Synthesis and characterization of sulfonated polyphosphazene-graft-polystyrene copolymers for proton exchange membranes

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

“…PMMP‐ g ‐polystyrene copolymer was synthesized using an atom transfer radical polymerization (ATRP) . The macroinitiator PMMP‐Br (0.72 g, 2.6 mmol), styrene (1.083 g, 10.4 mmol), Bpy (3.65 g, 23.4 mmol), and CuBr (1.12 g, 7.8 mmol) were added to a dried reaction tube equipped with a stopcock and a magnetic stirrer.…”

“…In order to obtain high proton conductivity, low methanol permeability and low cost alternative PEMs, many kinds of sulfonated polymers with high ion exchange capacity (IEC) values have been developed as alternative materials to Nafion in the past decades, including sulfonated polyimide (SPI), sulfonated polysulfones (SPSFs), sulfonated polyphenylenes, sulfonated poly(ether ether ketone) (SPEEK), and sulfonated polyphosphazene . Among them, sulfonated polyphosphazenes are considered to be one of the most promising candidates because of their low methanol permeability, good chemical stability, and facile preparation process . Although these membranes with high IEC values can achieve sufficient conductivities, such membranes usually result in high water swelling and methanol permeability, making them impractical for use in DMFC applications.…”

Preparation and evaluation of crosslinked sulfonated polyphosphazene with poly(aryloxy cyclotriphosphazene) for proton exchange membrane

“…The membrane under test was immersed in deionized water for hydration before measurements and then vertically placed between the two compartments by a screw clamp [14] . Both solutions were stirred during testing to keep them homogenous.…”

“…In recent years, many polymeric membranes have been examined for use in fuel cells, including sulfonated poly(phenylene)s [8] , sulfonated polysulfones (SPSFs) [9] , sulfonated poly(ether ether ketone)s (SPEEKs) [10,11] , sulfonated polyimides (SPIs) [12,13] and sulfonated polyphosphazenes [14] . Among these materials, sulfonated polyphosphazenes have attracted considerable attention because of their low cost, acceptably high proton conductivities and low methanol permeability coefficients [15,16] .…”

A facile method for preparation of cardo poly(aryl ether sulfone) bearing pendent sulfoalkyl groups as proton exchange membranes

“…Aromatic hydrocarbon-based ionomers including sulfonated poly(arylene ether ketone) [4,5] , sulfonated polyimides [6,7] , sulfonated polystyrene-based systems [8] and sulfonated poly(benzimidazole) [9] have been suggested as alternative membranes in recent years due to their low methanol permeability and low cost compared to Nafion as well as good thermal stability. Unfortunately, these sulfonated membranes in which the sulfonic acid moieties are incorporated directly onto the backbones generally suffer from high water swelling and poor hydrolytic stability on increasing the degree of sulfonation [10] .…”