Dielectric Relaxation of Poly(n-butyl acrylate)

Dielectric relaxation of poly(n-butyl acrylate) (PBA) was studied over a temperature range from 90 to 300 K. The primary α relaxation was observed around 250 K but the relaxation due to motion of the side ester group as observed for poly(methyl acrylate) (β process) was not observed. Thus the α relaxation was assigned to a merged process where the segmental motions and the rotation of the side group occur cooperatively. A weak secondary (γ) relaxation was observed at 130 K at 1 kHz. The γ relaxation was assigned to motion of the alkyl group of the side chian. Dielectric characteristics such as relaxation strength, effective dipole moment, and Arrhenius plot for the α process were compared with those for poly(butyl methacrylate)s reported.