Ellen Phiddian
Cosmos science journalist
Researchers have developed a way to 3D-print a plastic which is cheap, recyclable, stretchable, and flexible.
The plastic is made from a substance called a thermoplastic elastomer. The commercially available elastomer is made from several different long polymer molecules.
This material can be heated into a liquid and reformed. As a solid, the different polymers separate and form into neat cylindrical “nanostructures”, about 5 nanometres thick (or twice the width of a DNA molecule).
“The elastomer we are using forms nanostructures that we are able to control,” says Assistant Professor Emily Davidson, from Princeton University, USA, co-author of a paper published in Advanced Functional Materials.
“We can create materials that have tailored properties in different directions.”
The team used its previous research on these materials to develop a 3D-printing technique that would take advantage of the way they flowed, to form the right nanostructures.
“I think one of the coolest parts of this technique is the many roles that thermal annealing plays,” says lead author Alice Ferguson, a graduate student at Princeton.
“It both drastically improves the properties after printing, and allows the things we print to be reusable many times and even self-heal if the item gets damaged or broken.”
The team tested this by cutting apart one of the flexible plastics, and then annealing it back together.
The repaired plastic had exactly the same properties as the original.
The researchers say their technique is “highly scalable”.
They’re now testing to see how the plastic performs for applications like wearable electronics and biomedical devices.
