Researchers at the University of Chicago’s Pritzker School of Molecular Engineering have developed a “pluripotent plastic.” Like pluripotent stem cells which can give rise to any type of adult cell in the human body, their plastic can take on many final forms. It was described in the journal Science.
Temperature Adjustment can Change the Properties
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We believe, this is the first example of a synthetic material that exhibits pluripotent behavior,” said Stuart Rowan, the Barry L. MacLean professor for Molecular Engineering Innovation and Enterprise and senior author of the new work. “
We believe that it paves the way toward a different way of thinking material design.”
To develop the new material, Rowan worked with PME assistant professor Shrayesh Patel, graduate student Nicholas Boynton, and colleagues at Argonne National Laboratory, the U.S. Army Research Laboratory, NASA, and the National Institute for Standards and Technology (NIST).
The pluripotent material is made up of polymers containing “dynamic covalent bonds”. These bonds can break and re-form reversibly. Heating the material only to low temperatures (around 140°Fahrenheit, or 60°C) allows the formation of more bonds. This results in stiff, high-strength materials at room temperature. These could be used to make plastic utensils, among other things.
However, heating to higher temperatures (around 230°F/110°C) results in fewer bonds being formed. This in turn results in a more soft, extensible material that can be used for instance, as a pressure-sensitive adhesive.
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We were surprised by how many different mechanical properties we could get,” said Boynton. “
From this single feedstock material, we can turn it into something that behaves like a hard, high-strength material or something that’s quite flexible, like a rubber band.”
By adjusting the temperature between the two extremes, its possible to fine-tune the properties of the materials. It also gives them a variety of properties and functions.
The resulting material stable at room temperature. However, it could be tempered again at a different temperature to access a new and different state.
On-demand Reuse Materials in Resource-scare Environments
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If you’re going to live on the moon or Mars, you can’t take a bunch of materials with you, and you don’t have Amazon Prime shipping, so it’d be great if you have this one material that you can turn into a bunch of different stuff,” said Boynton.
It can be employed as on-demand reuse materials in resource-scare environments, such as on the moon or Mars. This material also opens the door to different approaches to plastic recycling (where there is no need to separate out the different plastics we use today).
The team is now investigating how to improve the range of mechanical properties that can be imbued in their pluripotent materials. The goal is creating materials to replace current plastics as well as materials with new functional properties.
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We want to reframe the way we think about designing materials,” said Rowan. “
Instead of designing one material for one application, let’s flip that on its head and see if we can make one material that can be differentiated to be useful for many applications.”
Source: University of Chicago