Multifunctional Sulfonated Polytriazoles: Proton-Exchange Membrane Properties, Molecular Logic Gates, and Modeling of Stimuli-Responsive Behaviors

A series of new sulfone-based sulfonated copolytriazoles (PTSFDSH-60 to 90) with different degrees of sulfonation was designed and successfully synthesized using click polymerization. The high-molecular-weight copolytriazoles were characterized by NMR and FTIR techniques. The solution-cast membranes of the copolytriazoles possessed high mechanical (85–131%) and thermomechanical stability (>300 °C) and exceptional thermal steadiness. The multifaceted structural units and stability of copolytriazoles made them to act as multifunctional polymers for various applications. The presence of high ionic contents and a well-distributed phase-separated interconnected morphology among hydrophilic–hydrophobic domains in the membranes resulted in exceptionally high proton conductivity (62–202 mS cm–1). Additionally, the membranes showed sufficient oxidative stability (>13.5 h) for their applications as polyelectrolyte membranes in a fuel cell. The polymers exhibit significant absorption and photoluminescence that varied significantly with the external stimuli (acid and temperature). The molecular logic gates (NOR gate and fuzzy logic operations) were constructed for information processing at the molecular level by monitoring the stimuli-responsive emission characteristics. In addition, to save time, effort, and expenses, a computational model [fuzzy logic operation and adaptive neuro-fuzzy inference system (ANFIS)] was developed to predict the emission behavior of the copolytriazole with temperature and acid as input parameters.