Synthesis and electrochemical properties of ion exchange membrane based on crosslinked styrene-(2-hydroxyethyl acrylate)-lauryl methacrylate copolymer

Abstract

The copolymer, Sty-HEA-LMA, was synthesized by solution polymerization based on styrene (Sty), 2-hydroxyethyl acrylate (HEA), and lauryl methacrylate (LMA). The synthesized copolymer was crosslinked with sulfosuccinic acid (SSA) and glutar aldehyde (GA) via esterification. The sulfonation reaction was performed to introduce sulfonic groups into the membrane with sulfuric acid as the sulfonating agent. The chemical structures of the membranes were characterized by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy ( 1 H NMR), respectively. The basic membrane properties, such as the water uptake, ion exchange capacity (IEC), ion transport number and electrical properties, were measured for the prepared ion exchange membranes. The IEC value and electrical conductivity increased with increasing sulfonation time due to the ionic group (-SO 3 H), and were in the range of 0.31-1.15 meq/g and 0.5×10 -4 -0.1 S/cm, respectively.