TAGS: Sustainability / Natural Coatings Smart Coatings
Researchers at Northeastern University’s Kostas Research Institute work with a synthesized version of xanthommatin, a naturally occurring dye present in the bodies of cephalopods like octopi and squid, to create colorants that change in response to different stimuli. Their latest discovery is using this to create paint that can change colors when exposed to light.
Cephalopods change colors rapidly in response to threats or even just change in light thanks to xanthommatin.
Unique Nature of Cephalopods’ Skin
KRI focuses its work on interesting components from natural materials, looking into ways those components can be replicated and used in the real world. Cephalopods have been a starting point due to the unique nature of their skin.
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Their color change is so rapid and it’s so vibrant and it’s so intense,” said Cassandra Martin, research scientist at the institute. “
There’s not a lot of natural systems out there that change that fast and there’s not a lot of color-changing materials that are that fast without requiring a lot of external (changes).”
The staff at KRI has long worked to replicate this. Previously, the lab used this to create wearable patches that change color when the wearer gets too much sun. The team wanted to try to find a way to make a material where this change could be reversed to return the material back to its original color.
Kaitlyn Flynn, PhD. student in chemistry at Northeastern University and the team found that titanium dioxide served as a conductor for the color change. Mixing different amounts with the xanthommatin could speed up the change or add to the intensity of the color shift.
The changes can happen in as quickly as five minutes and can last as long as 24 hours, depending on how long the paint is exposed to light. The colorant can easily be made in as little as two hours and added to water or oil-based paints.
Eco-friendly Alternative to Current Paints
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We’ve imagined a scenario where if you want to have art that changes from day to day on an interior wall, like maybe in a coffee shop or something you could use a regular projector to project a pattern onto the wall, temporarily paint in this color and this pattern or this art, and then over time that fades away and you can redo it again, ideally as many times as you want,” said Dan Wilson, senior research scientist at the Kostas Research Institute.
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We can create temporary artwork or art or paint that could potentially track the weather or track the environment that it’s in,” added Wilson.
Besides the ability to create temporary art, this discovery has environmental implications. It can serve as an eco-friendly alternative to paints currently on the market.
Harmful Chemicals in Paints
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Paints that are commercially used nowadays can have harmful chemicals in them, so they can have things that can be harmful to the people that are painting them,” said Flynn. “
The fumes can be super harmful. They can be harmful long term if you’re exposed to them for a long time.”
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They can also leach out into the environment. Searching for a more natural way to make these paints creates a safer environment for the people using it and for the people that are going to be exposed to it,” added Flynn.
Moving forward, Flynn and Martin said they hope they can apply this system to other materials and expand beyond the yellow-red color palette they used in the initial experiment. They also hope to get to the point where the user can decide how quickly they want the colors to change on the paint.
Source: Northeastern University