Novel sulfonated poly(arylene ether sulfone) containing hydroxyl groups for enhanced proton exchange membrane properties

Abstract

We here report a new sulfonated poly(arylene ether sulfone) modified with hydroxyl side groups for a proton exchange membrane fuel cell (PEMFC).

Novel Sulfonated Co-poly(ether imide)s Containing Trifluoromethyl, Fluorenyl and Hydroxyl Groups for Enhanced Proton Exchange Membrane Properties: Application in Microbial Fuel Cell

“…The WU values of DHN-XX copolymer membranes are marginally higher than that of analogous DAN-XX copolymer membranes with the same DS or similar ion exchange capacity (IEC) values (Table ). It was expected that the additional Ar–OH groups in DHN-XX copolymers should increase the water uptake values of these membranes through formation of a hydrogen-bonded water network . At the same time, the hydroxyl groups in DHN-XX copolymers may also participate in hydrogen bonding with the sulfonic acid groups and that eventually may reduce the WU values .…”

“…At room temperature, an increase in proton conductivity was observed in DHN-XX copolymers compared to analogous DAN-XX copolymers with the same DS values, e.g., the proton conductivity of DHN-70 was increased by 30% compared to the analogous DAN-70 with similar IEC values. This is due to the higher WU of DHN-XX copolymers and the presence of phenolic – OH groups that form hydrogen bonds with the water molecules through electrostatic forces of attraction. , By that, water channels are formed that are responsible for attaining large and connected ionic clusters that led to a higher proton conductivity of the DHN-XX copolymers compared to the DAN-XX copolymers, despite having similar IEC values. ,, The DHN-XX copolymers also showed higher proton conductivity at relative humidity (RH) of 60 and 80% than the DAN-XX copolymers. This is because the phenolic −OH groups are assisting to the sorption of more water in the closely spaced ionic clusters, which results in the enlarged ionic clusters through hydrogen bonding.…”

“…Accordingly, over the years, a large number of hydrocarbon-based sulfonated copolymers were developed by several researchers, such as sulfonated copolyimides (S-coPIs), − sulfonated copoly­(arylene ethers) (S-coPAEs), − sulfonated copoly­(ether ether ketones) (S-coPEEKs), , sulfonated copoly­(benzimidazoles) (S-coPBIs) , and sulfonated copoly­(triazoles) (S-coPTAs). , Among these, S-coPIs exhibited high thermal, chemical, and mechanical stability. However, these polymers have limited solubility, low proton conductivity at a low degree of sulfonation (DS), and poor chemical and peroxide stability at high DS.…”

Synthesis of Sulfonated Poly(Arylene Ether Sulfone)s Containing Aliphatic Moieties for Effective Membrane Electrode Assembly Fabrication by Low-Temperature Decal Transfer Methods

“…The titrated values of the membrane IECs were measured according to the classical titration method using phenolphthalein as an indicator [ 18 ]. After weighing the dried membrane, it was immersed in a 2 M sodium chloride solution for 48 h at 20 to 25 °C.…”

Recent Progress on the Key Materials and Components for Proton Exchange Membrane Fuel Cells in Vehicle Applications

“…The dimensional stability and oxidative Energies 2016, 9, 603 9 of 39 durability of the modified SPAES was enhanced, the tensile strength was 47.3-64.5 MPa, the thermal stability was up to 260˝C, and the proton conductivity was 0.35 S/cm at 90˝C for 99.3% sulfonation. In the side chain modification study, Kwon et al [40] modified the SPAES side chain with hydroxyl side groups contributing additional hydrogen bonding. Thereby, the interconnected hydrophilic clusters and the extent of hydrophobic-hydrophilic microphase separation were enhanced.…”