LOGAN — Cars that weigh less use less fuel. The question is how to make lighter vehicles without compromising safety or durability, and the answer may be spider silk.
“The fact that this material is stronger than steel, and more elastic than nylon, means it has possible applications in a wide variety of areas — this is just one my lab is exploring,” said Randy Lewis, a researcher at Utah State University.
Lewis is part of a team that received $1.9 million in funding from the U.S. Department of Energy to help reduce the use of petroleum. Other members of the team are from the University of California, Riverside, and Tennessee’s Oak Ridge National Laboratory.
“This program has two goals,” said Lewis, listing them as reducing dependence on petroleum in the production of vehicles, and reducing dependence on petroleum for fuel.
Many vehicle panels are manufactured using carbon fiber composites, instead of sheet metal.
“Currently, carbon fiber is produced almost exclusively from petroleum products,” said Lewis, which mostly come from other parts of the world. “One doesn’t want to have a major product completely dependent on imports.”
The advantage of using carbon fiber composites in automotive production is that they’re lightweight and strong.
“But a lot of those plastic and fiberglass things have very little flexibility to them, and they crack,” he said.
Lewis, and his team, are looking at the possibility of using spider silk products in the manufacturing process to create composites with even less weight, and with more flexibility.
“Our hope is that maybe small kinds of fender benders will not end up with complete deformation of those panels,” he said. “We could actually have a material that would give, and then come back again.”
USU has been experimenting with spider silk for 23 years. Lewis and his team have been able to produce synthetic silk using transgenic bacteria grown in their lab, and spin the spider silk proteins into fibers.
The researchers are exploring whether it makes sense to use spider silk fibers in the composites just as they are, or if it’s better to heat them to convert the silk to carbon fibers. They’re also looking at the form of the fibers, and whether there’s more strength and flexibility in simply laying the fibers down as a mat or weaving them.
USU researchers mainly use the golden orb weaver in their spider silk work, calling the arachnid sort of a “lab rat spider” that can produce six types of silk.
For this project they’re teaming up with Cheryl Hayashi, a professor at UC Riverside who used to be a student at USU.
“Her expertise is in looking at genomic differences between spider silks,” Lewis said. “If we feel she’s found something that might be better for this particular application — maybe it takes heat better, or something like that — we’ll use her gene sequences, and her proteins.”
The grant is for two years.
“The expectation is that by the end of year one we’re looking at fibers to be converted to carbon fibers, and at the same time we’re looking at how these things work in composite materials,” Lewis said.
