Vegetable Oils as Sustainable Inks for Additive Manufacturing: A Comparative Study

Abstract

The use of biobased materials in additive manufacturing is arising as a promising approach to modernize the polymer industry reducing its environmental impact. Herein, novel sustainable formulations are developed for digital light processing (DLP) using five vegetable oilssunflower, canola, soybean, olive, and sesame oilas feedstock. These vegetable oils are successfully modified incorporating photopolymerizable groups, i.e., acrylates, enabling printability. The oil-based formulations consisting of a functionalized oil and a photoinitiator are employed as inks for DLP without the need for further additives. The rheology and curing behavior of all the inks and printed materials are carefully investigated. The values obtained for their critical curing energy (E c) range from 14.52 to 18.49 mJ cm–2, allowing for fast printing. Interestingly, it is found that E c not only correlates with the average number of acrylate groups per molecule but also the viscosity plays a key role. Additionally, the thermal and mechanical properties are studied and compared. In summary, sunflower and canola oil derivatives offer a better cost-performance ratio than the state-of-the-art soybean oil inks and can be employed for 3D printing of complex geometries with high speed and resolution. This work demonstrates the potential of using biobased and inexpensive materials as high performance inks for DLP 3D printing and opens new possibilities for the next generation of sustainable 3D printing.

State-of-the-art UV-assisted 3D printing via a rapid syringe-extrusion approach for photoactive vegetable oil acrylates produced in one-step synthesis

“…29 A 3D printed canola oil acrylate, which contained the highest number of acrylate groups per molecule of the oils studied, showed the highest tensile modulus, followed by the state-of-the-art soybean oil-based resin. 30 Moreover, an excellent shape memory effect is achieved with 3D printed AESO-based resin, 31 while 3D printed UV curable bio-based vitrimer materials possess self-healing properties. 32 Recently, novel heat-resistant 3D printed acrylates from glycidyl methacrylate, succinic acid, and itaconic acid were obtained, showing superior properties to commercial high-temperature-resistant resins (Carbon CE221, Formlabs High Temp).…”

Vat Photopolymerization of Nanocellulose-Reinforced Vegetable Oil-Based Resins: Synergy in Morphology and Functionalization

“…Vasquez-Martels et al reported some limited applications of VO (sunflower, canola, soybean, olive, and sesame functionalized with acrylates) for SLA/DLP. 7 aforementioned work, compositions based on canola oil had the highest modulus (14 MPa) followed by sunflower and soybean oil (SO) (10 MPa). SO (the second most-produced VO in the world 8 ) has been successfully commercialized in the form of acrylated epoxidized soybean oil (AESO), which is typically found in various 3D printable resin compositions.…”

“…Therefore, VO-based resins have been investigated for UV-assisted 3D printing technologies. Vasquez-Martels et al reported some limited applications of VO (sunflower, canola, soybean, olive, and sesame functionalized with acrylates) for SLA/DLP . So far, VO-based resins have shown printing accuracy comparable to those of expensive, high-resolution commercial resins.…”

Loop 3D printing: recyclable photoresins for light-mediated additive manufacturing

“…The resolution of the printed objects was determined by printing custom designed specimens bearing engraved lines with widths varying between 1000 μm, 500 μm, 250 μm, and 100 μm. 45 Then the samples were examined by optical microscope (Zeiss AXIO Scope A1). All the features were clearly perceptible and retained the same shape, with ≈ 10 % isotropic shrinkage after the development process related to solvent evaporation (Figure S5).…”