Realizing enhanced dielectric and mechanical performance of polyvinylidene fluoride/SiC nanocomposites through a bio-inspired interface design

The incorporation of high-dielectric permittivity ceramic or conductive fillers into the polymer is an effective method to obtain flexible high-performance dielectric materials, but it is still a huge challenge to achieve a balance between dielectric and mechanical properties. In this paper, we report a polyvinylidene fluoride (PVDF) nanocomposite based on a novel crab leg-like filler, in which Ag nanoparticles (AgNPs) were decorated on the surface of polydopamine (PDA)-coated silicon carbide (SiC) nanowhiskers (NWs). Compared with the nanocomposites with as-received SiC, this PVDF/SiC@PDA@Ag nanocomposites exhibited significantly suppressed dielectric loss (0.03 at 1 kHz) and leakage current. The Argant plot ( $${\varepsilon }^{^{\prime}}$$ - $${\varepsilon }^{\prime\prime}$$ curve) and electric modulus analysis demonstrated that the inhibition of the organic layer of PDA to interface polarization and the coulomb-blockade effect of AgNPs hindered carrier transport, which resulted in the largely suppressed dielectric loss. Furthermore, while the dielectric properties were improved, the PVDF/SiC@PDA@Ag nanocomposites also exhibited excellent mechanical and thermal conductivity. Ultimately, the nanocomposites prepared via this method are promising for applications in microelectronic devices.