Flexible, Thin Composite Film to Enhance the Electromagnetic Compatibility of Biomedical Electronic Devices

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.