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Showing 1 to 11 of 11 for “"perfluorosulfonic acid"”.
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Structure-Morphology-Property Relationships in Perfluorosulfonic Acid Ionomer Dispersions, Membranes, and Thin Films to Advance Hydrogen Fuel Cell Applications
… side chains terminating in sulfonic acid groups, called perflurosulfonic acid ionomers (PFSAs). The purpose of this dissertation is to investigate the effects of industrial processing parameters such as dispersion solvent composition, solvent evaporation temperature, and annealing …
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Polymeric and Polymer/Inorganic Composite Membranes for Proton Exchange Membrane Fuel Cells
… is high methanol crossover. Nafion, the current perfluorosulfonic acid copolymer benchmark membrane for both DMFCs and hydrogen/air fuel cells, shows very high methanol crossover. Directly copolymerized disulfonated poly(arylene ether sulfone)s copolymers doped with zirconium phosphates and …
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Chemical and Physical Modifications of Semicrystalline Gels to Achieve Controlled Heterogeneity
… Moreover, Ullmann coupling introduced superacidic perfluorosulfonic acid side chains to the BrPEEK backbone, which yielded membranes with less water content and less dimensional swelling than random SPEEK. Superior proton transport than random SPEEK was observed due to the superacid side …
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SYNTHESIS OF PERFLUOROHETEROAROMATIC POLYMERS FOR ION-CONDUCTING MEMBRANE FUEL CELLS VIA FREE RADICAL-BASED REACTIONS AND SYNTHESIS OF DI-CATIONIC IONIC LIQUIDS AS EFFICIENT SO2 ABSORBENTS
… grafting aromatic/heteroaromatic compounds to perfluorosulfonic acid polymers (PFSAs). Two proton-exchange membranes perfluorobenzoic acid (PFBA) and perfluorobenzenesulfonic acid (PFBSA)—were synthesized for proton-exchange membrane fuel cells via the free radical-based reaction. The physical …
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Low PGM PtCo alloy catalysts for low loading Polymer Electrolyte Membrane Fuel Cells
… a reduced cost. The catalyst is combined with a perfluorosulfonic acid (PFSA) ionomer which serves as the proton conductor and binder to form the catalyst layer (CL). The ionomer contains both hydrophilic and hydrophobic groups, and therefore plays a key role in water management in the fuel cell. …
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Transport and Structure in Fuel Cell Proton Exchange Membranes
… copolymers and the state-of-the-art poly(perfluorosulfonic acid) copolymer membrane for fuel cells, Nafion, were compared. Species transport (protons, methanol, water) in hydrated membranes was found to correspond with the water-self diffusion coefficient as measured by pulsed field …
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Development of novel catalysts coated non-fluorinated proton exchange membranes for water electrolysis
… in PEM technology with the development of poly perfluorosulfonic acid (PFSA)-based membranes. These membranes offer high proton conductivity, exceptional chemical stability, and mechanical strength under vari-ous conditions, thanks to the strong C–F bonds in their molecular structure. However, …
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Influence of Sidechain Structure and Interactions on the Physical Properties of Perfluorinated Ionomers
… on the morphology and physical properties of perfluorosulfonic acid ionomer (PFSA) membranes. One of the primary objectives was to characterize the thermomechanical relaxations for short sidechain PFSAs developed by 3M and Solvay, as well as a new multi-acid sidechain perfluoroimide acid …
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Evaluation of process parameters and membranes for SO2 electrolysis
… for the production of hydrogen and sulphuric acid, using commercially available PFSA (perfluorosulfonic acid) (Nafion®) as benchmark by evaluating i) various operating parameters (such as cell temperature and membrane thickness), ii) the influence of MEA (membrane electrode assembly) …
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High Performance Disulfonated Poly(arylene Sulfone) Co- and Terpolymers For Proton Exchange Membranes For Fuel Cell And Transducer Applications: Synthesis, Characterization And Fabrication Of Ion Conducting Membranes
… well or better than the state of the art Nafion perfluorosulfonic acid membrane. Direct aromatic nucleophilic substitution polycondensations of disodium 3,3′ S-disulfonate-4,4′ S-difluorodiphenylsulfone (SDFDPS), 4,4′ S-difluorodiphenylsulfone (DFDPS) (or their chlorinated analogs, SDCDPS, DCDPS) …
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Properties and Performance of Polymeric Materials Used in Fuel Cell Applications
… highly arranged perfluorinated sulfonic acid ionomer (PFSI) membranes with more favorable organization of the ionic domain. Moreover, thermal annealing was shown to enhance the proton mobility, thereby facilitating reorganization of the polymer backbone and the hydrophilic region for …