The conductivity and characterization of the plasticized polymer electrolyte based on the P(AN-co-GMA-IDA) copolymer with chelating group (II): The effect of free ion in the plasticized polymer electrolyte

A new gel-type polymer electrolyte (GPE) was made by the copolymerizing acrylonitrile (AN) and (2-methylacrylic acid 3-(bis-carboxymethylamino)-2-hydroxy-propyl ester) (GMA-IDA). The copolymer mixed with a plasticizer—propylene carbonate (PC) and lithium salt to form GPE. The lithium salts are LiCF3SO3, LiBr and LiClO4. FT-IR spectra show that the lithium ion in the LiClO4 system has the strongest interaction with the group based on the plasticized polymer. FT-IR spectra also indicate that CF3SO3− prefers producing anion–cation association. Moreover, the 13C solid state NMR spectra for the carbons attached to the PC of GPE exhibited different level of chemical shift (158.5 ppm) when the different lithium salts were added to the electrolyte. The results of differential scanning calorimeter (DSC) also indicate that the LiClO4 system has more free lithium ions; therefore, it has the maximum conductivity. In this study, the highest conductivity 2.98 × 10−3 S cm−1 exists in AG2/PC = 20/80 wt.% system which contain 3 mmole (g-polymer)−1 LiClO4. Additionally, the polymer electrolytes, which contain GMA-IDA have better interfacial resistance stability with lithium electrode.