Cross-Linking-Induced Emission in Polymers

  • Author: Angewandte Chemie International Edition
  • Published Date: 18 January 2021
  • Source / Publisher: Angewandte Chemie International Edition/Wiley-VCH
  • Copyright: Wiley-VCH GmbH
thumbnail image: Cross-Linking-Induced Emission in Polymers

Polymer materials with tunable fluorescence are used, e.g., in biological imaging, sensing, or information storage. However, for cross-linked polymeric materials, it is difficult to regulate their emission behavior due to their insoluble and unmeltable nature. The development of cross-linked materials with dynamic bonds could help to solve this problem.

Yu Jiang, South-Central University for Nationalities, Wuhan, China, and Nikos Hadjichristidis, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia, have developed Diels–Alder (DA) polymer networks which consist of linear copolymers (chains pictured in blue) that contain furan groups (pictured in brown), i.e., copolymers of methyl-, decyl-, or lauryl methacrylate with furfuryl methacrylate. These polymer chains are crosslinked by dimaleimide‐substituted tetraphenylethene units (pictured in grey/green).


The crosslinked-DA polymer networks show strong emission. Usually, dimaleimide‐substituted tetraphenylethene is non‐emissive due to a photo‐induced electron transfer (PET) between the maleimide and tetraphenylethene groups. In the cross-linked network, this PET process is prevented and the intramolecular rotation of the tetraphenylethene molecules is restricted, which turns on the emission.

The cross-linking-induced emission behavior can be adjusted via a reversible DA/retro-DA reaction, which can be influenced by the temperature. At high temperatures, the retro‐DA reaction is dominant, and the fluorescence is quenched by opening the cross-links. In contrast, at low temperatures, the emission recovers as the DA reaction takes over. Cross-linking-induced emission provides a new strategy for regulating the fluorescence of polymer materials. According to the researchers, this could lead to applications, e.g., in smart coatings or information security.



Article Views: 2158

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from, please contact us first for permission. more

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH