4/8/2026
Professors Nancy Sottos and Ioannis Chasiotis are engineering polymers that can protect themselves from the harsh conditions of low-earth orbit, with several formulations already showing dramatic reductions in material erosion during International Space Station trials. Their work could fundamentally change how satellites and spacecraft are built, and may one day enable the direct manufacturing of structural components in space.
Some of the smallest tools imaginable have the potential to revolutionize outer space manufacturing. Mounted on the outside of the International Space Station (ISS), cases measured at 1 inch by 1 inch — about the size of a jewelry box — contain samples of polymers exposed to a relentless onslaught of atomic oxygen and vacuum ultraviolet (VUV) radiation as the ISS makes low-orbit passes around Earth.
“At high velocity, when (atomic oxygen) impacts the surface of a polymer, it leads to undesirable chemical reactions, which leads to erosion of the surface. So it’s like the atmosphere is eating away the material,” said Nancy Sottos, head of the Department of Materials Science and Engineering at The Grainger College of Engineering, University of Illinois Urbana-Champaign.
Sottos is collaborating with Department of Aerospace Professor Ioannis Chasiotis on research seeking solutions to this material erosion. The duo sees weaknesses in polymer and metallic materials compared to the strong resiliency of glass and ceramic options in low-earth orbit (LEO), and by intentionally exposing polymer material samples in these missions, the results could fundamentally change how satellites and spacecrafts are built in the future.
The team has designed polymers capable of self-protection by reacting to atomic oxygen and forming a protective glassy surface layer. Different polymer formulations were first evaluated on the ground using an oxygen plasma asher available at the Beckman Institute for Advanced Science and Technology on the Illinois campus. While the asher provides a rapid method to evaluate the different polymer formulations on Earth, actual space exposure is essential to fully understand the self-protecting performance in LEO.
In October 2024, select material samples were shipped by the Illinois team to an implementation partner in Houston, who integrated them with other experiments from researchers across the United States to three large carriers. They were ultimately delivered to a National Aeronautics and Space Administration (NASA) facility for a compliance check and preparation for launching to the ISS in a SpaceX rocket.
Astronauts strategically mounted the three carriers -- each containing material samples from Illinois Grainger Engineering -- to three locations on the ISS to vary the levels of atomic oxygen exposure. Samples typically stay in orbit for about six months per mission.
“Our samples orbited the Earth for 201 days, completed 3,216 orbits and traveled 82 million miles before they were returned to us,” said Chasiotis.
A new series of sample modules from Illinois Grainger Engineering — the fifth materials testing mission this team has participated in to date — were placed on the ISS in January 2026. As of March 2026, these modules continue to face exposure to atomic oxygen and VUV radiation and will be returned to Earth in September 2026. While Sottos and Chasiotis wait for this next step, they started to analyze their results from the 2024 mission.
It’s a process that requires extensive care — if samples are damaged in any way by researchers, there is no going back to recreate them. The samples are prepared by Materials Science and Engineering graduate student Kenneth Cox, who is part of the Sottos research group.
“We characterize the samples that have returned from space by using Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy and other types of images,” Sottos explained.
Several of the polymer formulations showed significant reductions in erosion by atomic oxygen due to the formation of the anticipated glassy layer, and in some cases complete protection against further erosion. The team is in the process of drafting this work for publication and using the data obtained from space exposure to improve polymer formulations to be tested in the next space mission.
“We have some really, exciting, promising results,” added Chasiotis.
The polymers Sottos and Chasiotis are testing on the International Space Station aren't just being studied in isolation. They have a direct connection to one of the most ambitious manufacturing projects currently headed to space.
Mission Illinois, an effort funded by the Defense Advanced Research Projects Agency (DARPA), is led by Professor Sameh Tawfick of the Department of Mechanical Science and Engineering. Researchers are set to launch a composite tube manufacturing machine to the ISS in 2026 as part of DARPA's Novel Orbital and Moon Manufacturing, Materials and Mass-Efficient Design (NOM4D) program. The goal is to manufacture carbon fiber composite structural components directly on-orbit, eliminating the need to launch fully assembled structures from Earth.
The polymer at the heart of that manufacturing process — polydicyclopentadiene, or pDCPD — serves as the matrix material in the composites Mission Illinois is designed to produce in orbit. It is the same material Sottos and Chasiotis have among their samples currently orbiting Earth.
“They are studying the effects of different additives to improve the erosion resistance of this pDCPD polymer matrix on the space station now,” said Sottos. “We hope someday the materials strategies we are developing to prevent atomic oxygen erosion will be utilized in composites manufacturing in space.”
"It would be the next generation of materials for composites manufacturing," Chasiotis said. "We'll probably incorporate some of the materials that we're placing now at the ISS for characterization and evaluation."
In March 2025, Grainger Engineering formally launched the Center for In-Space Manufacturing of Resilient Structures (SpaceMaRS), organized by Chasiotis, to bring both threads together under one roof. The center unites eight faculty members across four departments, including Sottos, with expertise spanning composites processing, hypervelocity impact mechanics, space environment simulation and new material chemistries.
"The SpaceMaRS center integrates and focuses our strong technical efforts in in-space manufacturing and structural resiliency to AO erosion and Micrometeoroids and Orbital Debris (MMOD) impact to build the future in space that many of us have imagined," Chasiotis said.
A workshop, organized by SpaceMaRS and sponsored by Illinois Grainger Engineering, will take place at the Beckman Institute for Advanced Science and Technology on May 19-20, 2026. It will bring together researchers, program managers and technology developers from academia, government labs and industry to lay out a roadmap for in-space manufacturing of resilient space structures.
Illinois Grainger Engineering Affiliations
Ioannis Chasiotis is an Illinois Grainger Engineering professor of aerospace engineering in the Department of Aerospace Engineering. He is affiliated with the Holonyak Micro and Nanotechnology Laboratory and the Beckman Institute for Advanced Science and Technology. He holds a Caterpillar Professor of Engineering appointment.
Nancy R. Sottos is an Illinois Grainger Engineering professor of materials science and engineering in the Department of Materials Science and Engineering. She is affiliated with the Beckman Institute for Advanced Science and Technology. rShe is the department head for the Department of Materials Science and Engineering. She holds a Swanlund Endowed Chair appointment.