Ellen Phiddian
Cosmos science journalist
Hard, durable thermoset plastics appear everywhere from aircraft coatings to hip replacements.
But they’re extremely difficult to recycle, and millions of tonnes end up in landfill, or incinerated into the atmosphere, each year.
Now a team of researchers has made a plastic which boasts the tough properties of a thermoset, but which can be recycled.
“The whole process, from creating to reusing, is more environmentally friendly than current materials,” says Reagan Dreiling, a doctoral student in chemistry at Cornell University, USA, and first author of a paper published in Nature.
The team used a compound called dihydrofuran as their building block. Composed of carbon, oxygen and hydrogen, dihydrofuran can be made from biomass extracts.
Dreiling used dihydrofuran to build long polymer molecules. The polymer was cross-linked: the long chains of molecules were bonded to each other, rendering the substance very strong.
But unlike commercial cross-linked thermosets, this polymer could be taken apart again by heating, and would degrade naturally in the environment.
The team was able to tune the material’s properties to make it as strong or stiff as commercial thermosets.
The researchers are now looking at applications for their new material, and testing to see whether it could be used for 3D printing.
“We’ve spent 100 years trying to make polymers that last forever, and we’ve realized that’s not actually a good thing,” says senior author Brett Fors, a professor of chemistry at Cornell.
“Now we’re making polymers that don’t last forever, that can environmentally degrade.”
