Hoppijg Transport and Relaxation Phenoiena in Poly(Vinyl Chloride: Vinyl Acetate: Vinyl Alcohol) Terpolymer

Dielectric measurements have been made on poly(vinyl chloride: vinyl acetate: vinyl al cohol) in the frequency range 30 Hz to 100 kHz and in the temperature range 77 to 410 K. A frequencydependent conductivity described by σ(w) = Aws is observed, where s<1 and is independent of temperature up to 250 K but decreases at higher temperatures. Two relaxations, the α- and the ß-relaxation, are observed having activation energies ≃0.92 and ≃0.42 eV, respectively. The α-relaxation is attributed to the segmental motion of the main chain consisting of the constituent groups of the terpolymer under dipole-dipole interaction and the ß-relaxation is due to the C-Cl dipoles in the amorphous phase of the terpolymer.