Development of a high-performance dual-curing Vitrimeric acrylate/epoxy system for 3D printing: Analysis of thermal effect and network evolution

Vat photopolymerization (VPP) 3D printing has gained significant attention for its ability to fabricate complex geometries with high resolution and excellent surface finish using relatively low-cost equipment. However, developing materials that combine mechanical robustness, geometric fidelity, and recyclability remains challenging. Here, we present a dual-curing vitrimeric acrylate/epoxy system that transitions from a highly deformable up to 80 % of strain in the intermediate state (ultimate tensile strength of 0.7 MPa) to a mechanically robust final state (ultimate tensile strength of 66 MPa) after thermal treatment. The system also supports effective repair via bonding protocols, recovering substantial mechanical integrity, thanks to the transesterification bond exchange. In spite of some shortcomings related to the irreversible changes in network structure upon thermal cycling, these results demonstrate a promising versatile platform for sustainable, durable, and repairable VPP components.