In Situ Photoresin Synthesis via Reactive Diluents for Vat Photopolymerization.

As climate change intensifies, there is a pressing demand for sustainable alternatives to fossil-derived photoresins in additive manufacturing. While biobased systems have been explored, many rely on hazardous solvents, limiting their environmental benefits. Here, we report a one-pot, purification-free strategy for synthesizing renewable, high-performance photoresins using furan-based monomers derived from lignocellulosic biomass. Furfuryl methacrylate and 4,4'-bismaleimidodiphenylmethane (BSM) were integrated into methacrylate networks via Diels-Alder (DA) chemistry, with 2-hydroxyethyl methacrylate (HEMA) enabling high conversion (93%) under optimized conditions. Mechanical testing revealed that UV postcuring enhanced tensile strength, whereas excessive UV or solvent exposure caused oligomer leaching. Thermal postcuring activated retro-DA reactions, improving mechanical robustness and shape memory performance. Comparative studies showed aromatic DA derivatives offered superior programmability, while aliphatic analogs provided higher renewable carbon content with stable printability. This scalable, solvent-free strategy establishes a green chemistry framework for sustainable, high-performance photoresins, advancing additive manufacturing toward circular economy objectives.