Page 54 - Plastics News April 2018

teChnoLogy

Thermo Fisher helping US Army turn plastic waste into 3D parts

small footprint twin-screw extruder from Thermo to have similar strength. Researchers also tested and
A Fisher Scientific Inc. is helping the U.S. Army to reduce compared 3D printed radio brackets made from the
its plastic waste and, ultimately, shorten the lead time and recycled PET with brackets made from commercial
lower the cost for replacement parts needed by troops in ABS, and found that the recycled PET brackets failed at
remote areas. Waltham, Mass.-based Thermo Fisher sold a similar load. The study of the potential applications
its Process 11 parallel twin-screw extruder to the Army is being led by ARL researcher Nicole Zander and Capt.
in 2017 for an undisclosed amount. The machine will be Anthony Molnar of the U.S. Marine Corps. So far, research
used to produce 3D filament from post-consumer PET, has resulted in the production of a 3D filament made
which will then be used to 3D print spare parts as needed. of 100 percent recycled PET from bottles or containers
The 11 mm co-rotating twin-screw extruder is a fully without any chemical modifications or additives. "The
scalable unit with a maximum output of 2-5 pounds per idea is if they have a gear or a sprocket or something
hour. It has a 40:1 L/D ratio. As Thermo Fisher's smallest that's broken, it's very difficult for them to go out and
twin-screw extruder — the company offers diameters up source that. It's also dangerous for them to source it,
to 24 mm — it takes up just under 5 square feet of lab so they won't be able to be self-sufficient," Steve Post,
space. "It has the full functionality of most larger size business development manager at Thermo Fisher, said
compounding extruders," he said.While the Army is not "Our role was to come up with a machine that was
new to additive manufacturing — ARL has been 3D printing scalable [and] could process these materials," he added.
parts for about 18 years — its research in determining "With polyester, you're driving off the moisture, so that's
recycled PET as a viable feedstock is a big step toward why you need something that's fully scalable." PET water
improving sustainability by reducing plastics waste. The bottles and packaging are among the most common types
strategy stems from a collaboration between the U.S. Army of waste found on the battlefield, the Army said.
Research Laboratory (ARL) and the U.S. Marine Corps that
Scientists engineer plastics-
resulted in the discovery of using recyclable plastics from
eating enzyme

Researchers in the United States and England have
engineered an enzyme that could help solve the
problem of PET bottle litter. The breakthrough is the
latest in a series of tantalizing research results hinting
that certain enzymes and microbes that use them might
pave a way to degrade mountains of plastics scrap.
Scientists at the U.S. Department of Energy's National
Renewable Energy Laboratory and the University of
Portsmouth say they have tweaked a bacterium's
enzyme to improve its ability to degrade PET. The
natural enzyme is in a bacterium called Ideonella
discarded water bottles, milk jugs and yogurt containers, sakaiensis, which researchers recently found was
for example, for 3D printing parts that soldiers may need degrading PET in a Japanese waste recycling center.
on the battlefield or in more isolated areas. McGeehan and colleagues were examining the structure
of the natural, PET-degrading enzyme when they
Mechanical testing, such as uniaxial tensile and three- found they could increase the degradation rate by
point bending experiments, with the recycled PET was manipulating the chemical structure of the enzyme.
done in the laboratory. Zander said the recycled PET The improvement was modest, scientists believe bigger
was compared with commercial filaments and was found improvements are possible

Plastics News April 2018 54 23 43 April 2015 Plastics News
March 2017 | Plastics News
•
•