Conductivity and transport properties of starch/glycerin-MgSO4 solid polymer electrolytes

The thin films of solid polymer electrolytes were based on corn starch doped with magnesium sulphate (MgSO4) with different ratios of polymer and salt added. They were prepared using a single-solvent technique. The glycerin was added to the mixture of the solution to offer more elasticity to the polymer film and by increasing the flexibility of the thin-film membrane. The conductivity and electric studies were carried out on these thin films to understand the ion transport properties of the polymer electrolytes. The highest conductivity obtained was 8.52 10 -5 S cm -1 , which for the 35 wt. % MgSO4 salt-doped polymer electrolyte system at room temperature. From the evaluation on the transport properties, the conductivity of the system was generally influenced by n, and D of charge carriers. MgSO4 helped to increase the ionic conductivity and further increase the salt content, while the diffusion coefficient and mobility of charge carriers were increased.