Dielectric constants and electrical conductivities of sodium dodecyl sulfate in aqueous solutions

Abstract

Dielectric properties of sodium dodecyl sulfate in aqueous solution have been studied. The dielectric constant and ac electrical conductivity were measured in the frequency range 30 Hz to 6 MHz. At lower frequencies, with increasing concentrations of sodium dodecyl sulfate, dielectric properties were greatly affected by polarization on the surfaces of the electrode, the so-called space charge polarization. ac electrical conductivities were dependent on the concentration of sodium dodecyl sulfate at all frequencies. The activation energies of de electrical conduction were much larger in the molecular state than in the aggregation state. The radius of a spherical particle with an electric double layer could be calculated through the measurement of dielectric constant and de electrical conductivity.