Proton exchange membrane based on crosslinked sulfonated polyphosphazene containing pendent perfluorosulfonic acid groups with sulfonated poly(ether ether ketone)

Abstract

A series of crosslinked membranes based on new sulfonated polyphosphazene bearing pendent perfluorosulfonic acid groups (PMFP-g-PS) and sulfonated poly (ether ether ketone) were prepared and evaluated as proton exchange membranes for direct methanol fuel cells (DMFCs). The structure of PMFP-g-PS was characterized by Fourier transform infrared spectroscopy, 1 H and 19 F NMR spectra. In comparison with the pristine PMFP-g-PS membrane, the crosslinked membranes showed improved water uptakes and proton conductivities. The methanol permeability values of the membranes were in the range of 1.32 3 10 27 to 3.85 3 10 27 cm 2 /s, which were lower than Nafion 117 (12.1 3 10 27 cm 2 /s). The selectivity of all the membranes was much higher compared with Nafion 117. Furthermore, transmission electron microscopy observation revealed that clear phase-separated structures were well dispersed and connected to each other in the membranes. These membranes displayed high water uptakes and low swelling ratios, high proton conductivities, low methanol permeability values, good thermal, and oxidative stabilities. The results indicate that these membranes are potential candidate proton exchange membrane materials for DMFCs. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43492.

Self-Cross-Linked Sulfonated Poly(ether ether ketone) with Pendant Sulfoalkoxy Groups for Proton Exchange Membrane Fuel Cells

“…However, a high sulfonation degree (SD) is generally needed because the conductivity of SPEEK generally increases with SD, which may decrease the dimensional stability of the hydrated membrane and affect its long-term use. , A number of methods have been tried to overcome the shortcomings of PEMs mentioned above, including the construction of cross-linked structures − and the introduction of aliphatic flexible side chains − to form distinct hydrophilic–hydrophobic microphase separation. Cross-linking can reduce the undesirable swelling and maintain the mechanical stability and durability of PEMs. , For example, Han et al prepared a cross-linked SPEEK by using poly­(2,5-benzimidazole)-grafted graphene oxide as the cross-linker, which exhibited remarkably decreased water uptake (WU) and swelling ratio (SR) and improved chemical stability, while the pristine SPEEK membrane showed a high WU and cracked at 60 °C due to excessive swelling .…”

Polyaniline decorated graphene oxide on sulfonated poly(ether ether ketone) membrane for direct methanol fuel cells application

“…In order to overcome these limitations, protogenic groups (SO 3 H, PO 3 H, and COOH) are attached on the surface of GO to improve its dispersion in various polymer matrix and enhance proton conductivity. [21][22][23][24][25][26] Polyaniline (PANI) has been widely used as a conductive polymer additive to modify PEM to improve the fuel cell efficiency. It is preferred due to properties such as hydrophilicity, tunable electrical conductivity, ease of synthesis, chemical stability, and environmentally stable.…”

Polymer Electrolytes: Ionic Liquid Modified Phenolphthalein Based Hybrid Multiblock Poly(Arylene Ether) Copolymers

“…14 Many articles on the hydrophobic-hydrophilic based multiblock copolymer PEMs, such as based on polystyrene, polyimide, polybenzimidazole, polyphosphazene and more specifically poly (arylene ether) multiblock copolymers suggest that the chemical structure, degree of sulfonation and the length of hydrophobic-hydrophilic segments have influential impact on the performance of PEMs. [15][16][17][18][19][20] In our previous work, we synthesized the random poly (arylene ether sulfone) copolymers and crosslinked them with epoxy resins to prepare crosslinked PEMs. The mechanical and thermal stability of the membranes undoubtedly increased, but at the cost of decrease in water uptake and proton conductivity.…”