Dynamic covalent chemistry enables advanced 3D printing: principles, processability, and functional evolution.

Additive manufacturing (3D printing) has emerged as a transformative technology for the high-precision fabrication of complex geometric structures. However, conventional printable polymers face significant bottlenecks throughout their lifecycle, including weak interlayer bonding during processing, insufficient functionality and tunability during service, and recycling difficulties at the end of life. Incorporating dynamic covalent chemistry (DCC) into 3D printing systems offers a solution to these challenges. This review comprehensively summarizes recent research progress on the impact of DCC on 3D printing. It begins by outlining the fundamental molecular mechanisms of various DCCs suitable for additive manufacturing. Subsequently, from a processing perspective, it discusses how DCC synergistically modulates rheological behavior and network strength in photocuring or extrusion-based printing. From the perspective of service and performance, it details the functional enhancements conferred upon components by dynamic networks, such as self-healing, modular assembly, and programmable 4D shape reconfiguration. Finally, from an end-of-life perspective, it summarizes sustainable management strategies, including structural remolding and re-printing. By highlighting frontier directions such as smart-gated dynamic networks and AI-assisted design, this review aims to provide a forward-looking research perspective for the regulation and development of next-generation functional dynamic polymers in advanced manufacturing.