Extremely energy intensive materials are essential for a range of applications. The military and police need ballistic armor to ensure the safety of their personnel. The aerospace industry, on the other hand, needs materials that enable the capture, preservation and study of hypervelocity projectiles. However, current industry standards have at least one inherent limitation.
To solve these limitations, scientists at the University of Kent have created and planted a groundbreaking new shock-absorbing material that can stop supersonic impacts.
The TSAM (Talin Shock Absorbing Materials) family of innovative protein-based materials is the first known instance of a SynBio material (or synthetic biology) capable of deflecting supersonic projectile impacts. This makes it possible to create advanced materials for projectile capture and body armor to analyze the effects at extremely high speeds in space and the upper atmosphere (astrophysics).
Scientists used proteins that evolved over millennia to allow adequate energy dissipation. They incorporated a recombinant form of the mechanosensitive protein talin into a monomeric unit. They cross-linked it, resulting in the production of the first reported example of a talin shock absorbing material (TSAM).
Professor Ben Goult explained: “Our work on the protein talin, the cell’s natural shock absorber, has shown that this molecule contains a series of binary switching domains that open under tension and fold again when the tension is released. This response to force gives talin its molecular shock-absorbing properties, allowing our cells are protected from the effects of large force changes. When we polymerized talin into a TSAM, we found that the shock-absorbing properties of talin monomers gave the material incredible properties.”
The team then used this hydrogel material to demonstrate the practical use of TSAMs by subjecting it to supersonic impacts of 1.5 km/s, which is faster than the muzzle velocities of firearms, which are typically between 0.4 and 1.0 km/s. s, and the speed at which space debris impacts both natural and man-made objects. The scientists also found that TSAMs can retain these projectiles after impact, in addition to deflecting the impact of basalt particles (60 M in diameter) and larger pieces of aluminum shrapnel.
Most body armor in use today is a bulky ceramic face with a fiber-reinforced composite back. Additionally, while this armor is good at stopping bullets and flying debris, it is ineffective at stopping kinetic energy, which can cause physical trauma to the body beneath the armor.
In addition, due to its reduced structural integrity, this armor often takes permanent damage on a hit unless used continuously. This makes the use of TSAMs in new armor designs a viable replacement for existing conventional technologies, providing lighter, more durable armor that protects the wearer from a broader spectrum of injuries, including those caused by impact.
In the aerospace industry, where energy-dispersing materials are needed to efficiently collect space debris, space dust and micrometeoroids for further scientific research, TSAMs are also useful because they can capture and store projectiles after impact.
These intercepted projectiles also help build expensive spacecraft equipment, increasing the durability and safety of astronauts. Here, TSAMs can provide an alternative to aerogels, which are commonly used in industry but are prone to melting due to temperature increases caused by projectile impact.
Professor Jen Hiscock said: “This project grew out of an interdisciplinary collaboration between fundamental biology, chemistry and materials science, resulting in the production of this amazing new class of materials. We are very excited about the potential translational capabilities of TSAMs to solve real-world problems. We are actively researching this with the support of new employees within the defense and aerospace sector.”
- Jack A. Doolan, Luke S. Alesbrook et al. Next-generation protein-based materials trap projectiles and protect them from supersonic impacts. bioRxiv. DOI: 10.1101/2022.11.29.518433