Transimination reactions are highly effective dynamic covalent reactions to enable reprocessability in thermosets, as they can undergo exchange without the need for catalysts, by exposing the materials to external stimuli such as heat. In this work, a series of five biobased vanillin-derived resin formulations consisting of vanillin acrylate with vanillin methacrylate-functionalized Jeffamines were synthesized and 3D-printed using digital light projection (DLP). The resulting thermosets displayed a range of mechanical properties (Young’s modulus 2.05–332 MPa), which allow for an array of applications. The materials we obtained have self-healing abilities, which were characterized by scratch healing tests. Additionally, dynamic transimination reactions enable these thermosets to be reprocessed when thermally treated above their glass transition temperatures under high pressures using a hot press. Due to the simple synthetic procedures and the readily available commercial Jeffamines, these materials will aid in promoting a shift to materials with predominantly biobased content and help drift away from polymers made from non-renewable resources.

3D printing technologies can address many sustainability aspects of creating new materials, such as reduced waste and on demand production, which reduces the carbon footprint of transport and storage. Additionally,...

Transimination reactions are highly effective dynamic covalent reactions to enable reprocessability in thermosets, as they can undergo exchange without the need for catalysts, by exposing the materials to external stimuli such as heat. In this work, a series of five biobased vanillin derived resin formulations consisting of vanillin acrylate with vanillin methacrylate functionalized Jeffamines® were synthesized, and 3D printed using digital light projection (DLP). The resulting thermosets produced, displayed a range of mechanical properties (Young’s modulus 2.05 – 332 MPa) which allow for an array of applications. The materials we obtained have self-healing abilities which were characterized by scratch healing tests. Additionally, dynamic transimination reactions enable these thermosets to be reprocessed when thermally treated above their glass transition temperatures under high pressures using a hot-press. Due to the simple synthetic procedures and the readily available commercial Jeffamines®, these materials will aid in promoting a shift to materials with predominantly biobased content and help drift away from polymers made from non-renewable resources.

3D printing technologies can address many sustainability aspects of creating new materials, such as reduced waste and on demand production, which reduces the carbon footprint of transport and storage. Additionally, creating bio-based resins for 3D printing is a viable way of improving the sustainability of polymeric materials. Coupled with this, by using dynamic covalent chemistry (DCC), we can provide materials with smart properties like self-healing or reprocessability to either extend their usable lifetime or provide an alternative to the materials ending up in a landfill. Here, we report a series of completely bio-based aromatic resins for digital light projection (DLP) printing. By incorporating β-hydroxyesters and a zinc catalyst, the polymer networks can participate in transesterification reactions to provide self-healing capabilities or reprocessability. The self-healing abilities of these materials were characterized using optical microscopy, and the reprocessability using a hot-press. Additionally, by subjecting the printed thermosets to thermal annealing, considerable changes in the mechanical performance were observed leading to more than a 2000% increase in the Young’s modulus. The thermal behavior after annealing was also studied and a discussion on the effect of the structural differences between the aromatic monomers is proposed. These resin formulations address two of the key goals of sustainable materials: using renewable resources and obtaining recyclable materials while remaining competitive through their mechanical performance and compatibility with 3D printing technologies.