Researchers from UNSW, Australia, presented a new method for repairing 3D printed plastic parts. The procedure does not require the use of special temperatures or complex instruments, only the direct application of ultraviolet light.
The solution was obtained by adding a special component to the liquid resin used to print plastic parts. With the resulting material, quick and easy repairs can be made.
UV light to rejoin broken pieces of plastic
This can be done in a very simple way, with the direct application of a standard LED light on the printed plastic over the course of approximately one hour, causing a chemical reaction and consequently, the fusion of the two broken pieces.
The whole process actually makes the repaired plastic even stronger than it was before it was damaged. Further development and commercialization of the technique is expected to help reduce chemical waste in the future. With no need for plastic parts to be thrown away or even recycled, they could simply be repaired even when they remain embedded in a component that includes many other materials.
“In many places where a polymeric material is used, this technology can be used. So if a component fails, you can repair the material without throwing it away »said Dr. Nathaniel Corrigan. “There is an obvious environmental benefit because you don’t have to resynthesize a new material every time it breaks. We are increasing the useful life of these materials, which will reduce plastic waste “, also noted, in conversation with his house of studies.
The powdered additive that the UNSW team uses is a trithiocarbonate, known as a reversible addition fragmentation chain transfer agent (RAFT). The RAFT agent allows the reorganization of the nanoscopic network of elements that make up the material and allows the broken pieces to be merged.
This process takes approximately 30 minutes, during which time the UV LED lights should shine directly on the broken plastic, resulting in a complete repair, completed after approximately one hour of standing.
Experiments performed with this method, including the demonstration of a 3D printed violin (in the top image of this note), show that the strength of the self-healing plastic is fully recovered compared to its original uninterrupted state.
The research team commented that commercialization of the process is possible given the simplification and speed of their system compared to existing ways of repairing broken 3D printed materials.
“There are other processes that do this, but they rely on thermal chemistry to repair the material, and it usually takes around 24 hours and multiple heating cycles to achieve the same kind of result.”said Dr. Corrigan.
“Another restriction to that is that you need a furnace that is heated to a high temperature and obviously you cannot repair the plastic material on site, you would first have to disassemble it from the component, which adds a level of complexity and delay.”he noted as well. “With our system, you can leave the broken plastic in place and shine the light on the entire component. Only the additives on the surface of the material are affected, so it is easier and also speeds up the whole process ».
This new technology could potentially be used where advanced 3D-printed materials are currently used in specialized high-tech components, including wearable electronics, sensors, and even some shoemaking.