Studies on the Properties of Plasticizer and Lithium Salt on PMMA-based Solid Polymer Electrolytes

The effects of plasticizer and lithium salt on PMMA‐based solid polymer electrolyte have been investigated. In current project, three system samples consisted of pure poly(methyl methacrylate (PMMA) system, plasticized poly(methyl methacrylate) (PMMA‐EC) system and the LiCF3SO3 salted‐poly(methyl methacrylate) containing a fixed amount of plasticizer ([PMMA‐EC]‐LiCF3SO3) system have been prepared using solution casting technique. The conductivities of the films from each system are characterized by impedance spectroscopy and infrared spectrum. With the addition of plasticizer, results show improvement on the ionic conductivity value where the value of 6.25×10−10 Scm−1 is obtained. This may be due to the nature of plasticizer that softens the polymer and hence enhanced the ionic transportation across the polymer. The room temperature conductivity for the highest conducting sample in the ([PMMA‐EC]‐ LiCF3SO3) system is 1.36×10−5 Scm−1. Fourier Transform Infrared Spectroscopy (FTIR) indicates complexation between the polymer and the plasticizer and the polymer, the plasticizer and the salts, and the result of XRD further supports the observation.