Application of RAFT in 3D Printing: Where Are the Future Opportunities?

Research into 3D printing using reversible addition–fragmentation chain transfer (RAFT) polymerization has garnered interest since it was first reported in 2019. This technique was initially developed to expand the scope of light-based 3D printing technologies by producing materials that can be modified postprinting, termed "living" 3D printing. The livingness can be achieved by incorporating reactivatable RAFT functionalities within the polymer networks, enabling 3D materials to be modified after printing. As the field of RAFT-mediated 3D printing has progressed, further studies have revealed its applications in advanced materials. These include spatially resolved surface functionalization and patterning, self-healing, welding, and nano- and microscale structuring of 3D polymers. Additionally, RAFT-mediated 3D printing enables the production of scaffolds with controlled interconnected channel-pore architecture, suitable for customized drug delivery. This Perspective provides a review of the chemical mechanisms employed in RAFT-mediated 3D printing and highlights the advanced materials manufactured through this technology. Potential research directions in this field are also discussed and organized for future investigation.