The US Army Research Laboratory has found a way to convert post-consumer plastics into 3D printing materials. This allows trained veterans to quickly create replacement parts for military vehicles, weapons and equipment.
Using a process called solid-state shear pulverisation, researchers at the US Army Research Laboratory (ARL) were able to create composite thermoplastic filaments. In this process, shredded waste – mostly plastic bottles as well as some paper and cardboard – was pulverised in a twin-screw extruder to create a fine powder. This powder is then melt-processed into 3D printer filament.
The new composites have ‘improved mechanical properties’ such as improved strength for 3D printed materials. With an average strength of 70 Megapascal, it makes them helpful building blocks to repair military trucks, weapons and other important tools.
No waiting times
Luckily, most military bases in America have a 3D printer up and running. The downside is that military bases sometimes have to wait up to a month for a new filament to be restocked, says US Marine Corps Captain Anthony Molnar. ‘This process will change that,’ he notes.
‘Ideally, soldiers wouldn’t have to wait for the next supply truck to receive vital equipment,’ agrees ARL researcher Dr. Nicole Zander. ‘Now they can basically go into the cafeteria, gather discarded water bottles, milk jugs, cardboard boxes and other recyclable items, then use those materials as feedstocks for 3D printers to make tools, parts and other gadgets,’ she explains.
‘As our enemies have shown us, they can often outpace our ability to react to their new tactics and equipment. This new technology will enable the warfighter to more rapidly develop tools necessary to defeat an ever-changing enemy technology,’ remarks Captain Molnar.
‘Scratching the surface’
The US Marine Corps and research specialists are now collaborating to build a mobile recycling trailer for specially trained soldiers to fabricate 3D printing filaments from plastic waste. ‘We still have a lot to learn about how to best process these materials and what kinds of additives will improve their properties,’ Dr. Zander points out. ‘We’re just scratching the surface of what we can ultimately do with these discarded plastics.’
She presented her research findings at the recent meeting of the American Chemistry Society in Boston last month.