Hydroxide Conducting Membranes with Quaternary Ammonium Cations Tethered to Poly(arylene alkylene)s via Flexible Phenylpropyl Spacers
Chen, Si LU ; Pan, Dong LU ; Gong, Haiyue LU and Jannasch, Patric LU
(2024)
In Chemistry of Materials
36(1).
p.371-381
- Abstract
- Durable and high-performing anion exchange membranes (AEMs) are central components in alkaline water electrolyzers and fuel cells. Here, we have pursued a synthetic strategy where heteroatom-free polymer backbones are functionalized with alkali-stable dimethyl piperidinium (DMP) cations via flexible spacers. We achieved this design by synthesizing a trifluorobenzophenone monomer carrying a piperidine group in the 4-position via a straightforward Friedel–Crafts acylation of 4-(3-phenylpropyl)piperidine. Polyhydroxyalkylation of this ketone and p-terphenyl, followed by N-methylation, generated a DMP-functionalized poly(p-terphenyl alkylene) (PpT-DMP) with excellent alkaline stability, e.g., less than 7% ionic loss after... (More)
- Durable and high-performing anion exchange membranes (AEMs) are central components in alkaline water electrolyzers and fuel cells. Here, we have pursued a synthetic strategy where heteroatom-free polymer backbones are functionalized with alkali-stable dimethyl piperidinium (DMP) cations via flexible spacers. We achieved this design by synthesizing a trifluorobenzophenone monomer carrying a piperidine group in the 4-position via a straightforward Friedel–Crafts acylation of 4-(3-phenylpropyl)piperidine. Polyhydroxyalkylation of this ketone and p-terphenyl, followed by N-methylation, generated a DMP-functionalized poly(p-terphenyl alkylene) (PpT-DMP) with excellent alkaline stability, e.g., less than 7% ionic loss after treatment in 7 M aq. NaOH solution at 90 °C for 240 h. A high OH– conductivity, up to 104 mS cm–1 at 80 °C, was reached at an ion exchange capacity (IEC) of 1.79 mequiv g–1 and 53% water uptake. Atomic force microscopy (AFM) revealed a distinct microphase separation into ionic and nonionic nano-domains. The Friedel–Crafts acylation method proved very versatile and was also employed to synthesize a bromoalkylated trifluorobenzophenone monomer from 1-bromo-3-phenylpropane, which gives access to a diverse range of AEM materials. Poly(arylene alkylene)s based on this monomer and p-terphenyl and dimethylfluorene, respectively, were prepared in polyhydroxyalkylation and subsequently functionalized with alkyltrimethylammonium and N-methyl-N-alkyl piperidinium cations, respectively. Especially, AEMs based on the former material showed a remarkably high conductivity, up to 175 mS cm–1 at 80 °C. In summary, we present a straightforward approach to synthesize trifluorobenzophenone monomers substituted with 4-propylpiperidine and propyl bromide groups, respectively, which enables the preparation of various heteroatom-free poly(arylene alkylene)s tethered with alkali-stable cations for high-performance AEMs. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/cd7ac47d-e7f5-43a3-9683-3d17c95e744f
- author
- Chen, Si
LU
; Pan, Dong
LU
; Gong, Haiyue
LU
and Jannasch, Patric
LU
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Chemistry of Materials
- volume
- 36
- issue
- 1
- pages
- 11 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85181554269
- ISSN
- 0897-4756
- DOI
- 10.1021/acs.chemmater.3c02247
- language
- English
- LU publication?
- yes
- id
- cd7ac47d-e7f5-43a3-9683-3d17c95e744f
- date added to LUP
- 2023-08-30 22:34:41
- date last changed
- 2024-01-31 14:35:49
@article{cd7ac47d-e7f5-43a3-9683-3d17c95e744f,
abstract = {{Durable and high-performing anion exchange membranes (AEMs) are central components in alkaline water electrolyzers and fuel cells. Here, we have pursued a synthetic strategy where heteroatom-free polymer backbones are functionalized with alkali-stable dimethyl piperidinium (DMP) cations via flexible spacers. We achieved this design by synthesizing a trifluorobenzophenone monomer carrying a piperidine group in the 4-position via a straightforward Friedel–Crafts acylation of 4-(3-phenylpropyl)piperidine. Polyhydroxyalkylation of this ketone and p-terphenyl, followed by <i>N</i>-methylation, generated a DMP-functionalized poly(<i>p</i>-terphenyl alkylene) (P<i>p</i>T-DMP) with excellent alkaline stability, e.g., less than 7% ionic loss after treatment in 7 M aq. NaOH solution at 90 °C for 240 h. A high OH<sup>–</sup> conductivity, up to 104 mS cm<sup>–1</sup> at 80 °C, was reached at an ion exchange capacity (IEC) of 1.79 mequiv g<sup>–1</sup> and 53% water uptake. Atomic force microscopy (AFM) revealed a distinct microphase separation into ionic and nonionic nano-domains. The Friedel–Crafts acylation method proved very versatile and was also employed to synthesize a bromoalkylated trifluorobenzophenone monomer from 1-bromo-3-phenylpropane, which gives access to a diverse range of AEM materials. Poly(arylene alkylene)s based on this monomer and p-terphenyl and dimethylfluorene, respectively, were prepared in polyhydroxyalkylation and subsequently functionalized with alkyltrimethylammonium and <i>N</i>-methyl-<i>N</i>-alkyl piperidinium cations, respectively. Especially, AEMs based on the former material showed a remarkably high conductivity, up to 175 mS cm<sup>–1</sup> at 80 °C. In summary, we present a straightforward approach to synthesize trifluorobenzophenone monomers substituted with 4-propylpiperidine and propyl bromide groups, respectively, which enables the preparation of various heteroatom-free poly(arylene alkylene)s tethered with alkali-stable cations for high-performance AEMs.}},
author = {{Chen, Si and Pan, Dong and Gong, Haiyue and Jannasch, Patric}},
issn = {{0897-4756}},
language = {{eng}},
number = {{1}},
pages = {{371--381}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Chemistry of Materials}},
title = {{Hydroxide Conducting Membranes with Quaternary Ammonium Cations Tethered to Poly(arylene alkylene)s via Flexible Phenylpropyl Spacers}},
url = {{http://dx.doi.org/10.1021/acs.chemmater.3c02247}},
doi = {{10.1021/acs.chemmater.3c02247}},
volume = {{36}},
year = {{2024}},
}