Polymer brushes represent a versatile toolbox for altering surface chemistry, resulting in new properties, e.g. improved adhesion, anti-fogging or anti-fouling. However, polymer brushes are often attached permanently, making substrates available for only one specific functionality. To introduce detachable poly(methyl methacrylate) brushes, we exploit that catechol has a redox-dependent affinity for hard metal ions such as Al<sup>3+</sup>. In practice, electrochemically responsive metal catecholate attachments are covalently immobilized on glassy carbon substrates, followed by the introduction of a radical initiator, enabling subsequent polymer brush synthesis through controlled radical polymerization. X-ray photoelectron spectroscopy (XPS) measurements reveal that the density of polymerization initiators is pH dependent, directly influencing the polymer brush thickness.<br/>To illustrate the detachment concept, a 30 s electrochemical pulse is applied, oxidizing the catechol to quinone, resulting in diminished coordination affinity for the metal ions. Ultimately, this causes dissociation of the metal-catecholate complexes (Figure 1), resulting in detachment of the polymer brushes, confirmed by absence of signals in infrared reflection absorption spectroscopy and XPS, and by a change in film thickness from 54 to 5 nm measured by ellipsometry.

Use of metal-catecholates to accomplish stimuli-responsive detachment of polymer brushes

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.