Tunable Photothermal Actuation Enabled by Photoswitching of Donor–Acceptor Stenhouse Adducts

Abstract

We report a visible light-responsive bilayer actuator driven by the photothermal properties of a unique molecular photoswitch: donor–acceptor Stenhouse adduct (DASA). We demonstrate a synthetic platform to chemically conjugate DASA to a load-bearing poly(hexyl methacrylate) (PHMA) matrix via Diels–Alder click chemistry that enables access to stimuli-responsive materials on scale. By taking advantage of the negative photochromism and switching kinetics of DASA, we can tune the thermal expansion and actuation performance of DASA–PHMA under constant light intensity. This extends the capabilities of currently available responsive soft actuators for which mechanical response is determined exclusively by light intensity and enables the use of abundant broadband light sources to trigger tunable responses. We demonstrate actuation performance using a visible light-powered cantilever capable of lifting weight against gravity as well as a simple crawler. These results add a new strategy to the toolbox of tunable photothermal actuation by using the molecular photoswitch DASA.

ICB Affiliated Authors

Authors
Jaejun Lee, Miranda M. Sroda, Younghoon Kwon, Sara El-Arid, Serena Seshadri, Luke F. Gockowski, Elliot W. Hawkes, Megan T. Valentine, and Javier Read de Alaniz
Date
Type
Peer-Reviewed Article
Journal
ACS Applied Materials & Interfaces
Volume
12
Number
48
Pages
54075-54082
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