Synthesis and characterization of a new network polymer electrolyte containing polyether in the main chains and side chains

Abstract

A new network polymer electrolyte matrix with polyether in the side chains and main chains was synthesized by the azo-macroinitiator method and urethane reaction. The macroinitiator, polymer and network polymer were confirmed by Fourier-transform infrared (FT-IR) spectroscopy and 1H NMR. FT-IR was also used to study the environment of lithium ions doped in these network polymer electrolytes. Three important groups are considered: N–H, carbonyl, and ether groups. The thermal properties of the polymer electrolytes were measured by differential scanning calorimetry and thermogravimetric analysis. The T g value of this polymer is less than that of a general comb-like polymer. Added lithium ions interact with the oxygen atoms on ether groups, causing the T g of the polymer electrolyte to increase. Moreover, the interaction between lithium ions and ether groups decreases the decomposition temperature of the polymer. The conductivity measured by AC impedance reached a maximum of 10 −4 S cm −1. A plot of conductivity vs. temperature fit the Vogel–Tamman–Fulcher equation, indicating that ionic mobility in this network polymer electrolyte is coupled to segmental chain movements.