Modulation of the electrochemical properties of SBS-based anionic membranes by the amine molecular structure

In this work, different amines (bifunctional, as diazabicyclo[2.2.2]octane (Dabco) and monofunctional, as N-methylimidazole or trimethylamine) were utilized for the amination of benzyl chloride-grafted polystyrene-b-poly(butadiene)-b-polystyrene triblock copolymers (SBS-g-VBC). The use of Dabco solutions in mixture with variable amounts of monoamine or at different concentration allowed to modulate the degree of crosslinking of the SBS-based membranes and their electrochemical parameters. More specifically, tuning Dabco concentration permitted the reduction of water uptake without significantly affecting ionic conductivity.