TECHNOLOGY FOCUS
Materials
A roundup of recent advances in engineering technology. In this issue, a look at innovative materials developed for multiple applications.
FREQUENCY-TUNED NOISE BARRIERS
Researchers are rethinking how sound-absorbing materials are engineered by turning to mineral foams. Empa has developed panels made from a lightweight, porous mineral matrix that is only a fraction of the size yet still highly effective, unlike conventional absorbers that require bulk and thickness to reduce noise. This approach not only reduces material use but also makes the absorbers easier to integrate into tight spaces.
The material’s porous structure is key: it allows air vibrations to dissipate within the foam, cutting down unwanted sound. By adjusting pore size and the composition of the mineral mixture, the absorbers can be tuned to target specific noise frequencies—whether that’s traffic rumble, machinery hum, or other environmental sound sources. This tunability distinguishes them from traditional one-size-fits-all solutions.
Due to their reduced thickness and adaptable acoustic properties, these mineral-based absorbers can be deployed in various contexts, including building façades and infrastructure projects where space and weight are at a premium.
SILICONE RUBBER ENHANCES EV BATTERY SAFETY
Amid growing demand for safer and more efficient battery systems in the electric mobility sector, WACKER has introduced a new silicone rubber called ELASTOSIL that is designed to improve the safety of high-voltage traction batteries in electric vehicles. The material is engineered to insulate busbars—critical components that connect battery cells—by providing reliable electrical insulation and thermal stability.
Silicone rubber offers several advantages over traditional materials. It resists high temperatures and mechanical stress, ensuring long-term durability in demanding automotive environments. Additionally, the material’s high elasticity and impact strength enables easy integration into complex battery designs. Another perk is that ELASTOSIL can be extruded, making the sheathing process cost-effective.
From a safety standpoint, it’s also flame-resistant and prevents leakage currents. Should a fire occur, the cured rubber forms a solid ceramic material that sheaths the busbar and continues to insulate it electrically, preventing short circuits.
HAUTE COUTURE MEETS PROTEIN FIBER
Spiber Inc., a Japanese biotechnology company, collaborated with designer Iris van Herpen to create a haute couture gown for Paris Fashion Week AW2025 using the company’s brewed protein fiber. This lab-grown protein material is produced via microbial fermentation from sustainable biomass feedstocks, offering a bio-based alternative to traditional textiles. The fiber combines lightweight structure with high tensile strength and biodegradability, making it suitable for both performance and design-driven applications.
The brewed protein fiber is designed to be versatile, allowing complex forms, textures, and patterns while maintaining mechanical stability. Its renewable feedstocks, often derived from agricultural byproducts, support a more circular approach to material sourcing. The fiber’s inherent properties also reduce reliance on synthetic polymers, aligning advanced textile engineering with environmental sustainability.
“Biomimicry is ever-present in Spiber’s approach, and that is truly similar to our own methods. Fusing the organic with the innovative, recreating nature’s way of making a material, starting with a protein… Spiber has been able to translate a complex technology to meet the needs of designers and create something truly wearable, which is a rare quality,” said Dutch haute couture designer Iris van Herpen in a press statement.
EDIBLE NANOFIBERS?
Researchers at Penn State have created a new class of edible, biodegradable fibers by combining milk protein (casein) with plant-derived cellulose. Using an electrospinning process, the team produces ultrafine fibers—thousands of times thinner than a human hair—that can be assembled into mats or films. These fibers provide a renewable alternative to synthetic materials, with potential applications in food packaging and biomedical fields.
To enhance mechanical properties and fiber uniformity, the researchers incorporated hydroxypropyl methylcellulose (HPMC) into the blend. Optimizing the cellulose-to-casein ratio enabled them to produce smooth, bead-free fibers that retain both flexibility and strength. When exposed to moisture, the mats can form clear, edible films suitable for wrapping or coating foods.
By leveraging renewable feedstocks and scalable fiber-processing techniques, the research opens new avenues for sustainable packaging, wound dressings, and other applications where biodegradability and safety are critical.
3D PRINTING STOOLS WITH ALGAE
At Expo 2025 in Osaka, Japan, Mitsubishi Chemical Corporation used its bio-based engineering plastic DURABIO to make 3D-printed stools. This plastic is made from plant-based isosorbide and combines transparency and durability, offering a high-performance alternative to conventional plastics. The material’s optical clarity and mechanical strength make it well-suited for both functional and design-driven applications.
The plastic is blended with algae-based components to produce lightweight, structurally stable stools while demonstrating the potential of renewable feedstocks in manufacturing. DURABIO’s resistance to weathering and its mechanical balance enable complex 3D-printed forms that maintain long-term performance, expanding the possibilities for sustainable product design.
The company’s goal in creating the stools was to showcases how bio-based engineering plastics can be used in practical, visually appealing applications. This project also showcased the material’s versatility, combining plant-derived polymers with advanced manufacturing to minimize environmental impact while maintaining quality and functionality.
CLEANER, RENEWABLE TIRES
Jaguar Land Rover is launching tires with more than 70 percent renewable and recycled content later in 2025 on new Range Rover models. Developed in collaboration with Pirelli, the design replaces conventional feedstocks with a blend of plant-based resins, silica derived from rice-husk ash, natural rubber, recycled carbon black from end-of-life tires, and recycled steel for reinforcement. The result is a high-performance tire that reduces reliance on fossil-based materials without altering driving dynamics.
The silica is sourced from rice-husk ash—a byproduct of agriculture—lowering the environmental impact compared to traditional mined silica. Meanwhile recycled carbon black and steel bring valuable materials back into the production cycle. Plant-based resins derived from renewable sources help bind the tire compounds while supporting grip, handling, and braking performance on both wet and dry surfaces.
All renewable and recycled materials in the tire will be certified by independent bodies to ensure traceability. This initiative builds on JLR’s 2024 rollout of FSC-certified natural rubber tires.
© 2025 The American Society of Mechanical Engineers. All rights reserved.