Issue 16, 2022

Benzaldehyde-mediated selective aerobic polyethylene functionalisation with isolated backbone ketones

Abstract

Post-synthetic functionalisation of commodity polymers such as polyethylene (PE) is an increasingly important strategy for giving waste plastics new ‘lease-of-lives’ as functional polymers. In particular, installing oxygenated functional groups such as alcohols and ketones is valuable due to their chemical versatility for further chemical modifications. However, this is especially challenging for PE due to its unreactive nature, and often requires hazardous and environmentally damaging chlorinated solvents owing to PE's excellent solvent resistance. Herein, we demonstrate a highly selective method to install isolated carbonyl groups on PE using only benzaldehyde and O2 as a terminal oxidant, without the need for stoichiometric organic oxidants or any hazardous organic solvents. This process relies on the aerobic auto-oxidation of benzaldehyde to benzoic acid, generating reactive radical intermediates in the process that are responsible for both C–H activation and exclusive carbonyl formation. Our method is compatible with copper(II) oxidation catalysts to enhance the extent of PE oxidation, and can also minimise the waste produced as the benzoic acid side product can be easily isolated and reused for different applications. The versatility of carbonyl-containing PEs for further chemical derivatisation offers many exciting options for transforming waste PE into diverse polymeric materials for a materials circular economy.

Graphical abstract: Benzaldehyde-mediated selective aerobic polyethylene functionalisation with isolated backbone ketones

Supplementary files

Article information

Article type
Paper
Submitted
05 Jul 2022
Accepted
20 Jul 2022
First published
26 Jul 2022
This article is Open Access
Creative Commons BY-NC license

Green Chem., 2022,24, 6287-6294

Benzaldehyde-mediated selective aerobic polyethylene functionalisation with isolated backbone ketones

J. Y. Q. Teo, C. W. S. Yeung, T. T. Y. Tan, W. W. Loh, X. J. Loh and J. Y. C. Lim, Green Chem., 2022, 24, 6287 DOI: 10.1039/D2GC02502G

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, 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 commercial 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