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Relating alkaline stability to the structure of quaternary phosphonium cations.

ABSTRACT: Alkali-stable quaternary phosphonium (QP) is a type of cationic group for hydroxide exchange membranes (HEMs). To elucidate the relationship between structure and alkaline stability, we investigated the kinetics and degradation mechanism of a series of QP cations by both experiment and computation, and established a semi-empirical formula based on the Taft equation to directly estimate alkaline stability of QP cations from the ³¹P NMR chemical shift δ and the steric substituent constant E _s, facilitating the search for QP cations with improved alkaline stability.

SUBMITTER: Zhang B

PROVIDER: S-EPMC9086583 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Relating alkaline stability to the structure of quaternary phosphonium cations.

Zhang Bingzi B Long Hai H Kaspar Robert B RB Wang Junhua J Gu Shuang S Zhuang Zhongbin Z Pivovar Bryan B Yan Yushan Y

RSC advances 20180725 47

Alkali-stable quaternary phosphonium (QP) is a type of cationic group for hydroxide exchange membranes (HEMs). To elucidate the relationship between structure and alkaline stability, we investigated the kinetics and degradation mechanism of a series of QP cations by both experiment and computation, and established a semi-empirical formula based on the Taft equation to directly estimate alkaline stability of QP cations from the <sup>31</sup>P NMR chemical shift <i>δ</i> and the steric substituent ...[more]

PMID: 35547560

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