Body armor has been around since medieval times in various forms. Constantly undergoing improvements throughout the years, a newer form is on the horizon. Scientists are currently developing liquid " body armor the lightest form yet.
Body armor over the years
The earliest forms of body armor were made of metal plates and provided great protection against swords, but musket balls would go right through them. It wasn't until the English Civil Wars that two layers of metal plate were developed and proved to be musket-proof. The outer layer absorbed the shock and the thinner, inner layer slowed the bullet.
But, as weapons continued to develop over the years, so did the making of body armor. The overall dual layer design is essentially what is still used today. However, the materials have changed a great deal; additionally, the metal proved to limit mobility for soldiers who needed to move without restriction.
The British started using armor made of manganese plates, which made for the first form of armor that allowed for mobility and offered protection against low-velocity bullets. The first flak jacket, which protected against low-velocity shrapnel found to cause more injuries than bullets was made of nylon and developed in Europe during 1943.
It wasn't until the end of WWII that the bullet-proof vests made of fiberglass laminate (also called Doron Plate) were developed. Smith and Wesson marketed the barrier vest in 1969, which was made of quilted nylon and steel plates. This was the first bullet-proof vest to succeed outside of the military.
The discovery that revolutionized body armor
Stephanie Kwolek, a research chemist at DuPont, was experimenting with liquid crystalline polymers to create lightweight but strong tires. This is when she made a groundbreaking advancement which led to the development of Kevlar. This material can be made into ropes or fabric sheets and is used not only in bullet-proof vests but also in tires, racing sails, and shoes, to name a few.
Kevlar is used in combat helmets and in ballistic face masks and vests. The material features high heat resistance but is actually a bit stronger at cooler temperatures. Its use in body armor completely changed the game. Armor made with woven and layered fabric (usually 20-40 layers) made from Kevlar is five times stronger than steel. With the introduction of body armor in the police force, it was estimated that 2,000 lives were saved between the 1980s and 2006.
What is liquid body armor and how is it made?
The U.S. Army Research Laboratory has been working on a new development in body armor: liquid body armor. It's lightweight, flexible, and provides protection and mobility like no other body armor has been able to in the past.
Throughout history, designs in body armor that allowed for more movement lacked complete protection. This development in liquid body armor relies on something called shear thickening fluid. " Made of polyethylene glycol, the fluid is non-toxic and can hold up in a wide range of temperatures. The shear thickening fluid binds with hard nanoparticles of silica forming a material that is both flowable and hard truly the perfect combo for body armor.
Kevlar holds the liquid in place and, when it's hit with the force of, say, a bullet, the liquid transforms into a hard material. In conjunction with the liquid, fewer layers of Kevlar can be used to make body armor.
Liquid armor is still undergoing research and testing, but hopes are high that it will revolutionize body armor and even bomb blankets in the future.
http://smallwarsjournal.com/jrnl/art/the-history-of-body-armor-from-medieval-times-to-today https://en.wikipedia.org/wiki/Kevlar https://science.howstuffworks.com/liquid-body-armor.htm https://www.thebalancecareers.com/liquid-body-armor-3331922