Electrical Properties Study of Solid Polymer Electrolyte based on PolyCaproLactone/LiCF₃SO₃ Added Plasticizer

The electrical properties of solid polymer electrolyte based on biodegradable polymer PolyCaproLactone (PCL)/LiCF₃SO₃ with PC plasticizer addition have been studied. Polymer electrolyte membranes were prepared by solution casting technique by varying propylene carbonate (PC) composition (0-60) % weight. The membranes were characterized by the Electrical Impedance Spectroscopy at room temperature to measure its ionic conductivity and other electrical properties such as dielectric constant and tangent loss. The PCL/LiCF₃SO₃ system containing 20% weight PC plasticizer exhibits the highest conductivity of 4.92 x 10⁻⁴ S/cm at room temperature. The dielectric constant shows decreases with frequency increasing and it depends on dissociation of ions in the polymer electrolyte system. The tangent loss suggests that there are relaxing dipoles in the polymer electrolyte that shift toward higher frequency region. The membrane microstructure also investigated by XRD and the result showed that the PC plasticizer made the PCL/LiCF₃SO₃ system become more amorphous