H-bonds and metal-ligand coordination-enabled manufacture of palm oil-based thermoplastic elastomers by photocuring 3D printing

Thermoplastic elastomers exhibit high softness, stretchability, recoverability, and reprocessibility, but their manufacture requires high cost and long processing time. Photocuring 3D printing is a remedial processing method as it enables rapid fabrication at room temperature. However, it is difficult to print thermoplastic elastomers by photocuring 3D printing because the generated linear polymers easily dissolve in liquid precursors during printing. Herein, stretchable, self-healing, and renewable palm oil (PO)-based elastomers were prepared from UV-responsive vinyl PO monomers via photocuring 3D printing. Fast solid-liquid separation was achieved via hydrogen bonds and Zn 2+ -ligand coordination (non-covalent crosslinking) to slow down the dissolution of crosslinked polymers in the monomer liquid . The non-covalent bonds endowed the elastomers with high tensile strength (~4.2 MPa) and elongation at break (~851%). Additionally, the elastomers are mainly prepared from biobased, renewable, and low-cost PO feedstocks . Most importantly, the dual dynamic crosslinked network resulted in superior stress relaxation, shape programming, and self-healing behavior of the elastomers. The method described may enhance the application scope of thermoplastic elastomers and 3D printing.