Scientists at the Department of Energy’s Oak Ridge National Laboratory have created a recipe for a renewable 3D printing feedstock that could spur a profitable new use for an intractable biorefinery byproduct: lignin.
The discovery, detailed in Science Advances, expands ORNL’s achievements in lowering the cost of bioproducts by creating novel uses for lignin—the material left over from the processing of biomass. Lignin gives plants rigidity and also makes biomass resistant to being broken down into useful products.
“Finding new uses for lignin can improve the economics of the entire biorefining process,” said ORNL project lead Amit Naskar.
Researchers combined a melt-stable hardwood lignin with conventional plastic, a low-melting nylon, and carbon fiber to create a composite with just the right characteristics for extrusion and weld strength between layers during the printing process, as well as excellent mechanical properties.
The work is tricky. Lignin chars easily; unlike workhorse composites like acrylonitrile-butadiene-styrene (ABS) that are made of petroleum-based thermoplastics, lignin can only be heated to a certain temperature for softening and extrusion from a 3D-printing nozzle. Prolonged exposure to heat dramatically increases its viscosity—it becomes too thick to be extruded easily.
But when researchers combined lignin with nylon, they found a surprising result: the composite’s room temperature stiffness increased while its melt viscosity decreased. The lignin-nylon material had tensile strength similar to nylon alone and lower viscosity, in fact, than conventional ABS or high impact polystyrene.
The scientists conducted neutron scattering at the High Flux Isotope Reactor and used advanced microscopy at the Center for Nanophase Materials Science—both DOE Office of Science User Facilities at ORNL—to explore the composite’s molecular structure. They found that the combination of lignin and nylon “appeared to have almost a lubrication or plasticizing effect on the composite,” noted Naskar.
“Structural characteristics of lignin are critical to enhance 3D printability of the materials,” said ORNL’s Ngoc Nguyen who collaborated on the project.
Scientists were also able to mix in a higher percentage of lignin—40 to 50 percent by weight—a new achievement in the quest for a lignin-based printing material. ORNL scientists then added 4 to 16 percent carbon fiber into the mix. The new composite heats up more easily, flows faster for speedier printing, and results in a stronger product.
“ORNL’s world-class capabilities in materials characterization and synthesis are essential to the challenge of transforming byproducts like lignin into coproducts, generating potential new revenue streams for industry and creating novel renewable composites for advanced manufacturing,” said Moe Khaleel, associate laboratory director for Energy and Environmental Sciences.
The lignin-nylon composite is patent-pending and work is ongoing to refine the material and find other ways to process it.
The Latest on: 3D printing feedstock
via Google News
The Latest on: 3D printing feedstock
- 3D printer on International Space Station allows astronauts to recycle, reuse, repeat on February 15, 2019 at 2:19 pm
Among the cargo was the Refabricator, a machine that will accept plastic materials of various sizes and shapes and turn them into the feedstock used to 3D print items, according to a NASA press releas... […]
- NatureWorks Announces 100 Percent Third-Party Certified Sustainable Feedstock by 2020 on February 15, 2019 at 7:36 am
“We are very happy about NatureWorks’ commitment to sourcing sustainable agricultural feedstock,” said Gernot Klepper ... from coffee capsules and appliances to tea bags and 3D printing filament. Natu... […]
- 3D Printing Research CrAMmed: WFIRM, Argonne National Laboratory, Siemens on February 14, 2019 at 10:34 am
researchers are in hot pursuit of a metal 3D printer than can produce parts in low gravity conditions. Using a wire-based metal feedstock, the team has developed an 8-laser system, and plans to ... […]
- Xerox buys into metal 3D printing on February 12, 2019 at 5:52 pm
US printing giant Xerox has moved into metal 3D printing with the acquisition of New York-based ... low costs and with minimal waste by using wire feedstock to print up to 1,000 metal droplets per sec... […]
- Tethers Unlimited Recycler and 3D Printer Refabricator Operational on Board the ISS on February 10, 2019 at 11:53 pm
The Refabricator is meant to show, “Integrated recycling/3D printing capability thus provides significant cost savings by reducing the launch mass and volume required for printer feedstock while ... […]
- Polymers Market for 3D Printing Applications Dynamics, Forecast, Analysis and Supply Demand 2017 – 2025 on February 9, 2019 at 2:21 am
The 3D printing revolution focused on the usage of plastics due to its low-cost printer feedstock and high throughput. To date, 3D printing with metal has been expensive due to the high cost of titani... […]
- UL publishes ANSI/CAN/UL 2904 standard for assessing 3D printing chemical emissions on February 6, 2019 at 4:16 am
Throughout their research, the team deduced that 3D printer nozzle temperature ... operations handling both polymer and metal powdered feedstock for additive manufacturing. […]
- Filamentive announces 100% recycled 3D printer filament made from PET plastic bottles on February 6, 2019 at 2:34 am
The two companies work together with local collectors, recyclers and manufacturers to transform plastic waste into 3D printer filament. “In a world where less than 10% of plastic is recycled and in an ... […]
- Stratasys and 3D Systems Stocks Upgraded: Is a 3D Printing Rebound Coming? on January 29, 2019 at 9:30 am
... will exceed expectations for both sales of 3D printers and sales of "high margin" 3D printing feedstock. On the latter, Piper further notes that Stratasys has begun selling "elastomer ... […]
- ORNL researchers create renewable 3D printing feedstock from lignin on January 1, 2019 at 12:50 pm
In Tennessee, scientists at the Department of Energy’s Oak Ridge National Laboratory have created a recipe for a renewable 3D printing feedstock that could spur a profitable new use for an intractable ... […]
via Bing News