1.D.259.  The PEG-grafted Poly(Terphenyl Piperidinium) Anion Exchange Membrane (PEG-PTP-AEM) Family 

Poly(ethylene glycol) (PEG) or oligo (ethylene glycol) (OEG) grafted anion exchange membranes (AEMs) exhibit improved ionic conductivity, high alkaline stability, and subsequent boosted AEM fuel cell performance, but too many PEG/OEG side chains may result in a reduction in the ion exchange capacity (IEC), which can have adverse effects on ion transport. A series of partially PEG-grafted poly(terphenyl piperidinium) with different side chain lengths were synthesized using simple postpolymerization modification to produce AEMs with balanced properties. The polar and flexible PEG side chains were responsible for the controlled water uptake and swelling, superior hydroxide conductivity (122 mS cm^-1 at 80 °C with an IEC of 1.99 mmol g^-1), and enhanced alkaline stability compared to the reference sample without PEG grafts (PTP). The performance of the AEM fuel cell with the membrane containing partial PEG side chains surpassed that with PTP membranes, demonstrating a highest peak power density of 1110 mW cm^-2 at 80 °C under optimized conditions. This work provides a novel approach to the fabrication of high-performance AEM materials with balanced properties for alkaline fuel cell application.