Enhancement of the shielding effectiveness of multilayer materials by gradient thickness in the stacked layers

Nowadays, with the proliferation of commercial scientific, electrical devices and equipments in high frequencies, the electromagnetic interference (EMI) becomes an important problem because this EMI can disturb the function of electronic circuits. Metals are particularly suitable as shielding materials against (EMI) due to their high electrical conductivity, however, there are few drawbacks to use metals as shielding materials. The weight of the 'heavy' metal can be an issue in the case of full metal shielding especially in applications where mass should be as low as possible. Conducting polymers have received much attention because of its unique high electrical conductivity ease of preparation and low cost. polyaniline-polyurethane (Pani/PU) Composites are required in many engineering applications, especially electromagnetic compatibility. The purpose of this study is to enhance the shielding of electronic circuit by using multilayer structure. We propose a new multilayer structure shield with a gradual increase thickness in each layer stacked in that shield, this structure is based on two Kapton dielectric layer sandwiched between three conductive layers of Pani8.8/PU for better protection against electromagnetic waves. The simulation results prove that the proposed five-layered material exhibits very good electromagnetic interference shielding efficiency compared to the previously developed Pani8.8/PU monolayer and three-layered in the frequency range (0.8-1.8 GHz) and is a potential candidate for several EMI shielding applications.