Kevlar is used to make many different varieties of clothing, accessories, and equipment to be resistant to cuts. Kevlar is five times stronger than steel and equalling to the same weight. Kevlar is known for its use in ballistics and stab resistance body armour. Kevlar has done its part in heroism by saving the lives of thousands of people around the world. Kevlar was invented in 1964 in a DuPort Laboratory in Delaware by a chemist named Stephanie Kwolek when she was 41. She earned a Science degree in Chemistry in 1946. She began work at DuPort research Laboratory where she conducted low-temperature experiments for preparation of polymers for the creation of highly rigid and strong petroleum-based fibres. Kwolek made a solution that caused unstable intermediates from these experiments to bond into long chains. Under these conditions, the polymers formed a cloudy fluid in contrast to the clear and sticky fluid of most polymers. Kwolek spun this cloudy fluid into extremely strong fibres that were eventually patented and marketed in 1971, seven years after it was invented, under the brand name of Kevlar. Physical Properties of Kevlar are high heat resistance, extreme strength, a density of 1.44g/cm3. The molar mass for Kevlar is 238 grams. Unlike most plastics, Kevlar does not melt; it is good at withstanding temperatures, it decomposes only at around 450oC. Low temperatures have no effect on Kevlar. DuPont found “no embrittlement or degradation” down to -196oC Kevlar can be ignited but the burning usually stops when the heat source is removed. Like many other plastics, long exposure to sunlight causes discolouration and may cause some degradation of the Kevlar fibres. Kevlar can resist sudden attacks of many different chemicals, but a long exposure to bases or even strong acids will degrade Kevlar over time. The super strong properties of Kevlar are virtually unaffected by moisture when it was tested at the DuPont laboratory under hot...
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