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 alpha relaxation was observed around 250 K but the relaxation due to motion of the side ester group as observed for poly(methyl acrylate) (beta process) was not observed. Thus the a relaxation was assigned to a merged process where the segmental motions and the rotation of the side group occur cooperatively. A weak secondary (gamma) relaxation was observed at 130 K at 1 kHz. The gamma relaxation was assigned to motion of the alkyl group of the side chain. Dielectric characteristics such as relaxation strength, effective dipole moment, and Arrhenius plot for the alpha process were compared with those for poly(butyl methacrylate)s reported.