Through the processes of epoxidation and methacrylation, the triglyceride structure remained intact, as shown by the peak at 4-4.5 ppm. From the NMR, the MEMO obtained with 1 % of TPP had a Degree of Modification (DoM) of 1.2 ± 0.1. Instead, using 2% of TPP, the obtained DoM was 2.2 ± 0.2, where most of the epoxide groups were converted into methacrylates. Resin formulation. The MEMO obtained with 1% and 2% of TPP from the reactions descried above was used to formulate a library of biobased methacrylate photoresins by mixing it with a diluent and a photoinitiator to obtain curable resins. As diluent, we used the Isobornyl Methacrylate (IBOMA), a molecule that has 70% of C from biobased resources , and phenylbis(2,4,6trimethylbenzoyl)phosphine oxide (BAPO) as the photoinitiator. Both components are widely used in the literature to formulate photocurable resins . We used different percentages of MEMO and diluent to analyze the influence of the diluent on the curing efficiency and the mechanical properties of the final product (Table ). The resins were formulated using the MEMO with higher DoM (2% of TPP) and lower DoM (1% TPP) to evaluate the effects of the number of functional groups on the cured product. Five different resin compositions were prepared for both the MEMO with 1% of TPP (MEMO_1) and 2% of TPP (MEMO_2), starting from 100% of the oil in the absence of diluent, and gradually increasing the amount of IBOMA until 60%. For all the formulations, 2% of photoinitiator was added to the mixture. The resulting resins were used immediately for mechanical and 3D printing tests. However, to evaluate the stability of the resin over an extended period of time, a sample of the MEMO_2_60 resin was stored at 4°C in the fridge for one month, covered by aluminum foil. We observe the formation of a precipitate that disappeared when warming up the resin at 40°C under agitation. Due to this behavior, we speculate that the precipitate is probably unsaturated fatty acids that solidified or the photoinitiator that precipitated due to the low temperature. Because of the reversibility of the process, the resin doesn't require to be prepared strictly before each print but it can be stored in the fridge and warmed before its use. Table . Microalgae resin formulation: MEMO was mixed with different ratios of IBOMA, producing different resins. 2% (w/w) of BAPO was added to all the compositions.