Design of acrylated epoxidized soybean oil biobased photo-curable formulations for 3D printing

In recent decades, the significance of developing polymeric materials derived from renewable bio-based sources has grown due to the pressing environmental concerns facing our planet. Moreover, the diminishing availability of oil, the primary carbon resource for polymer production, led to the research of alternative sources with low environmental impact. From this perspective, vegetable oils (VO) have emerged as an interesting option due to their abundant presence and cost-effectiveness, along with the presence of numerous reactive groups. Among these, soybean oil stands out as one of the most widely used options, thanks to its potential for functionalization through epoxidation and subsequent acrylation, resulting in acrylate epoxidized soybean oil (AESO). In this study AESO was employed as a primary raw material for Digital Light Processing (DLP) because of its photocurable nature. Because of its high viscosity, four monofunctional reactive diluents, namely lauryl acrylate (LA), lauryl methacrylate (LMA), isobornyl acrylate (IBOA) and isorbornyl methacrylate (IBOMA), were incorporated in different weight percentages. Reactivity and rheological properties of these formulations were investigated. Subsequently, formulations with viscosities suitable for the DLP process were employed to 3D print objects. These printed samples were then subjected to mechanical and thermo-mechanical analyses. Moreover, more complex shaped objects were printed to evaluate the precision of the printing process using these formulations.