Green Design of Renewable Dual-Curing Polymers with Self-Healing and Recyclable Networks for 3D Printing

This work presents a green design approach for a novel class of dual-curing, self-healing polymers derived from vegetable oils for additive manufacturing. The polymer network is constructed from methacrylated and epoxidized monomers derived through environmentally friendly transformations, allowing for UV-curing radical polymerization followed by thermal curing via acid–epoxy reactions. The resulting materials exhibit self-healing behavior, supporting thermal reprocessing and chemical recycling via transesterification. Designed for circularity, polymers containing the vegetable oil derivatives─methacrylated and epoxidized─reached a biobased content of up to 98% and a biobased carbon content above 77%, far exceeding industry standards. The materials also display alkaline hydrolytic degradation, aligning with end-of-life strategies under a circular economy model. Dual-curing systems achieved an epoxy conversion of over 90% and gel contents above 97%, resulting in stable polymer networks suitable for reprocessing. The formulations were successfully processed using 3D printing platforms, producing well-defined structures despite viscosities exceeding the ideal printability window. The system containing the maleinized/methacrylated grapeseed oil and epoxidized castor oil showed the most favorable behavior, with lower overcuring and the lowest critical energy (37 mJ cm– 2). Successful printing confirms the applicability of these systems.