Synthesis and characterisation of sulfonic acid-containing ion exchange membranes based on hydrocarbon and fluorocarbon polymers

Material Aspects of the Design and Operation of Direct Borohydride Fuel Cells

“…The decrease in performance was partially attributed to membrane deterioration, possibly caused by the loss or poisoning of functional groups, de-cross-linking resulting in increased swelling, changes in IEC, fouling from precipitation of ions, and even physical breakdown, suggesting the necessity for further improvements in the stability of the 3541P membrane, particularly for applications at elevated temperatures. At 25°C (Figure 8b), the 3541P membrane exhibited better stability than Nafion ® 117, which was mainly attributed to the grafting process, which provided mechanically strong, insoluble, hydrophilic ion exchange membranes, at least at ambient temperature [19]. Efficient ion transport, due to their higher IEC values, occurring in the 3541P membrane could not be ruled out.…”

“…The 3541P membrane (wet thickness of 88.36 lm) consisted of an ethylene-tetrafluoroethylene (65%) backbone and polysulphonic acid (35%) grafting polymers, which has an ion exchange capacity (IEC) of 2.35 meq g -1 , a conductivity of 138.71 mS cm -1 , and a weight loss of 1.36% [18,19].…”

An empirical study into the effect of long term storage (−36±2°C) of electron-beamed ETFE on the properties of radiation-grafted alkaline anion-exchange membranes

“…Interestingly, H 0 for the 16 month (480 days) IEC is accepted when compared with 0 days cold storage (95% confidence level, unpaired 2-tailed t-test). These results show that EB-ETFE can be cold stored for over a year, as long as γ-ray irradiated ETFE films (Horsfall and Lovell, 2002) used to produce radiation-grafted proton-exchange membranes, and still produce viable AAEMs. However, electron beam facilities are commercially available (as they are used for sterilisation of medical equipment).…”

An anomalous peak observed in the electrochemistry of the platinum/perfluorosulfonic acid membrane interface

“…The electrolytic media used were 0.5 mol dm -3 aqueous sulfuric acid (Aristar grade) solution, 0.5 mol dm -3 aqueous perchloric acid (Aristar grade) solution, Nafion 117 and a hydrocarbon based sulfonic acid cationic-exchange membrane [17] (labelled 3542 in this paper). The Nafion membranes were cleaned prior to experiments using a standard cleaning procedure consisting of boiling in 3% hydrogen peroxide, followed by boiling in 0.5 mol dm -3 sulfuric acid.…”