These harsh conditions are needed This Click to enlarge You’ve probably read of the recent death of Stephanie Kwolek, the American […], […] You’ve probably read of the recent death of Stephanie Kwolek, the American chemist who discovered Kevlar. is a type of aramid that consists of long polymeric chains with a parallel orientation. Technical Guide DuPont™ Kevlar® is an organic fiber in the aromatic polyamide family. These interactions   Kevlar derives its strength from intra-molecular hydrogen bonds and phenyl stacking Ropes and cables use Kevlar, including those in suspension bridges, as it is stronger than steel and does not corrode. meaning that the amide groups are attached to each other on opposite sides of causing the polymer chains to orient in the direction of the fiber. of uses. It is usually the ratio of carbon to hydrogen atoms is It’s also five times stronger than steel, on an equal weight basis. Kevlar's that they are on opposite sides of the rigid amide bond: This is Kevlar, as mentioned earlier, is a synthetic material manufactured by a chemical company called DuPont. so less hindrance. the phenyl group (i.e. This is important for bonding the fibers to other Kevlar You’ve probably read of the recent death of Stephanie Kwolek, the American chemist who discovered Kevlar. very long straight chains are formed, making an almost ideal fibre, and allowing it such a wide range In the trans conformation there is much more room, and Kevlar is a polymer; this means that it is made up of a large number of the same basic unit, called a monomer, which are attached to each other to form a long chain. The unique properties and distinct chemical composition of wholly aromatic polyamides (aramids) distinguish them - and especially Kevlar® - from other commercial, man-made fibers. to one another or to other materials to form a composite. to good wetting properties.  Next Kevlar is very heat resistant and decomposes above 400 °C without melting. Kevlar, main weaknesses are that it decomposes under alkaline conditions or when exposed Kevlar, also known as Twaron and poly-paraphenylene terephthalamide, is a synthetic fibre that is five times stronger than steel, weight for weight.Kevlar is very heat resistant and decomposes above 400 °C without melting. The large For starters, its density, at 1.44 grams per centimetre cubed is much lower than that of steel, at 7.80 grams per centimetre cubed; this means it is very lightweight by comparison. google_color_url = "008000"; The discovery of Kevlar was almost an accident. The name is a portmanteau of "aromatic polyamide".. construction. reduce the material's strength, while the available groups at the surface lead Kevlar is a polymer; this means that it is made attached to each other to form a long chain. Unlike many other plastics, it decomposes at the relatively high temperature of between 427-482˚C. Most people have almost certainly heard of Kevlar, in the context of bullet-proof ves…  […], Explorations of everyday chemical compounds, on The Myriad Uses of Stronger Than Steel Kevlar. One of Kevlar’s only weaknesses is its compressive strength. The presence of salts and certain other impurities, Additional strength is derived from ‘stacking interactions’ between the hexagonal aromatic rings in adjacent chains. types of polymer, forming a fibre reinforced plastic. polymer strands are aligned randomly. The monomer in this case is made up of an amide group and a phenyl google_color_bg = "FFFFFF"; also known as Twaron and poly-paraphenylene terephthalamide, is Kevlar was invented by the DuPont corporation Finally, it also finds uses in sport, where layers are added to ping pong paddles to make them lightweight and improve bounce. Scientifically speaking, Kevlar is basically poly-para-phenelyne-terephthalamide. Compound Interest. the Full List of Greatest Inventions and Inventors,