(381j) Molecular Transport of Aqueous Mixtures in Sulfonated Polyether-Based Ion Exchange Membrane

Understanding molecular transport in hydrated ion exchange membranes is crucial for promising energy technologies such as solar fuels devices. One of the major challenges with these applications is controlling molecular transport to prevent undesirable species crossover which impacts device performance. Polyethers are promising membrane materials due to their wide range of chemical functionalities and relatively facile fabrication technique, which involves UV-photopolymerization on diacrylate end groups. Sulfonates have been utilized as ion exchange functional groups in cation exchange membranes (i.e. Nafion 117). Membranes prepared from poly(ethylene glycol) diacrylate (PEGDA) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) have been used as a model system to investigate ion and molecular transport where permeability and selectivity are impacted by varying the PEGDA to AMPS ratio prior to photopolymerization allowing for variation in sulfonate and crosslink density. In previous work, our group has conducted direct permeation measurements using custom-built diffusion cells with in-situ ATR-FTIR spectroscopy to monitor concurrent multi-solute transport through ion exchange membranes. Here, we leverage this methodology to examine solution-diffusion transport of single and multiple solute through PEGDA/AMPS membranes. Finally, absorption-desorption experiments are conducted to determine solute solubilities to fully describe the transport behavior within these membranes.