Dielectric and relaxation behaviour studies in acrylonitrile-methylacrylate copolymer

Abstract

Poly(acrylonitrile-methylacrylate) copolymer is a semicrystalline material, as defined by X-ray diffraction, and is thermally stable up to 425 K as revealed by infrared investigations. The study of dielectric properties obtained from this copolymer allows us to follow the relaxation processes and showed the difference between three processes; β-, α- and ρ-relaxations. The first two processes occur in the two phases, amorphous and crystalline, and the third process is associated with the glass transition temperature. The origins of these processes were attributed to local motion of the polymer backbone segments, to a dipole orientation of the chain side groups and to an ionic space-charge relaxation, respectively.