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To meet the requirement of electromagnetic compatibility in various portable electronic devices, electromagnetic interference shielding effectiveness (EMISE) is one of the key parameters. Here, we demonstrate that a polymer composite film comprising two polymers poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] and poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) with good mechanical flexibility provides an effective electromagnetic interference (EMI) shielding. Dielectric properties of P(VDF-TrFE) and PEDOT:PSS composites in radio frequency ranges (10 MHz–1 GHz) have been utilized to calculate the EMI shielding properties in both near-field and far-field regions. The shielding properties for far-field region are also measured using the coaxial transmission method to verify the calculated result. The morphology of the obtained films was investigated by scanning electron microscopy, and the crystallinity of the composite films was investigated by X-ray diffraction and differential scanning calorimetry. The fabricated films with a thickness of ∼0.08 mm exhibit excellent EMI shielding properties. The films can be directly molded to a required shape with good mechanical strength. The film can find its application in fabricating electromagnetic compatible portable electronic devices mainly in the medical field where the EMISE measurement are made in the near field. Also the thickness of the shielding film will have minimum effect on the overall dimensions of device. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to develop a conducting composite sheet for coating of various electronic devices to provide effective electromagnetic interference (EMI) shielding in medical and defence application in near- and far-field region. Here, we utilize the dielectric properties of styrene acrylonitrile (SAN) copolymer and graphite (Gr) conducting composites in radio frequency ranges (10 MHz–1 GHz) for calculating EMI shielding properties. The SAN–Gr conducting composite sheets were prepared by mechanical mixing and the hot compression mold technique. The SAN–Gr conducting composites exhibited high dielectric constants $(\varepsilon^\prime)$ , high dissipation factors $(\tan \delta)$ , and high ac conductivities $(\sigma)$ in radio frequency regions. The main advantage of these composites incorporates their lightweight and low cost. The absorption loss (A), reflection loss (R), rereflection correction factor (C), and electromagnetic interference shielding effectiveness of the SAN–Gr conducting composite sheets were evaluated theoretically using $\varepsilon^\prime $ , tan $\delta $ , and $\sigma $ for near- and far-field region. For electromagnetic compatibility in near- and far-field region (electric field, magnetic field, and plane wave), the adequate shielding effectiveness in the frequency range of 10 MHz–1 GHz of the SAN–Gr conducting composites was obtained with addition of Gr content. [ABSTRACT FROM AUTHOR]