| Shielding is one of the major methods in avoiding Electro-Magnetic Interference (EMI) to the electronic equipment and devices. As one of Structural Conductive Polymers, polypyrrole (PPy) becomes a new kind of EMI shielding material because of its advantages such as tunable conductivity, outstanding shielding effectiveness and good temperature stability.The thesis aims to prepare the conducting PPy film by chemical polymerization method on the surface of plastic materials for electronic packaging. The shielding effectiveness was measured by flange coaxial transmission device and the samples were characterized by scanning electron microscopy (SEM). Furthermore, we studied the influence factors of shielding effectiveness and the relation of film conductivity and microstructure through finite elements analysis method, the error analysis between theory calculation and actual measurement was also conducted. In order to improve the EMI shielding effectiveness and surface morphology of the PPy film, We do some experiments which includes the influences of Silane Coupling Agents (SCA), dopants, proportions between pyrrole and ethanol on the conducting PPy film.The results show that the EMI shielding effectiveness and surface morphology of the PPy film are influenced by many factors. SCA can enhance the binding force between membrane and substrate and modify the surface morphology of the PPy film, which improve the EMI shielding effectiveness. As the solvent of SCA, distilled water has better performance than ethyl alcohol. Aminopropyltriethoxy silane is more suitable than vinyltriethoxy silane to the plastic substrates in our research. Dopants can also increase the EMI shielding effectiveness of PPy film, and NaTSA as one kind of dopants appears better effects than NaDBSA. Comparison studies with different proportion between pyrrole and ethanol show that proportion of 1:2 can get a compact PPy film with satisfactory EMI shielding effectiveness.
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