Views: 0 Author: Site Editor Publish Time: 2022-03-15 Origin: Site
Kevlar is the brand name of an aramid fiber material product developed by DuPont in the United States. -CONH-C6H4-NH-]- The amide group attached to the benzene ring is a para structure (the meta-structure is another product named Nomex, commonly known as fireproof fiber).
In the 1960s, DuPont developed a new type of aramid fiber composite material, Aramid 1414. This aramid fiber composite material was officially commercialized in 1972, and the product was registered as Kevlar. Models are divided into K29, K49, K49AP, etc.
Because this new material has low density, high strength, good toughness, high-temperature resistance, easy processing and forming, its strength is 5 times that of steel of the same quality. Still, its density is only one-fifth of steel (Kevlar has a density of 1.44 per cubic centimeter). Grams, the density of steel is 7.859 grams per cubic centimeter), and people have paid much attention. Because Kevlar brand product materials are tough and wear-resistant, rigid, and flexible, they have the special ability to be invulnerable. It is called the "Armored Guard" in the military.
Aramid is mainly divided into two types, "para" aramid fiber (PPTA) and "meta" aramid fiber (PMIA).
DuPont's para-aramid brand name is KEVLAR, and the meta-aramid fiber brand name is NOMEX.
In the 21st century, the composite armor of "Kevlar" laminated sheet and steel and aluminum plates have been widely used in tanks, armored vehicles, body armor, nuclear-powered aircraft carriers, and guided-missile destroyers. The composite material of "Kevlar" and ceramics such as boron carbide is ideal for the manufacture of helicopter cockpit and driver's seat. According to tests, its ability to resist armor-piercing bullets is much better than fiberglass and steel armor. To improve the survivability of battlefield personnel, people pay more and more attention to the development of bulletproof vests. "Kevlar" material is also an ideal material for making body armor. It is reported that replacing nylon and glass fiber with "Kevlar" material can at least double its protective ability under the same circumstances. It has good flexibility and is comfortable to wear. The bulletproof vest made of this material only weighs 2 to 3 kilograms and is easy to wear, so police and soldiers have adopted it in many countries.
Today's optical fibers used for transmission also use Kevlar to form a protective film. The Kevlar layer has good flexibility and protects the optical fiber from damage. The Kevlar layer is generally referred to as the buffer layer or coating layer, outside the optical fiber, inside the outer skin.
Strength: 3.6 GPa
Elongation modulus: 131 GPa
Elongation at break: 2.8 %
Long-term use temperature: 180℃
Axial thermal expansion coefficient: -2 × 10 ^ (-6) / K
Thermal conductivity: 0.048 W(m·K)
●Permanent heat resistance and flame retardancy, the limiting oxygen index Loi are greater than 28.
●Permanent antistatic property.
●Permanent acid and alkali resistance and corrosion resistance of organic solvents.
●High strength, high wear resistance, and high tear resistance.
●In the case of fire, no molten droplets are produced, and no toxic gas is produced.
●When the cloth is burned, the cloth will be thickened, and the sealing will be enhanced without breaking.
We produce Kevlar felt belts and felt tubes. For any interest, please do not hesitate to contact us.
Foshan Calm Industrial Felt Co., Ltd.
Mobile/Whatsapp/Wechat: 0086 18934300834