Studies Of Preparation, Structure And Properties Of Novel Nanocomposites For Microwave Absorbing

New materials with electromagnetic wave absorption function must be suitable for the requirements in technique of strong absorption, light weight, wide frequency band, absorbing both microwave and infrared ray and other excellent properties. An effective way to meet the requirements is that preparing nanocomposites able to absorb the wave are made by taking advantage of the extraordinary properties of nanoparticles in electromagnetism and optics and the excellent properties in other ways. Among many absorbing materials, polyaniline(PANI) and hexagonal barium ferrite (BaFe₁₂O₁₉) were common and better in the absorbing property. The study was devoted to find out a convenient and suitable way by which PANI or BaFe₁₂O₁₉ can be intercalated into the inner layer of montmorillonite(MMT) to prepare a novel nanocomposites for microwave absorbing. The structure, properties and interrelated influence factors were also analysed and discussed systematically. The collelative reports have not been seen in all of literatures.The purification and sodium-modification process of MMT were researched primarily. The influence factor and mechanism of it were discussed and analysed in detail. The ideal structure model verification of MMT structure according to its crystalline element.Based on this, a series of PANI/MMT nanocomposite with different content of MMT have been successfully synthesized by three different ways, ie, in-situ polymerization with MMT by using HCl and camphorsufonic acid as doped reagent respectively and emulsion polymerization with MMT by using dodecylbenzensulfonic acid as dopant and emulsifier. The nature of this kind of PANI/MMT nanocomposite is signified through the X-ray diffraction, FT-IR, and conductance mensurate. The basic electromagnetic characteristics of it are measured by the use of a microwave vector network analyzer.The X-ray diffraction patterns shows that the insertion of PANI chains between the interlayer of the MMT was in nanoscale. The FT-IR spectrum of PANI/MMT nanocomposite denotes that PANI produced in the form of emeraldine salt, which absorption peaks was...