| 초록 |
Recently there are a lot of interests in polymer composites with nano-sized fillers because of their transparency, flexibility and tailorable dielectric properties. Especially in power electronics, to satisfy required features of dielectric materials like high permittivity, low loss, high breakdown strength and high energy density there have been various attempts to increase the dielectric constant. To increase dielectric permittivity of polymer composites, metal particles including silver, nickel and aluminum are introduced but when increasing metal filler volume fraction, metal particles aggregate and form large particle clusters. Most of them become self-connected to form a continuous percolation cluster at a critical volume fraction. This percolation phenomenon increases the dielectric constant but at the same time this phenomenon could make huge loss and lower breakdown strength, so in dielectrics the percolation should be avoided. In this study, nanocomposites were synthesized 2-d nanofillers using silver nanoparticles on mica nanosheets and PVDF based polymer. The formation of Ag@mica nanofiller was confirmed by XRD and FT-IR. The dielectric constant, loss, PE loop, leakage current and maximum nanofiller volume fraction of the nanocomposites were measured in wide frequency range. |
