Fibers ballistic vests

Kevlar fibers are supplied by DuPont as Kevlar-29 and 49. The former is characterized by high tensile strength and the latter by high initial modulus(4). Some Kevlar-29 end uses are in ropes and cables, which are as strong as steel at one-fifth the weight, and in ballistic vests. Some Kevlar-49 end uses are in reinforcing resins and composites for aerospace structures, boat hulls, and sport equipments. 

High modulus fibers as strong as steel but have one-fihh the weight, ideally suited as tire cord materials and for ballistic vests, e.g., Kevlar yXwaron. 

UHMWPE fibers are used in apphcations such as marine cordage and hfling slings, police and military ballistic vests, armored vehicles, cut-resistant gloves, fishing lines, and safety clothing. 

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... 

A third interesting aspect of this story is that Du Pont s aramide fiber was not specifically the result of market-driven research. When this fiber was patented in 1971 there was no commercial application in view. However, within ten years, three varieties of Kevlar fiber were commercialized by Du Pont for dozens of reinforced plastic applications in radial passenger tires, belts, in protective clothing, such as gloves or ballistic and flak vests, in ropes and cables in racing kayaks and canoes, and in commercial aircraft. Thus the Kevlar fiber by no means resulted from the functional, bottom-up, approach which is sometimes considered as a major characteristic of materials science. The aramide fiber resulted from the traditional style of industrial research which was successful in the plastic era and confirms the leadership of chemistry in materials technologies. 

Ropes, cables, coated fabrics for inflatables, architectural fabrics, and for ballistic protection fabrics. Ship to shore mooring lines are made of aramid fibers because of its resistance to saltwater corrosion. Vests made of Kevlar 29 are used by law enforcement agencies in many countries. Later we discuss this application in some detail. 

The properties of the most important LCP fibers are listed in Table 1.2. The key application areas for LCP fibers include hard armor (vehicles, helmets), soft ballistic protection (vests), cut protection (gloves), and a variety of composite uses that include honeycomb structure, pressure vessels, and rubber reinforcement. Ropes and cables find utility in the mooring of huge offshore structures such as oil-drilling platforms and the reinforcement and support of optical cables. LCP fibers also find specialty niche markets such as sails for racing yachts, specialized fishing nets, etc. 

Two major types of polymer fibers are commonly used commercially in ballistic-proof vests today ... 

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