Hopping transport and relaxation phenomena in poly (vinyl chloride: vinyl acetate: Vinyl alcohol) terpolymer

Abstract

Dielectric measurements have been made on poly (vinyl chloride: vinyl acetate: vinyl alcohol) in the frequency range 30 Hz-100 KHz and in the temperature range 77–410 K. A frequency dependent conductivity described by σ(ω) = A ω^s, is observed where S < 1 and is independent of temperature upto 250 K but with further increase in temperature it decreases. Two relaxations, the α-and the β-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 β-relaxation is due to the C-C1 dipoles in the amorphous phase of the terpolymer.