Over the years, many improvements have been made to military and police garments to increase safety and create a bulletproof vest that is comfortable and protective. However, in the past, being safe meant a certain amount of bulk and discomfort, as well as added weight and mass for soldiers and officers who faced combat on battlefields and in urban wars. The use of Kevlar, a DuPont trademark, has made body armor lighter and easier to work with, but flexibility remains an issue. Today, there is a new substance in use called Spectra, a composite material that is stronger, lighter and more flexible than Kevlar, which is changing the look of bulletproof wear for our troops and police forces. What are the main differences between Kevlar and Spectra, and what are the great advantages of the latter?
Let’s first examine the structure of each of the two materials. Kevlar is a high-strength, high-performance fiber that, despite its many years of use in bulletproof clothing, is still not fully understood. The best description of how it is believed to work is that the molecules form into sheets which are then stacked around the center of a fiber as spokes. The idea behind using this as a bulletproof material was to stack multiple layers of the material in a weave pattern. The tissue would then “catch” the bullet allowing the fibers to break layer by layer and absorb velocity, slowing the bullet to a stop as it also blunts and flattens when it hits the material. However, this was mostly effective when the bullets were slower and had less overall velocity, making them easier to stop. Now our troops and law enforcement officials are faced with much more technically advanced weaponry with bullets that fly at higher speeds and are constructed of harder metals. This means that Kevlar vests are stretched to the maximum and are sometimes even fully penetrated by these powerful weapons. The only answer with this material is to thicken the layers of fabric, making the material even bulkier, heavier, and less flexible.
Spectra is a completely different technology. The material is approximately 40% lighter than Kevlar, making it more comfortable from the start. In addition to that, it is not a woven structure, which means that multiple layers are not necessary, further reducing weight and bulk. At the same time, Spectra is ten times stronger than steel. So what is this substance made of that makes it compete with Superman for the title of the strongest bulletproof material? The definition states that Spectra is a “thin, flexible ballistic composite made of layers of unidirectional fibers held in place by flexible resins.” These layers are then sealed between two thin sheets of polyethylene film (think plastic wrap on leftovers). Therefore, all the materials used are lightweight and extremely flexible, making movement and portability more realistic for users. At the same time, it disperses the energy of a bullet much faster over a wider area and with greater efficiency, providing much more reliable protection against the higher velocity bullets used in combat and street crimes today. So far in testing, Spectra’s performance appears to be unaffected by chemicals and moisture.
What you may not realize is that these materials are also used in everyday materials that civilians constantly work with. For example, many tires today use Kevlar in their structural composition to add a minimum of indestructibility to the material. Spectra has been used to a lesser degree in items such as “to go” shopping bags.
While Spectra is a fairly new material, and most bulletproof armor still employs the use of Kevlar, both substances are important for the safety of police officers and soldiers. As time goes by, the classic use of Kevlar will likely be replaced by the lighter Spectra material which is also stronger, especially as technology improves and allows for the creation of full body armor. The important thing is that both materials are used correctly as necessary so that the safety of troops and police forces is not compromised, and if that means sticking to proven materials, that should be the solution. Kevlar has worked for over twenty years in all forms of combat and can be counted on to do the same in the future with minor changes to the structure of tactical vests.