Novel cardo poly(arylene ether sulfone)s with pendant sulfonated aliphatic side chains for proton exchange membranes

Synthesis and properties of highly branched star-shaped sulfonated block polymers with sulfoalkyl pendant groups for use as proton exchange membranes

“…However, the many disadvantages of these materials, such as their high cost, high methanol permeability and loss of conductivity at high temperatures ( 480°C) [6], have limited their commercial applications. In recent years, many aromatic hydrocarbon polymers have been extensively explored because of their satisfactory thermal properties and electrochemical stability [7][8][9]. Among aromatic hydrocarbon polymeric PEMs, sulfonated poly(arylene ether)s (SPAEs) are considered one of the most promising candidates for PEMFC applications by virtue of their stable thermal properties and high solubility in organic solvents [2,[10][11][12].…”

“…In addition, the oxidative stability (420 min) of the branched polymers with pendant acid groups on the side chains was also improved compared with that of the corresponding branched polymer without pendant groups (281 min). This is attributed to the fact that in polymers [9,[25][26][27][28] with pendant acid groups on their side chains, the main polymer chain can be maintained in a hydrophobic environment. Thus, the chains initially separate into nanophases, which can reduce the probability of attack by water and peroxy radicals on the main chain, leading to excellent oxidative stability.…”

Proton-conducting membranes from poly(ether sulfone)s grafted with sulfoalkylamine

“…Gieselman and coworkers have demonstrated that amine groups in aramid poly(p-phenylene terephthalamide) (PPTA) could be sulfopropylated through direct attachment of aliphatic groups to the amine nitrogen with 1,3-propanesultone using NaH as a base [46]. Zhang and coworkers also prepared sulfonated poly(ether sulfone)s with one attached flexible sulfoalkyl group in each unit by a grafting reaction of 1,3-propanesultone or 1,4-butanesultone with an aminesubstituted polymer [38]. Applying similar methodology to the present work, Scheme 1 shows the grafting reaction of sulfobutyl groups onto A-PES-xx by nucleophilic ring opening reaction with 1,4-butanesultone.…”

“…This was demonstrated to be an effective approach in achieving good PEM performance; the membranes had good conductivityswelling behavior in the wet state due to the hydrophilic sulfonic acid groups being flexible and distant from the hydrophobic polymer main chain. Some of the membranes also exhibited clear nanophase-separated morphology with interconnected hydrophilic clusters [38][39][40][41][42][43]. However, most of these side-chain-type PEM had low IEC values and the proton conductivity under low humidity conditions required additional improvement [42,43].…”

The sulfonated poly(phenylene) membranes containing multi-phenylrings prepared by nickel catalyst

“…Generally, commercial membranes, Nafion 1 and Flemion 1 which are perfluorinated copolymer membranes, are used to PEM materials because they have good chemical, mechanical stability, and high proton conductivity [4][5][6]. However, the demerit of the perfluorosulfonic acid polymers, such as high methanol permeability and low operation temperature (<100 8C) disrupt their applications [7][8][9]. In recent years, researcher's interest about aromatic hydrocarbon polymer materials with degrees of sulfonation [10][11][12].…”