DLP 3D printing of biobased, soft and degradable thiol-ene networks from cardanol-based polyesters

• A cost-effective and eco-friendly synthesis route cardanol-based diol. • A fully biobased cardanol-based polyester as photo-printable biobased resin. • DLP 3D printing of soft and degradable thiol-ene networks from cardanol-based polyesters. Cardanol is an attractive biobased building block derived from cashew nut shells, offering a sustainable alternative to fossil-based substances without competing with the food industry. Here, we introduce an approach for Digital Light Processing (DLP) 3D printing soft and degradable thiol-ene networks from cardanol-based polyesters. A cost-effective and eco-friendly synthesis of a cardanol-based diol was first developed using glycerol carbonate generated in situ , followed by two-step melt polycondensation with succinic acid to obtain a fully biobased polyester with reactive alkene groups. Cardanol-based resins were then DLP 3D printed via thiol-ene chemistry using a trifunctional thiol crosslinker. The printed networks exhibited soft mechanical behavior with high thermal stability, a low T g around −20 °C, and a Young modulus between 0.2 and 2 MPa. Their softness enabled the fabrication of complex structures, including highly deformable re-entrant auxetic architectures. Hydrolytic degradation studies performed in alkaline conditions showed complete degradation within two days, demonstrating the potential of cardanol-based networks for scalable and sustainable applications.