Strategic design and functional evaluation of oligomer components in vat photopolymerization 3D printing of alumina ceramics

Oligomers are crucial components in photosensitive resins but remain underutilized in vat photopolymerization (VPP) ceramic 3D printing due to the low-viscosity requirements of ceramic slurries. This study reappraises their role by evaluating five representative oligomers—including polyurethane acrylates (PUA-1, PUA-2, PUA-3) and epoxy acrylates (EA-1, EA-2)—for their effects on slurry viscosity, curing kinetics, and debinding behavior. Incorporating oligomers significantly enhanced curing depth. Specifically, the EA-1 formulation doubled penetration depth compared to the control. Simultaneously, PUA-2, EA-1, and EA-2 significantly enhanced monomer conversion rates, effectively modulating polymerization dynamics. The debinding process was also optimized, typically raising the peak decomposition temperature of the green body with EA-1 from 257 °C to 313 °C. While oligomers increased viscosity and slightly reduced flexural strength, these effects are mitigable through rational oligomer design. This work demonstrates that oligomers can be strategically engineered to optimize the ceramic VPP process, providing a framework for advanced resin formulation.