Microwave dielectric constant measurements of strontium titanate using five mixture equations

The microwave dielectric constant of strontium titanate ceramic dispersed in the polyethylene matrix is studied by powder mixture equations in this article. The experimental dielectric constant values of the mixtures are compared to the theoretical curves of five published mixing rules. A new empirical mixture equation is proposed. The dielectric constant of pure strontium titanate is then estimated by these mixing laws from the dielectric constants of composites of various filler concentrations. The theoretical errors of estimations of various rules are derived and analyzed. The new empirical mixture equation has shown good accuracy for the dielectric constant measurement of strontium titanate.