Empa Researchers Strengthen Satellite Insulation with Ultra Thin Interlayer Technology

Superinsulation: The sunshield of the James Webb Space Telescope is made of the same material that the Empa researchers are working with. Image: NASA/Goddard/Chris Gunn

(IN BRIEF) Empa researchers have strengthened ultra-light, flexible composite materials used in satellite insulation by introducing an artificial ultra-thin interlayer between metal and polymer films. The five-nanometre layer significantly improves elasticity and resistance to cracking under extreme thermal and mechanical stress, addressing key challenges faced by spacecraft exposed to repeated temperature swings. While the research builds on materials already used in missions such as the James Webb Space Telescope, its implications extend well beyond space applications. The approach could enable more durable multilayer systems for flexible electronics, smart textiles and medical sensors, supporting the development of foldable, rollable and highly resilient devices.

(PRESS RELEASE) DÜBENDORF, 16-Dec-2025 — /EuropaWire/ — Researchers at Empa have developed a new approach to strengthening ultra-light, flexible composite materials widely used in space applications by introducing an ultra-thin intermediate layer between metal and polymer films. The breakthrough improves the durability and flexibility of so-called multilayer insulation materials, which protect satellites and space probes from extreme temperature fluctuations, and could also open new possibilities for flexible electronics and medical sensor technologies on Earth.

In a vacuum: Empa doctoral student Johanna Byloff prepares the samples on the coating machine of the Empa spin-off Swiss Cluster. Image: Roland Richter, Empa

Multilayer insulation, often seen as the metallic foil wrapping satellites, consists of polymer films coated with thin metal layers, typically aluminum. These materials play a critical role in shielding sensitive onboard electronics from temperature differences of up to 200 degrees Celsius, which satellites in low Earth orbit experience repeatedly as they move between sunlight and Earth’s shadow. While the insulation must provide strong thermal protection, it also needs to withstand mechanical stress, vacuum conditions and repeated thermal cycling.

At Empa’s Laboratory for Mechanics of Materials and Nanostructures in Thun, researchers focused on improving the interface between the polymer substrate and the metal coating. Polyimide, a highly resistant polymer commonly used in space applications, already exhibits good adhesion with aluminum due to a naturally forming interlayer only a few nanometres thick. Empa researcher Barbara Putz and her team set out to better understand this interface and to reproduce it in a controlled way by deliberately introducing an artificial intermediate layer.

Using a model system consisting of a 50-micrometre polyimide film coated with aluminum, the researchers added an aluminum oxide interlayer just five nanometres thick. Producing such an ultra-thin layer required precise processing under vacuum conditions, made possible using coating equipment from Swiss Cluster AG, an Empa spin-off specialising in advanced coating technologies. This setup allowed multiple coating steps to be carried out sequentially without breaking the vacuum, ensuring clean and reproducible interfaces.

Tests showed that the engineered interlayer significantly enhanced the composite’s mechanical performance. The material became more elastic and showed much greater resistance to cracking and flaking when subjected to tensile stress and temperature shocks. This is particularly important for space structures such as large satellite sunshields, which must survive folding during launch, deployment in orbit and potential impacts from micrometeoroids without damage spreading across the surface.

Empa researcher Barbara Putz has received the Swiss National Science Foundation (SNSF) Ambizione Grant for her research project. Image: Empa

Beyond satellite insulation, the researchers see broad potential for the technology in terrestrial applications. By varying the thickness of the interlayer and applying it to other polymer substrates, the approach could enable multilayer systems that were previously impractical due to poor adhesion. This could benefit flexible electronics, including foldable devices, smart textiles and thin-film medical sensors, where improved mechanical resilience is essential for reliability and long-term use.

The research is supported by an Ambizione Grant from the Swiss National Science Foundation, reflecting its potential to advance both space technology and next-generation flexible materials.

Further information

Dr. Barbara Putz
Empa, Mechanics of Materials and Nanostructures
Phone +41 58 765 62 54
barbara.putz@empa.ch

Johanna Byloff
Empa, Mechanics of Materials and Nanostructures
Phone +41 58 765 63 12
johanna.byloff@empa.ch

Editor / Media Contact

Anna Ettlin
Communications
Phone +41 58 765 47 33
redaktion@empa.ch

Literature

J Byloff, V Devulapalli, D Casari, TEJ Edwards, COW Trost, MJ Cordill, SA Husain, PO Renault, D Faurie, B Putz: From Mechanics to Electronics: Influence of ALD Interlayers on the Multiaxial Electro‐Mechanical Behavior of Metal–Oxide Bilayers; Advanced Functional Materials (2025); doi: 10.1002/adfm.202526343

J Byloff, COW Trost, V Devulapalli, S Altaf Husain, D Faurie, PO Renault, TEJ Edwards, MJ Cordill, D Casari, B Putz: Atomic Layer-Deposited Interlayers for Robust Metal–Polymer Interfaces; ACS Applied Materials & Interfaces (2025); doi: 10.1021/acsami.5c05156

SOURCE: EMPA