Ternary formulations of bio-based grapeseed oil-based monomers for 3D printing: Effect of thiol-ene reaction on acrylic radical photopolymerization

The development of new renewable resin formulation for VAT 3D printing is one of the most actively researched topics in chemistry and materials science. In this sense, a good balance of sustainability and final properties should be developed. Therefore, this work aims to use grapeseed oil-GSO, acrylated seed oil-AGSO, and Trimethylolpropane tris(3-mercapto propionate) – 3SH as monomers for new printable formulations. These formulations were investigated to understand the types of reactions that can occur during photopolymerization. Therefore, two reactions can occur depending on the system: thiol-ene polymerization (TEP) and free radical polymerization (FRP). All formulations showed conversion values superior to 80% and are feasible to be applied in VAT 3D printing to print complex structures. Moreover, formulations containing a higher quantity of GSO-3SH presented biobased carbon content superior to 72% and gel content higher than 99%. Last, the amount of the TE part (GSO-3SH) affects the glass transition temperature, mechanical properties (toughness, stress, strain), and hydrophobicity. Therefore, materials with different stress, strain, and toughness can be designed using various concentrations of each monomer.