A recent discovery at the famed Massachusetts Institute of Technology (MIT) found that the bellies of lobsters are comprised of hydrogels (a membrane that contains gels or polymers suspended in water) that exhibit amazing strength and flexibility. Strength and flexibility are properties that are at the top of desired values in body armor. This discovery could change the future of body armor for military and law enforcement applications. As someone who has worn body armor in a variety of formats, I can attest to the current state of affairs and the need for continued improvements. And, as someone who has eaten a lobster (I lived in Massachusetts while stationed at the now defunct Fort Devens) I can also attest to the difficulty in cutting the belly open. I usually resort to industrial kitchen scissors for such work. So, I can see where the possibilities may lead us. But for now, we must accept our current crop of fabrics and materials for body armor. And they do work quite well, all things considered.
Body armor development has actually been rather rapid in the recent past. We have gone in just a few short decades from cumbersome armor that was of questionable quality and bulky, to a vest that can be worn in all weather, underneath our shirts, with only minimal discomfort. That is due, in large part to better living through chemicals. Specifically, Kevlar.
Kevlar is a synthetic fiber manufactured by DuPont. It was not until the mid-1970s that DuPont was able to create a fiber that had the strength to stop bullets, while being flexible enough for everyday wear. Even then, the earliest vests were uncomfortable by todays standards and lacked the weight to strength ratio we enjoy now. However, these vests were far more advanced than prior vests manufactured in the late 1900s. Original Kevlar vests worked well enough for bullets, but interestingly enough, would not protect the user from stabbing attacks. DuPont did not stop at their original creation. They have since refined their product several times to increase both flexibility and strength. Kevlar has found its way into a variety of items besides just ballistic vests. For example, it is very common for modern motorcycle safety clothing to be made of fabrics which make use of Kevlar for abrasion and heat protection.
In addition to Kevlar, there are some other materials which are in use for ballistic protection. Earliest attempts at flexible ballistic protection included cotton (tightly packed and in multiple layers) as well as silk. Silk has an amazing strength to weight ratio, is fabulously flexible, and also does not hold wrinkles. However, silk is not impervious to heat and is rather expensive.
However, a polymer fiber, similar to silk is currently in use as an alternative to Kevlar for ballistic vests. That fiber is Ultra-high-molecular-weight polyethylene. Commonly abbreviated UHMWPE. UHMWPE is made using a centrifugal process to create strands of fiber that are then wrapped in outer strands. The resulting fibers are almost half again as strong as Kevlar. UHMWPE is becoming the go to fiber for our current crop of emerging ballistic vests.
Not all body armor is soft and flexible. Many users choose to include hard plates for chest and back protection from rifle rounds. These plates can be made from a variety of materials. For some time, I used plates made of a titanium alloy which were very light for the level of protection they afforded. Pressed, modern plastics can be formed into hard shapes and used for “rifle plates”.
Ceramic is also popular when wrapped in Kevlar of other similar material. Such plates are usually a one time use affair and must be replaced after being struck with a bullet. They can also be more delicate than other types of plates and users need to be cautious to not drop the ceramic plates. Thin metal plates, wrapped in Kevlar or UHMWPE are now widely available and make for excellent bullet stoppers. However, these plates are not very flexible, nor are they light weight. The trade off between protection and usability continues to play out.
While we might be a long way from lobster armor, the current, modern fibers are a significant improvement over the full steel plates once used for such duties.
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