Fabrication, structure, and property of epoxy-based composites with metal-insulator core-shell structure fillers


The Ag@SiO2 core-shell structure nanoparticles prepared by chemical method were dispersed into epoxy matrix. By comparing with the epoxy-based composites filled with the mixed Ag and SiO2 nanoparticles (Ag + SiO2), it is found that the Ag@SiO2 core-shell structure fillers had important effects on the improved dielectric properties of the Ag@SiO2/epoxy composites. The core-shell structure fillers introduce a duplex interfacial polarization and a small number of free charge carriers, which enhance the dielectric permittivity of the composites. At the same time, the insulating SiO2 shell layer changes the interfacial interaction between the Ag filler and the epoxy matrix, not only avoiding Ag particles to connect directly and aggregate together but also providing a rough surface to contact with the epoxy host, which enhances the compatibility between the Ag@SiO2 fillers and the epoxy matrix. As the Ag@SiO2 packing ratio increases, the permittivity of the composites straightly increases and the loss tangent decreases, reaching the maximum and minimum respectively with the filler loading up to 60%.

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This work was supported by National Science Foun-dation of China (61025002) and National 973-project of China (2009CB623302).

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Correspondence to Hong Wang.

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Niu, Y., Bai, Y., Yu, K. et al. Fabrication, structure, and property of epoxy-based composites with metal-insulator core-shell structure fillers. Journal of Materials Research 28, 2644–2649 (2013). https://doi.org/10.1557/jmr.2013.248

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