Mixed phase solid polymer electrolytes based on poly(methylmethacrylate) systems

A composite polymer electrolyte PMMA–Li2SO4–DBP–ZrO2 was prepared by a solution casting technique; poly(methymethacrylate) (PMMA), dibuthylphalate (DBP). A conductivity of 0.13×10−6 S cm−1 can be achieved at room temperature for the composition PMMA–Li2SO4–DBP (25–5–70 mol%), whereas it improves an order of magnitude (7.5×10−6 S cm−1) upon dispersing fine particles of ZrO2 (particle size = 21.5 μm) as inert fillers into the above plasticized polymer electrolyte matrix. The role of the ceramic phase is to reduce the melting temperature and to retard the kinetics of crystallization of PMMA. This results in a conductivity relaxation below the melting temperature of PMMA, which appears to be a characteristic of these composite electrolytes.