Polymer Electrolyte Membranes Prepared by Graft Copolymerization of 2-Acrylamido-2-Methylpropane Sulfonic Acid and Acrylic Acid on PVDF and ETFE Activated by Electron Beam Treatment

Abstract

Polymer electrolyte membranes (PEM) for potential applications in fuel cells or vanadium redox flow batteries were synthesized and characterized. ETFE (poly (ethylene-alt-tetrafluoroethylene)) and PVDF (poly (vinylidene fluoride)) serving as base materials were activated by electron beam treatment with doses ranging from 50 to 200 kGy and subsequently grafted via radical copolymerization with the functional monomers 2-acrylamido-2-methylpropane sulfonic acid and acrylic acid in aqueous phase. Since protogenic groups are already contained in the monomers, a subsequent sulfonation step is omitted. The mechanical properties were studied via tensile strength measurements. The electrochemical performance of the PEMs was evaluated by electrochemical impedance spectroscopy and fuel cell tests. The proton conductivities and ion exchange capacities are competitive with Nafion 117, the standard material used today.

Bio‐inspired proton conducting phytagel derived zwitterionic complex membranes for fuel cells

“…Although sPG‐SA membrane mechanical strength was low compared to sPG electrolyte, it retained appreciable mechanical robustness with self‐standing capability (Data S1: Figure S1) without electrolyte leakage, which makes them promising candidates for practical PEMFC applications. The obtained results strongly support proton conductivity results and are in consistent with the previous studies 8,51‐54 …”

On the Solubility and Stability of Polyvinylidene Fluoride

“…PVDF is not always inert to radiation, but high-energy radiation is required to form radicals on the PVDF chain. The radiation source can be UV [ 281 ], electron beam [ 282 ], heavy ions or gamma radiation [ 283 ]. Once irradiated, radicals are formed by bond scission between the carbon chain and the H or F substituents on the chain.…”

Characterization of Dimeric Vanadium Uptake and Species in Nafion™ and Novel Membranes from Vanadium Redox Flow Batteries Electrolytes

“…The HEMA monomer units of the membrane were sulfonated with 2-sulfobenzoic acid anhydride (94%, Alfa Aesar, Kandel, Germany). For experimental details the reader is referred to references [ 53 , 54 ]. In the following, the PVDF-based membrane is abbreviated in the figures as PEM-N—the N stands for novel.…”

“…In this work, Nafion™ 117, a well-investigated PEM in VRFBs, and a novel membrane based on poly(vinylidene difluoride) (PVDF) were studied. The novel membrane is comparable to Nafion™ with respect to chemical/mechanical properties and proton conductivity but potentially more cost efficient and tunable with respect to better ion selectivity [ 53 , 54 ].…”