Effect of silver incorporation into PVDF-barium titanate composites for EMI shielding applications

Abstract Composites of polyvinylidene fluoride (PVDF) with micron and nano sized BaTiO3 powders were developed for electromagnetic interference (EMI) shielding applications in the X band. PVDF-nano BaTiO3 composites show better shielding property compared to PVDF-micron sized BaTiO3 composites. The composite of PVDF with 40 vol% of nano BaTiO3 showed the best EMI shielding effectiveness and is about 9 dB. The contributions from reflection and absorption to the total EMI shielding effectiveness is same for the PVDF-BaTiO3 composites. Addition of small amount of silver particles improved the shielding properties of these composites due to the increased conductivity. An EMI shielding effectiveness of about 26 dB is obtained in the measured frequency range for the PVDF-20 vol% nano BaTiO3-10 vol% Ag composite of thickness 1.2 mm. Novel three phase composite combining the advantages of metal, nano ceramic and polymer is obtained with the potential for effective EMI shielding applications.