On the evolution of sulfonated polyphenylenes as proton exchange membranes for fuel cells

Abstract

The recent expansion in proton exchange membrane (PEM) research has been commensurate with the growth of PEM fuel cell research. Perfluorosulfonic acid (PFSA) ionomer materials remain the technological membrane of...

Fully Hydrocarbon Membrane Electrode Assemblies for Proton Exchange Membrane Fuel Cells and Electrolyzers: An Engineering Perspective

“…Finally, to tackle tough scientific challenges in fuel cells and electrolyzers, Kim [8] discussed synthetic approaches, performance, challenges, and prospects of ionomers with high ionic concentrations (>>1.2 meq g −1 ) in the interesting review. The evolution of sulfonated polyphenylene as proton exchange membrane for fuel cells was summarized further in the recent published review article by Adamski et al [24] In the following sections, the main approaches in the development of hydrocarbon-based ionomers and their respective properties in the device are briefly summarized with focus on engineering properties in the membrane-electrode assembly.…”

“…The barrier for proton conduction in ionomers like PFSA or hydrocarbon-based ionomers can be estimated in form of activation energies. As activation energies typically decrease with increasing humidity, [117] and change with structural characteristic of an ionomer, the proton conductivity increases with higher degree of sulfonation, [24] higher acidity, [118,119] and/ or a more pronounced hydrophilic/hydrophobic phase separation. [117] Therefore, the activation energy may be used as an intrinsic characteristic to compare different novel hydrocarbon ionomers to state-of-the-art materials.…”

Piezoelectric sensor based on electrospun poly(vinylidene fluoride)/sulfonated poly(1,4‐phenylene sulfide) blend nonwoven fiber mat

“…12,27 Even a small amount of sPPS (10 wt%) added to PVDF increased the intensity of β-crystalline peak (1276 cm À1 ) significantly along with relative decrease in α-crystalline phase (764 cm À1 ) of PVDF (Figure 1c). Fraction of β-phase (F(β)) in PVDF 26 as a function of sPPS concentration is shown in Figure 1d. Compared to neat PVDF (48.31%), highest increase in F(β) value was observed for 10 wt% sPPS (66.27%), and further increase in sPPS content beyond 10 wt% exhibited almost a flat decreasing trend, which indicates that maximum increase of β-crystalline phase in PVDF as-cast films can be achieved using 10 wt% sPPS without the need for further addition of sPPS.…”

“…Among the many secondary components added to the neat PVDF, polyphenylene sulfide (PPS), an aromatic polymer consisting of benzene ring linked with para-substituted sulfides is used in the present study due to its many interesting characteristics such as high chemical and thermal resistance aided by its higher glass transition and melting temperatures of 90 and 280 C, respectively. [22][23][24] PPS itself has no polar group but its sulfonated form (sPPS) with polar SO 3 H groups has many advantages 25,26 : (a) sPPS can be easily dissolved in several polar solvents for solution blending with PVDF which can be readily used for electrospinning to form PVDF/sPPS nanofiber web, (b) PPS structure can undergo delocalization aided by the transfer of electrons from the sulfide linkages under the influence of applied electric field during the electrospinning process, which in turn may increase charge transfer throughout the PPS chain resulting in increased interactions between neighboring PVDF chains, and (c) the sulfonated groups in the side chain of sPPS can have iondipole interaction with PVDF, which may help in maintaining the preferential chain and dipole orientation in PVDF even after the completion of the electrospinning process. To date, no previous reports are available that deal with the electrospinning of sPPS or PVDF/sPPS blends and their piezoelectric studies.…”

Anion-Conducting Polymer Electrolyte without Ether Linkages and with Ionic Groups Grafted on Long Side Chains: Poly(Alkylene Biphenyl Butyltrimethyl Ammonium) (ABBA)

“…One of the main roles of the polymer backbone in AEM is to guarantee the mechanical stability by the interaction between chains by Van der Waals forces, by entanglements or by crystallinity [ 19 , 20 , 21 , 22 ]. The low chemical stability in alkaline media is a drawback: for example, in the case of polysulfone (PSU) the degradation in specific positions is promoted by the inductive effect of the sulfone groups [ 23 ].…”