Food & Drink

What is Kevlar and how does it work?

Plastic made of kevlar has a very high tensile strength. The material is bulletproof because the molecules are tightly bound and parallel to one another.

Wood, leaves, stone, tree sap, and eventually metal were all resources that Stone Age man relied on to survive. Our mattresses sometimes have metal springs and are made of straw, cotton, foam, or rubber. Typically, bed frames are made of wood or metal. Feathers make up pillows, cotton or linen make up bedclothes and pillowcases, and layers of cloth and even electrical heating elements can be found in thick blankets. And that’s it for one night of rest!

In addition to using a variety of synthetic (man-made) materials, we still use a lot of natural materials. There are many applications for plastics, which are arguably the most well-known of these synthetic materials. They are used to create polythene bags, plastic chairs, Tupperware, bottles, and drinking straws (among countless other things), whereas incredibly robust plastics like Kevlar are utilized to create aircraft parts and bulletproof materials!

What Is Kevlar?

As was previously mentioned, DuPont is a chemical company that creates synthetic material known as Kevlar. Scientifically speaking, Kevlar is basically poly-para-phenelyne-terephthalamide.

Structure Of Kevlar: What Is Kevlar Made Of?

Since Kevlar is a polymer, it has repeating units that are linked together to create a much larger molecule. Chains are formed by the repeating units in the case of Kevlar. These chains line up parallel to each other on their own, just like Liquid Crystals (used in the making of LCD TVs), showing what is known as nematic behavior. The material’s extremely high tensile strength is due to hydrogen bonds that are used to cross-link the chains.

When a highly concentrated form of the polymer is forced through a sieve, it forms long, thick fibers that are then woven into extremely stiff mats or sheets. These days, this substance is known as Kevlar.

The tensile strength of Kevlar is approximately eight times greater than that of steel wire. In essence, tensile strength is a material’s ability to resist elongation caused by a force.

For a material that is so strong, it is also fairly light in weight. It is very heat resistant (it decomposes at about 450°C), and unlike most other plastics, it does not melt or even expand when heated. Additionally, it has a high degree of cold resistance and does not crack at very low temperatures. It is extremely resistant to all types of abrasion.

There are many different types of Kevlar, but the ones that vary in quality are mainly the different grades. Kevlar K29 and Kevlar K49 are the two that are most frequently used.


Some Uses For Kevlar

Kevlar is used for many different things, as one might anticipate. Hoses, belts, and reinforcement materials are just a few of their industrial uses. It can also be used to construct tire reinforcements, support ship hulls, and components for aircraft.

Along with being used to create safety gear like gloves and motorsport helmets, it’s also used to create sports equipment like canoe hulls, race car components, snowboards, skateboards, and surfboards.

It is most well-known for being used to make lightweight military equipment like helmets and bulletproof vests. Kevlar’s special properties are also used in riding shoes, firefighting gear, body armor, and body pads.

Kevlar fibers were recently used to create a hoodie by the outdoor clothing brand Vollebak. The hoodie is literally able to withstand extreme temperatures, such as those found on Mercury’s surface or the poles of Mars. The hoodie is practically unbreakable and extremely abrasion resistant!

How does Kevlar work

The very high speed of bullets is what makes them so incredibly destructive. Although the speed varies from gun to gun, they all move fairly quickly! Bullets fired from rifles travel at much higher speeds than those from revolvers, giving them more penetrating power.

When a shot is fired, its kinetic energy is absorbed by bulletproof materials, which dissipates it so that the bullet’s speed decreases almost to zero, reducing its penetrating power and causing less damage.

A Kevlar vest’s web of sturdy fibers traps a bullet when it strikes it, absorbing and dissipating the energy and significantly lessening the bullet’s impact. This occurs as a result of the fibers being lined up so closely that it requires a lot of energy to separate them. In some cases, the vest’s durability is such that the bullets that strike it distort or bend.

Obviously, the absorption power increases with the number of layers of Kevlar sheets. Vests can be made nearly bulletproof by using different grades and numbers of layers of Kevlar.

Similar reasons also justify the use of these vests as protection from knives and daggers. Their lighter weight than the steel versions, which medieval knights once wore, is an additional benefit.

Although Kevlar is a fantastic material, it does have some drawbacks. Naturally, given how challenging it is to make, it is very expensive. New manufacturing techniques must be developed to reduce the cost of the product so that it can be used more widely and extensively. Innovations must be made to improve the compressive property of kevlar, which is also a weak point. Although its highest tensile strength is by far its greatest benefit, this also renders it incapable of flexibility, which is obviously crucial for movement when it is used to make vests or body suits.

Kevlar is a very significant material with potentially ground-breaking applications, so new discoveries and inventions are still being made about it. You might be living in a Kevlar suit for the foreseeable future simply because you have a tendency to trip and fall. It’s possible that the bumpers on your car are even Kevlar-protected.