,FTIR,UV-vis and TEM.The results showed that Fe3O4 supported rGO composites coated with polyaniline were successfully synthesized.Magnetic properties,redox activity and microwave absorption properties were characterized by VSM,CV,VNA.The magnetic properties of GMP composite exhibit superparamagnetic property with a saturation magnetization of 22.88 emu/g.The redox activity of GMP expanding to neutral environment is caused by the interfacial electron transport interaction.The microwave absorption performance of GMP is up to-28.2 dB at 14.4 GHz and the absorption bandwidths below-10 dB are 5.4 GHz(from 12.6 to 18 GHz)with a thickness of 2 mm.This can be attributed to its well-organized nanoscale morphology,which bringing the impedance matching of the individual components of GMP.