Study On The Preparation And Microwave Absorbing Properties Of MXene Based Silicone Rubber Foam

With the rapid development of electronic communication industry in modern society,the problem of electromagnetic radiation pollution is becoming more and more serious,so the development and application of high-performance absorbing materials tend to be urgent.However,some traditional absorbing materials have some shortcomings in absorption intensity,absorption bandwidth,thickness,density,durability and so on,and it is difficult to meet the application requirements of absorbing materials in wider fields.Therefore,it is necessary to develop new absorbing materials to achieve the technical goals of high absorption intensity,wide absorption band,thin thickness and light weight.MXene is a new two-dimensional(2D)lamilar material with excellent metal conductivity,hydrophilicity and structural designability.It is one of the most concerned 2D materials at present.The silicone rubber foams not only have the characteristics of silicone rubber itself,such as high elasticity,high and low temperature resistance,environmental protection and no toxicity,but also have porous structure,and low density,which are very suitable as wave absorption materials.Therefore,the combination of MXene and silicone rubber foam to prepare absorbing composites can have the advantages of both,and has a wide range of application prospects in the fields of electronic communications,new energy vehicles,national defense and military industry.The contents of this study include:Firstly,using Ti₃AlC₂ as the precursor and LiF-HCl as the mixed etching agent,MXene with different etching time of 24h,48h and 72h respectively was prepared to obtain different etching degrees.The MXene was characterized by SEM,XRD and XPS analysis.It was shown that the MXene etched for 48 h had superior absorbing performance.The minimum reflection loss(Rl_min)was-51.22 dB,and when the thickness was only 1.34 mm,the effective absorption bandwidth(EAB)was 3.17 GHz.Secondly,Zn-Mn ferrite(ZMF)and MXene were compound to prepare MXene@ZMF hybrid materials were prepared by co-precipitation method.The hybrid materials were characterized by XRD,SEM,FTIR and XPS analysis.The effects of the mass ratio of MXene and ZMF on the absorbing properties of hybrid materials were studied.The results showed that the RL_min values of the hybrid material increased and then decreased with a decrement of the MXene content.The MXene@ZMF-80%composites in this work show the minimum absorption intensity of-69.86 dB.Ultimately,the silicone rubber foam composites were prepared by mixing MXene or MXene@ZMF with liquid silicone rubber by using the principle of silicone hydrogen foaming.Then the morphology,density,electromagnetic properties and microwave absorption properties of the composites were investigated.The results showed that with the increase of the MXene content,the microwave absorption performance of the composites is enhanced,however,the density also increases.The MX/SRF-50%composite with a density of 1.11g·cm^-3 has good overall performance with a RL_minvalue of-55.83 dB and EAB of 3.92 GHz when the sample thickness is only 1.59 mm.Compared with the MX/SRF-50%composite,the MX@ZMF80%/SRF-50%composite has a similar density but higher absorption intensity.