Fabrication and characterization of light-curing soybean oil-based epoxy resin applied for LCD additive manufacturing

In this work, we developed a photocurable vegetable oil-based resin with suitable curing properties for use in 3D printing. The acrylated epoxidized soybean oil (AESO), which was synthesized by the catalytic ring-opening reaction of the epoxidized soybean oil (ESO) and acrylic acid (AA), replaced the oligomer in conventional light-curing petroleum-based resins. In order to optimize the various properties of the soybean oil-based epoxy resin, the performance parameters of the resin were analyzed by numerical simulation. It was also combined with the parameters of the printing equipment to better guide the 3D printing process of the resin. The results showed that the esterification rate of acrylic acid (AA) with epoxidized soybean oil (ESO) was higher than that of methacrylic acid (MAA) during the arylation of epoxidized soybean oil (ESO), and AESO had moderate viscosity and was suitable as an oligomer for 3D printing. When the diluent of the oligomer has an ACMO to HDDA ratio of 3:2, the cured parts exhibit the optimum mechanical properties, hydrophobic properties, and thermal stability. All properties of the resins were further improved and giving the formulation the best 3D printing performance when 10% of epoxy resin E44 was added to the soybean oil-based epoxy resin. In addition, the numerical simulations indicate that this soybean oil-based epoxy resin formulation has the highest printing efficiency when the single layer thickness of the cured layer is set to 0.2 mm with the exposure time of 4 s, where the wavelength of UV is 405 nm and the light intensity is 40 W/m2. In conclusion, the light-curing resin developed through the soybean oil-based epoxy resin exhibits excellent performance in all aspects. The optimal printing process was also derived by combining the results obtained from numerical simulations of the resin performance parameters with the device parameters, which significantly improved the efficiency of the 3D printing with the fabricated soybean oil-based epoxy resin, making it has great application potential for the biomedical materials.