Study of nonlinear nanoparticles doped silicone rubber composites and its dielectric properties

For the purpose of changing dielectric behavior of silicone rubber composites to obtain desirable dielectric properties, variety of inorganic particles fillers were doped into silicone rubber composites. In this paper we researched the dielectric properties of silicone rubber composites doped by nonlinear fillers, including zinc oxide(ZnO) with the size of 40nm and barium strontium titanate (BST) with the size of 200nm and measured the dielectric constant (ε
_r
), dielectric loss angle tangent (tanδ) and resistivity(ρ). Various mass fractions (0%,10% and 24%) of nanosized nonlinear powder (BST and ZnO)are doped into silicone rubber to obtain multi-phase dielectric composites. The parameters were measured at room temperature and different electric field with the intensity increased from 10
³
V m
^-1
to 10
⁷
V m
^-1
was applied. The result showed that BST and ZnO fillers tended to exhibit enhanced dielectric constant and lower tan because of the increase of effective mass fraction. The influence mechanism were discussed in accordance with the mass fractions, electric intensity and polarization mode of each kind of nonlinear fillers.