Effect of electric-field-assisted thermal annealing of poly(4-vinylphenol) film on its dielectric constant

We investigated the effect of annealing a polymeric dielectric film in the presence of an oscillating electric field on its dielectric constant. Films were prepared with the vertical structure of electrode/poly(4-vinylphenol)/electrode and annealed at a temperature above the glass transition temperature while applying an ac electric field ranging from 0to6V at various frequencies in the hope of altering the arrangement of polymer chains through conformational transitions influenced by the orientational polarization of the polar phenol groups. It was found that the dielectric constant increased significantly by about 30% when the annealing frequency corresponded to that at which dielectric relaxation takes place effectively.