title: Conditional repair by locally switching the thermal healing capability of dynamic covalent polymers with light.
abstract: Healable materials could play an important role in reducing the environmental footprint of our modern technological society through extending the life cycles of consumer products and constructions. However, as most healing processes are carried out by heat alone, the ability to heal damage generally kills the parent material's thermal and mechanical properties. Here we present a dynamic covalent polymer network whose thermal healing ability can be switched 'on' and 'off' on demand by light, thereby providing local control over repair while retaining the advantageous macroscopic properties of static polymer networks. We employ a photoswitchable furan-based crosslinker, which reacts with short and mobile maleimide-substituted poly(lauryl methacrylate) chains forming strong covalent bonds while simultaneously allowing the reversible, spatiotemporally resolved control over thermally induced de- and re-crosslinking. We reason that our system can be adapted to more complex materials and has the potential to impact applications in responsive coatings, photolithography and microfabrication.
authors.affiliation: Department of Chemistry &IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor Straße 2, 12489 Berlin, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Fuhrmann
authors.affiliation: Department of Chemistry &IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor Straße 2, 12489 Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Göstl
authors.affiliation: Department of Chemistry &IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor Straße 2, 12489 Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Wendt
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany.|Jena Center for Soft Matter, Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Kötteritzsch
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany.|Jena Center for Soft Matter, Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany.
authors.forename: Martin D
authors.initials: MD
authors.lastname: Hager
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743 Jena, Germany.|Jena Center for Soft Matter, Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany.
authors.forename: Ulrich S
authors.initials: US
authors.lastname: Schubert
authors.affiliation: Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Brademann-Jock
authors.affiliation: Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
authors.forename: Andreas F
authors.initials: AF
authors.lastname: Thünemann
authors.affiliation: Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Department Active Polymers, Helmholtz-Zentrum Geesthacht, Kantstraße 55, 14513 Teltow, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Nöchel
authors.affiliation: Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Department Active Polymers, Helmholtz-Zentrum Geesthacht, Kantstraße 55, 14513 Teltow, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Behl
authors.affiliation: Department of Chemistry &IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor Straße 2, 12489 Berlin, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hecht