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Synthetic approaches for advanced multi-block anion exchange membranes.

ABSTRACT: Despite our ability to post-functionalize poly(arylene ether sulfone) multi-block copolymers by rapid chloromethylation, bromination, or acylation, with degrees of functionalization that exceeded 70% in a few hours, materials formed during attempts to prepare fully post-functionalized multi-block copolymers are poorly soluble due to undesired side reactions, such as crosslinking or di-bromination. In particular, clustered reactive sites in multi-block copolymers increase the chance of self-reactions between polymer backbones, resulting in the formation of by-products. On the other hand, the authentic multi-block copolymer with good solubility and high molecular weight was successfully synthesized using functionalized monomers. Despite its low ion-exchange capacity, the resulting multi-block copolymer outperformed the commercial FAA-3-30 membrane in terms of anion conductivity, even under low relative humidity conditions.

SUBMITTER: Shin D

PROVIDER: S-EPMC9065993 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Synthetic approaches for advanced multi-block anion exchange membranes.

Shin Dongwon D Nugraha Adam F AF Wijaya Farid F Lee Sojeong S Kim Eunyoung E Choi Jieun J Kim Hyoung-Juhn HJ Bae Byungchan B

RSC advances 20190705 37

Despite our ability to post-functionalize poly(arylene ether sulfone) multi-block copolymers by rapid chloromethylation, bromination, or acylation, with degrees of functionalization that exceeded 70% in a few hours, materials formed during attempts to prepare fully post-functionalized multi-block copolymers are poorly soluble due to undesired side reactions, such as crosslinking or di-bromination. In particular, clustered reactive sites in multi-block copolymers increase the chance of self-react ...[more]

PMID: 35521315

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