LOW-FREQUENCY DIELECTRIC RESPONSE OF SOME CELLULOSE DERIVATIVES

The electrical properties of cellulose acetate and methyl cellulose free of inorganic impurities and contaminated with water soluble inorganic salts were measured in the frequency range 0.05-100 ke/s at 283-333 K temperatures. The results obtained show that the relation representing the variation with temperature of the real part of the dielectric permittivity with the samples examined exhibits a second order transition at about 303 K, and that, when these samples are contaminated with NaCl salt, such a relation takes plate exponentially, particularly at very low frequencies, and a real dielectric dispersion and a loss peak were found. The data have been discussed in view of the interfacial polarization that occurs in the case of inhomogeneous dielectric contaminated with inorganic impurities.