Thionolactone as a Resin Additive to Prepare (Bio)degradable 3D Objects via VAT Photopolymerization

• Published in: Angewandte Chemie International Edition Vol. 61; no. 18; pp. e202117700 - n/a
• Main Authors: Gil, Noémie, Thomas, Constance, Mhanna, Rana, Mauriello, Jessica, Maury, Romain, Leuschel, Benjamin, Malval, Jean‐Pierre, Clément, Jean‐Louis, Gigmes, Didier, Lefay, Catherine, Soppera, Olivier, Guillaneuf, Yohann
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 25.04.2022; Wiley-VCH Verlag
• Edition: International ed. in English
• Subjects: 3D Printing; Bonding strength; Chemical Sciences; Composts; Degradability; Degradable Materials; Degradation; Lithography; Mechanical properties; Photopolymerization; Polymerization; Polymers; Printing, Three-Dimensional; Radical Ring-Opening Polymerization; Resins; Ring opening polymerization; Thionolactone; Three dimensional printing; 3D Printing; Degradable Materials; Radical Ring-Opening Polymerization; Thionolactone; Photopolymerization
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202117700

Three‐dimensional (3D) printing and especially VAT photopolymerization leads to cross‐linked materials with high thermal, chemical, and mechanical stability. Nevertheless, these properties are incompatible with requirements of degradability and re/upcyclability. We show here that thionolactone and in particular dibenzo[c,e]‐oxepane‐5‐thione (DOT) can be used as an additive (2 wt %) to acrylate‐based resins to introduce weak bonds into the network via a radical ring‐opening polymerization process. The low amount of additive makes it possible to modify the printability of the resin only slightly, keep its resolution intact, and maintain the mechanical properties of the 3D object. The resin with additive was used in UV microfabrication and two‐photon stereolithography setups and commercial 3D printers. The fabricated objects were shown to degrade in basic solvent as well in a homemade compost. The rate of degradation is nonetheless dependent on the size of the object. This feature was used to prepare 3D objects with support structures that could be easily solubilized. Three‐dimensional (3D) UV‐printing produces cross‐linked materials that are stable and non‐degradable. The introduction of a thionolactone dopant (2 wt % of dibenzo[c,e]‐oxepane‐5‐thione (DOT)) to acrylate‐based resins produced via radical ring‐opening polymerization confers (bio)degradability through the thioester units in the network. The resin was used in different setups, including commercial 3D printers, and the objects were shown to degrade in basic solution under mild conditions.