Issue 7, 2022

Tuning hydrophobic composition in terpolymer-based anion exchange membranes to balance conductivity and stability

Abstract

We designed and synthesized novel terpolymer-based anion conductive polymers, where the effect of hydrophobic composition on the membrane properties was investigated in detail. Precursor terpolymers were first prepared from 2,2-bis(4-chlorophenyl)hexafluoropropane (BAF), 1,6-bis(3-chlorophenyl)perfluorohexane (PAF), and 2,7-dichloro-9,9-bis[6′-(N,N-dimethylamino)hexyl]fluorene via Ni(0)-promoted polycondensation reaction. The following quaternization reaction with dimethyl sulfate was successful to obtain five terpolymers, QBPA with different PAF/(BAF + PAF) compositions and supposed chemical structures. QBPA provided thin and bendable membranes by solution casting. TEM images suggested that the membranes exhibited a phase-separated morphology similar to those of the corresponding parent copolymer membranes. SAXS profiles indicated that QBPA-4 containing 83 mol% PAF exhibited the most distinct periodic structure based on the hydrophobic component. The hydroxide ion conductivity of the membranes showed a volcano-type dependence on the hydrophobic composition, and the highest conductivity (161 mS cm−1) was achieved with the QBPA-1 membrane at 80 °C. Taking also the other properties into account, QBPA-1 and QBPA-5 containing 17 mol% PAF seemed the best-balanced membranes. An alkaline fuel cell using the QBPA-1 membrane achieved a maximum power density of 273 mW cm−2, exceeding that using the copolymer BAF-QAF membrane (185 mW cm−2).

Graphical abstract: Tuning hydrophobic composition in terpolymer-based anion exchange membranes to balance conductivity and stability

Supplementary files

Article information

Article type
Paper
Submitted
14 Feb 2022
Accepted
30 Mar 2022
First published
30 Mar 2022

Mol. Syst. Des. Eng., 2022,7, 798-808

Author version available

Tuning hydrophobic composition in terpolymer-based anion exchange membranes to balance conductivity and stability

Y. Ozawa, Y. Shirase, K. Otsuji and K. Miyatake, Mol. Syst. Des. Eng., 2022, 7, 798 DOI: 10.1039/D2ME00027J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements