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Updated: Sep 23, 2025
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Relating alkaline stability to the structure of quaternary phosphonium cations
Bingzi Zhang1, Hai Long2, Robert B Kaspar1
1Department of Chemical and Biomolecular Engineering, University of Delaware Newark DE 19716 USA yanys@udel.edu.
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.
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