printing out molecules that can respond to their surroundings. A research
project at the University of Washington merges custom chemistry and 3-D
printing. Scientists created a bone-shaped plastic tab that turns purple under
stretching, offering an easy way to record the force on an object. “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 corresponding
author on a recent paper in the American Chemical Society’s journal of Applied
Materials and Interfaces.
top panel is a 3-D printed plastic tab with the letters “UW” printed in a
slightly different material. The bottom panel is the same material after
stretching. (Credit: A.J. Boydston / UW)
Peterson and Michael Larsen, UW doctoral students in chemistry, created a
polymer, or plastic made up of many repeated units strung together, and fed the
soft plastic into the UW chemistry lab’s commercial 3-D printer. One print head
contained polycaprolactone, similar to what a 3-D printer company sells as
Flexible Filament. The other print head contained a plastic that is 99.5
percent identical but the UW team made occasional insertions of a molecule,
spiropyran, that changes color when it is stretched.
researchers put slightly different plastics in each of the printer’s two print
heads. One of the plastics changes color when it is stretched. (Credit: A.J.
Boydston / UW)
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 printed tab is a piece of white plastic with barely visible
stripes that turn purple under force. It acts as an inexpensive, mechanical
sensor with no electronic parts. The whole device took about 15 minutes to
print from materials that cost less than a dollar.
sensor might be used to record force or strain on a building or other structure.
Boydston would like to develop a sensor that also records the speed of the
force, or impact, which could allow for a football helmet that changes color
when hit with sufficient force. The project is part of a recent collaboration
between Boydston’s group and co-authors Mark Ganter and Duane Storti, UW
mechanical engineers who have developed new 3-D printing materials and
techniques. (Source: Phys.org)