In a recent 3-D printing breakthrough researchers successfully created mechanical sensors at a low cost.
A research team made a bone-shaped plastic tab that turns purple when stretched, allowing them to easily measure the force of an object, the University of Washington reported.
"At the UW, this is a marriage that's been waiting to happen - [3-D] printing from the engineering side, and functional materials from the chemistry side," said Andrew J. Boydston, a UW assistant professor of chemistry. He is a corresponding author on a recent paper in the American Chemical Society's journal of Applied Materials and Interfaces.
The scientists created a polymer made up of repeated units strung together, and put it through a 3-D printer. One printer head contained flexible polycaprolactone, and the other a type of plastic that is almost identical, minus the inclusion of the color-changing molecule spiropyran.
"We wanted to demonstrate that the functional chemistry could be incorporated readily into already printable materials," Boydston said. "We found that designer chemistry can be incorporated into 3-D printing very rapidly."
The final product is a small white plastic tab containing strips that turn purple under force. The entire device costs under a dollar to print and can be created in less than 15 minutes. This could lead to new innovations such as a football helmet that changes color when hit with sufficient force.
The 3-D printing technology could allow the material to be created in different configurations, causing the molecules to respond in different ways.
"Maybe the material isn't currently under stress, but it had been several times prior to your observing it. And so these types of materials could record that load history," Boydston said.
The novel material could even lead to individualized medical implants or other custom-shaped objects that respond to their environments.
"This is definitely an area that we want to continue to expand into," Boydston concluded.
The findings were published in a recent edition of the American Chemical Society's journal of Applied Materials and Interfaces.
