Kevlar has been the Army's go-to body armor for decades, but a new technology might be challenging that paradigm. Kraig Biocraft, a bioengineering company based in Michigan, has genetically altered silkworms to produce spider silk. Today, they announced an Army contract to develop this silk, called Dragon Silk, for use in body armor.
Spider silk is one of the strongest natural fibers, but it's difficult to produce in large amounts. Spiders are territorial and cannibalistic, so it's nearly impossible to create a cost-effective spider farm. To combat this problem, Kraig Biocraft inserted the genes for making spider silk into silkworms. The result was a composite silk that was as strong as normal spider silk yet much easier to produce.
Dragon Silk has a number of applications, particularly in surgery. Many sutures are done with biodegradable silkworm silk, but the increased strength of Dragon Silk allows for much thinner threads. This is useful when performing surgery in sensitive areas, such as the eyes and brain.
The Army's Soldier Protection and Individual Equipment (PM-SPIE) office is giving Kraig Biocraft a $100,000 grant to test their Dragon Silk as a form of body armor. The company will produce a series of ballistic "shoot packs" with different thread counts, thicknesses, and construction techniques to see how the Dragon Silk performs. If it meets expectations, the Army is prepared to increase the grant to $1 million.
Dragon Silk's primary advantage over traditional Kevlar is its flexibility. Kevlar is slightly more durable than Dragon Silk, with a strength of 3 gigapascals (GPa) compared to Dragon Silk's strength of 2 GPa. However, Kevlar only has an elasticity of 3 percent, meaning it's almost completely inflexible. Dragon Silk has an elasticity of 30 to 40 percent, which offsets the slightly reduced strength.
If Kraig Biocraft is successful, silkworm farms may soon be spinning up the gear that keeps frontline troops safe.
Source: Defense One
