Effect of plasticizer on the electric-field-induced adhesion of dielectric PVC gels

Four different plasticizers have been used to make the PVC gels: poly(vinyl chloride)–diethyl adipate (PVC–DEA), poly(vinyl chloride)–dibutyl sebacate (PVC–DBS), poly(vinyl chloride)–dioctyl phthalate (PVC–DOP) and poly(vinyl chloride)–dibutyl phthalate (PVC–DBP). The chemical structure and molecular weight of the plasticizers significantly affected the electric-field-induced adhesion of the gels. To explain the variations, the dielectric properties, space charge distributions, tensile properties and Raman spectra of the PVC gels were compared. Aliphatic ester (DEA and DBS) plasticizer-containing PVC gels showed larger electric-field-induced adhesion and dielectric constants than phthalate plasticizer (DBP and DOP)-containing gels. Raman spectroscopy suggested that there were different molecular interactions between PVC and the plasticizers. The dielectric constant and mechanical properties of the PVC gels were determined to be the key factors for determining the electric-field-induced adhesion.