Title |
Nonlinear Dielectric Properties of VDCN Copolymers |
Authors |
강대하(Gang, Dae-Ha) ; 박상호(Park, Sang-Ho) |
Keywords |
complex permittivity ; dc conduction ; dielectric relaxation strength ; nonlinear dielectric effect factor ; dipolar correlation factor |
Abstract |
Linear and nonlinear complex permittivities were measured for copolymers of vinylidene cyanide(VDCN) with vinyl acetate(VAc), vinyl propionate(VPr), vinyl bezoate(VBz), styrene(St) and methyl methacrylate(MMA). Experimental results are well fitted by the function (equation omitted) except at low frequency where dc conduction dominates. The analysis of dielectric relaxation mechanism by combined knowledge about linear and nonlinear dielectric permittivities and dipoles give us informations about electrical and thermal motions in these copolymers. According to the analysis it could be found that the variation for temperature of the dielectric relaxation strength in these copolymers is related to the interaction between dipoles and the nonlinear dielectric effect factor R_{s} is proportional to square of the dipolar correlation factor R_{p}././. |