Replacing Kevlar: Synthetic Hagfish Fibers @introtomaterialsscience--g4

Uploaded May 2017 | Updated September 2026, 4 days ago

The focus of our video is the structure, properties, and processing of synthetic hagfish fibers and their use in bulletproof vests.

Hagfish slime is a biomaterial that is produced from the hagfish. Researchers are taking only the threads from the slime and replicating them.

Current bulletproof vests are made of kevlar. However, kevlar is hard to produce. Furthermore, kevlar fibers slip against one another when submerged in water, allowing sharp objects to pass through. Synthetic hagfish threads could replace kevlar due to their mechanical properties.

Hagfish fibers are 1 to 3 micrometers in diameter. They are very elastic when in their original state and are in the shape of a spring (alpha helix).

Advantages of synthetic hagfish fibers over kevlar: 1) hagfish slime threads are much more easily produced, and 2) hagfish slime threads can be adjusted in strength and stiffness to suit the need of the bulletproof vest.

The hagfish fibers are initially very elastic, but become a similar strength as kevlar 29 when they are stretched. This is because the threads transition from an alpha helix to a beta sheet crystal structure after stretching.

Researchers can use E. coli bacteria to create synthetic hagfish fibers. This is much simpler than producing kevlar. Researchers verified that synthetic hagfish slime threads match the original hagfish fiber properties.

Alternatively, we can use BOTH kevlar and hagfish fibers together in a composite material. This would allow researchers to adjust the elasticity of hagfish fibers while keeping a base strength in kevlar.

The processing of synthetic hagfish fibers (production and stretching) lead to a change in its structure (alpha coils to beta-crystals), which in turn leads to the strong and stiff mechanical properties hagfish fibers. The ease of processing and the mechanical properties of hagfish fibers make it a viable material for both replacing and supplementing kevlar in bulletproof vests.

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Replacing Kevlar: Synthetic Hagfish Fibers

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