Kevlar Helmet

Some body armor is available from civilian markets (i.e., Kevlar chain saw leggings). Kevlar helmets, flak vests (not the old ballistic nylon ones, but Kevlar), and groin aprons are available at Army surplus stores in states where they are not illegal. Kevlar gloves, not included in the above list because they were not available at the time this list was developed, are now available from safety supply houses and should be used. They can be lined with Nomex gloves for further protection from fire. Summer Nomex flying gloves are also available at surplus stores and provide the flexibility necessary for fine dexterity. 

The initial meshes for the Kevlar helmet with the 9mm FMJ before impact (Tham et al., 2008). 

Originally developed for tyre cords, Kevlar-type materials have also become widely used in composites. Uses include filament-wound rocket motors and pressure vessels, metal-lined Kevlar-overwrapped vessels in the space shuttle, boat and kayak hulls, Kevlar-epoxy helmets for the US military, and as one of the reinforcements in composite lorry cabs. 

The diaminobenzenes are made from benzene by a combination chlorination-nitration route although para-phenylene diamine is also made directly from aniline. orr/to-Phenylene diamine is widely used for the preparation of biologically active compounds such as fungicides and veterinarian medicines. The mera-diamine is used in fire-retardant textile fibers ( Nomex ) while the / ara-diamine finds use in high-strength textile fibers used for bullet-proof vests, sails, army helmets, and other types of fiber-reinforced plastics ( Kevlar ). 

Figure 4.29 (a) A helmet reinforced with Kevlar aramid fiber and a bullet resistant vest made of Kevlar aramid fiber. 

Kevlar fibers are both strong and stiff and used to make bulletproof vests and protective helmets as illustrated in Figure 27.3. 

Police and the military depend on body armor and helmets made of Kevlar fibers. Kevlar protective equipment is more effective than steel, yet far lighter in weight. 

A major use of Kevlar is in rigid and soft body armour protective applications. Kevlar fabric is bullet and fragment resistant, lightweight, flexible and comfortable, has excellent thermal properties, is resistant to cuts and chemicals and is flame resistant and self-extinguishing. The uses include bulletproof vests, chainsaw leg protection and military uses for helmets and armoured vehicles, cargo containers, armour shields and cockpit doors. 

The chemistry of these polymers was extended to terphthaloyl chloride and p-phenylenediamine, resulting in the commercialization of Kevlar fiber. Kevlar (structure shown below) is ideally suited for ballistic vests and high impact helmets because of its strength and the fact that it is as strong as steel but at one-fifth the... 

Initially, Kevlar was used in car tires as reinforcement for the elastomeric matrix (rubber) however, nowadays the most widely known appHcation of Kevlar/epoxy is in body armor [27]. Other uses include fireproof suits for firefighters, gloves, and helmets [28]. Their high strength-to-weight ratio makes them more suitable for use as reinforcement, for example, in composite materials primarily where flexure properties are important, such as aircraft wings [29]. 

Kevlar—A synthetic yellow-brown fiber of very high tensile strength, woven into bulletproof vests, molded into solid sheets of lightweight armor (from aircraft to helmets). Kevlar is the brand name from DuPont used in bulletproof jackets. 

Today, DuPont sells hundreds of millions of dollars worth of Kevlar every year. Kevlar is particularly well known for its use in bulletproof vests. With this application alone, Kwolek s discovery has saved thousands of lives. In addition, Kevlar is used to make helmets, radial tires, brake pads, racing sails, suspension bridge cables, skis, and high-performance hiking and camping gear. 

Figure 13.32 The formation of Kevlar , similar to the formation of nylon 6,6. Kevlar can be molded into shapes such as helmets. 

Kevlar is used for life protection by finding its application in bullet proof vests, helmets, property protection panels, vehicle protection, and strategic equipment shielding due to its high tenacity, high energy dissipation, low density and weight reduction, and comfort. 

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