title: Triazolinediones enable ultrafast and reversible click chemistry for the design of dynamic polymer systems.
abstract: With its focus on synthetic reactions that are highly specific and reliable, 'click' chemistry has become a valuable tool for many scientific research areas and applications. Combining the modular, covalently bonded nature of click-chemistry linkages with an ability to reverse these linkages and reuse the constituent reactants in another click reaction, however, is a feature that is not found in most click reactions. Here we show that triazolinedione compounds can be used in click-chemistry applications. We present examples of simple and ultrafast macromolecular functionalization, polymer-polymer linking and polymer crosslinking under ambient conditions without the need for a catalyst. Moreover, when triazolinediones are combined with indole reaction partners, the reverse reaction can also be induced at elevated temperatures, and the triazolinedione reacted with a different reaction partner, reversibly or irreversibly dependent on its exact nature. We have used this 'transclick' reaction to introduce thermoreversible links into polyurethane and polymethacrylate materials, which allows dynamic polymer-network healing, reshaping and recycling.
authors.affiliation: Department of Organic Chemistry, Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
authors.forename: Stijn
authors.initials: S
authors.lastname: Billiet
authors.affiliation: Department of Organic Chemistry, Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
authors.forename: Kevin
authors.initials: K
authors.lastname: De Bruycker
authors.affiliation: Department of Organic Chemistry, Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
authors.forename: Frank
authors.initials: F
authors.lastname: Driessen
authors.affiliation: Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde, Belgium.
authors.forename: Hannelore
authors.initials: H
authors.lastname: Goossens
authors.affiliation: Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde, Belgium.
authors.forename: Veronique
authors.initials: V
authors.lastname: Van Speybroeck
authors.affiliation: Department of Organic Chemistry, Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
authors.forename: Johan M
authors.initials: JM
authors.lastname: Winne
authors.affiliation: Department of Organic Chemistry, Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent, Belgium.
authors.forename: Filip E
authors.initials: FE
authors.lastname: Du Prez