ABSTRACT
Microwave absorbers (MAs) are widely applied in both military and civil fields on account of their ability to eliminate electromagnetic wave pollution and to prevent information leakage. The theoretical and experimental work with MAs was initially started in the mid-1930s1. After that, intensive attention was drawn to studying these functional devices. The characterizations of thin thickness, wide absorbing bandwidth, light weight, and strong absorption have gradually become the focus of the study on the electromagnetic wave absorbing and shielding fields both at home and abroad2. At present, absorbers fabricated in the form of sheets by mixing rubber or epoxy resin (ER) with absorbent powders have been become the focus of study because of their practical and simple preparation method. The effective absorption frequency band of an MA is narrowed as just adding a wave absorbent into the ER. To improve the absorption efficiency and effective absorbing band of the slab absorber, different methods are used, such as adding an optimized absorbent, compounding different types of absorbents, using special structures, etc. In addition, coupling agents are used to improve the adhesion between fillers and matrix resins by chemical reactions, which play an important role in improving the mechanical properties of a polymer composite. On the basis of the above analyses and summary of experiments, we can fabricate a suitable MA according to specific requirements.
