Iodination of sulphonated poly(ether ether ketone) through N-iodoimide electrophilic substitution of phenoxy beta-hydrogen

Abstract

Sulphonated poly(ether ether ketone) (SPEEK) exhibits excellent mechanical properties as a proton exchange membrane. However, its proton conductivity remains insufficient for practical applications. To address this limitation, a covalent incorporation of proton-conductive functional groups into the SPEEK matrix is proposed to establish continuous proton transport channels. Herein, through an iodination reaction of N-iodosuccinimide with SPEEK, we have successfully synthesised iodinated sulphonated poly(ether ether ketone) (I-SPEEK) with an iodination efficiency of 71.0% as confirmed by ion chromatography. This work proposes tentative reactivity positions and mechanistic hypotheses for the sulphonation of poly(ether ether ketone) and the subsequent iodination of SPEEK. Effective introduction of iodine is confirmed by Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Meanwhile, I-SPEEK serves as a precursor that provides grafting sites for hydrophilic groups (e.g. vinyl-silanes via the Heck reaction), offering a novel strategy for subsequent studies to introduce proton-conductive moieties.

Graphical abstract: Iodination of sulphonated poly(ether ether ketone) through N-iodoimide electrophilic substitution of phenoxy beta-hydrogen

Transparent peer review

To support increased transparency, we offer authors the option to publish the peer review history alongside their article.

View this article’s peer review history

Article information

Article type
Paper
Submitted
05 Jul 2025
Accepted
28 Aug 2025
First published
30 Aug 2025

New J. Chem., 2025, Advance Article

Iodination of sulphonated poly(ether ether ketone) through N-iodoimide electrophilic substitution of phenoxy beta-hydrogen

S. Yang, X. Gao, Y. Yu, Z. Zeng, J. Chen, W. Du, R. Liu, S. Li, B. Chen and C. Wu, New J. Chem., 2025, Advance Article , DOI: 10.1039/D5NJ02737C

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