Anion exchange membranes based on tetra-quaternized poly(arylene ether ketone)

Poly(arylene ether sulfone) bearing multiple benzyl-type quaternary ammonium pendants: preparation, stability and conductivity

“…To compare WUs among kinds of membranes with different IEC values, a more reasonable parameter, the number of absorbed water molecules per ionic group (l), is employed for both proton and hydroxide exchange membranes, 36,37 and calculated via the equation, l ¼ (10 Â WU)/(18 Â IEC). The present DFBDM-based PAES membranes give l values of 11-14 at 80 C, which are comparable to the l values of the reported PAES-based AEMs functionalized by imidazolium salt (6-74 at 60 C) 33,41 and by quaternary ammonium (7-115 at 80 C), 34,35,42 poly(arylene ether ketone)-based AEMs (3-38 at 80 C), 13,39,43 but smaller than that of the reported PPO-based AEMs (24 at 70 C). 28 It can be seen that the present uncrosslinked AEMs (QPAES(1/3) and QPAES(1/4)) have higher l values (12-14) than the reported membrane Q (l of 11) 36 due to its greater length and dense distribution of the pedant quaternary ammonium groups, which is in agreement with above WU.…”

“…[3][4][5] The AEM plays a key role in an AEMFC, such as conducting hydroxide ions from cathode to anode, as well as preventing fuel crossover between anode and cathode. To be suitable for AEMFC applications, AEMs should meet some fundamental requirements such as high hydroxide conductivity, low swelling degree, and high alkaline stability, 6-8 therefore a number of polymers bearing anion groups (quaternary ammonium, [9][10][11][12][13] imidazolium, [14][15][16] guanidinium, 17 and phosphonium groups 18,19 ) have been developed to act as AEMs, where the as-utilized polymers include poly(styrene), 20,21 poly(arylene ether), [22][23][24][25][26] poly (phenylene), 27,28 poly(phenylene oxide). 29,30 Among these AEMs, quaternized poly(styrene) based AEMs are commercially available.…”

Fabrication of N1-butyl substituted 4,5-dimethyl-imidazole based crosslinked anion exchange membranes for fuel cells

“…IEC value reects the xed ion concentration in AEMs and can reects the properties of AEMs to some extent. 25,41 The IEC values of M-BDIm-OH were obtained by the back titration method. As shown in Fig.…”

Densely quaternized anion exchange membranes synthesized from Ullmann coupling extension of ionic segments for vanadium redox flow batteries

“…[4]. These AEMs are usually flexible and robust, with tunable ion exchange capacities (IECs), water uptakes, and anion conductivities [25,26].…”