Highly Conductive Ag/pCF/MVQ Composite Rubber for Efficient Electromagnetic Interference Shielding

In this study, flexible and highly conductive composite rubber at low filler content was successfully prepared through polydopamine-assisted electroless silver plating plus mechanical mixing. Firstly, carbon fibers (CF) were activated by polydopamine (PDA) to improve the surface activity by self-polymerization reaction. Next, because of the metal chelating ability of PDA, silver layer was firmly deposited on the surface of CF through a facile electroless silver plating method. Finally, flexible silver-plated carbon fibers (Ag/pCF) silicone rubber composites prepared by mechanical mixing. By using X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), the chemical composition and crystal structure of Ag/pCF were examined, and scanning electron microscopy (SEM) was used to assess the surface morphology of the Ag/pCF. The results showed that a uniform and dense silver layer was formed on the surface of the CF, and the conductivity of the Ag/pCF could reach 7885 S/cm. It was noteworthy that the composite rubber filled with only 45 phr Ag/pCF had a high electromagnetic interference shielding effectiveness (100 dB) due to the low density and high aspect ratio of Ag/pCF. The composite rubber has excellent potential for application in the field of electromagnetic interference shielding.