Researchers at Lawrence Livermore National Laboratory (LLNL) have developed a new class of materials for their breakthrough volumetric 3D printing method, greatly expanding the range of material properties that can be achieved with this technology.
Volumetric 3D printing is different from the traditional layer-by-layer printing method. The material can generate the entire structure inside it at the same time, and the printing speed is faster. The new materials suitable for volumetric 3-D printing are called thiol ene resins, and they can be used with LLNL’s volumetric additive manufacturing (VAM) technology, including computational axial lithography (CAL), which has passed The 3-D patterned beam is projected into the vial of resin to produce the object. When the light cures the liquid resin into a solid, the vial will rotate at the desired point in the volume and the uncured resin will be discharged, leaving a three-dimensional object in a few seconds.
Previously, researchers used acrylic resins, and the objects produced by the CAL process were brittle and fragile. However, the new resin chemical composition created by carefully designing three different types of molecules is more versatile, providing researchers with flexible design space and wider mechanical properties. Using thiol-ene resins, the researchers used customized VAM printers at LLNL to create objects that are tough, strong, stretchable and flexible. This work was recently published in "Advanced Materials" magazine, and a key report in "Nature" magazine.
"These results are a key step towards our vision of using the VAM paradigm to significantly expand the types of materials that can be used for light-driven 3-D printing," said LLNL engineer Maxim Shusteff, who is the main researcher of this work. He is also the person in charge of the laboratory guidance research and development project for the development of advanced photopolymer materials.
In the paper, the researchers also demonstrated the first three-dimensional structure successfully printed in a thiol-ene resin through tomographic volume additive manufacturing. The researchers stated that the demonstration example creates a common reference for controlled 3-D manufacturing and comparison of resin systems.
The team concluded that this work represents a "significant advancement" in volumetric additive manufacturing, as they are working hard to achieve the goal of producing high-performance printing engineering polymers, especially the use of thiol-ene materials in bio-stents. The researchers said that thiol-ene materials have shown application prospects, including adhesives, electronics and as biological materials.
"By implementing the non-linear threshold response into a wide range of chemical reactions, we plan to print with resins, such as silicone or other materials that impart functions," said Caitlyn Cook, a materials engineer at LLNL.
The researchers added that by studying the performance of the resin under different light doses, their goal is to improve the consistency between the computational model and the experiment, and to apply the photochemical behavior to the computed tomography reconstruction to produce a three-dimensional image for constructing objects. model.
The title of the paper is "Highly Tunable ThiolEne Photoresins for Volumetric Additive Manufacturing".