Knowledge of bulletproof material-UHMWPE

Ultra high molecular weight polyethylene fiber (UHMWPE), also known as high-strength PE fiber, is one of the three high-tech fibers in the world today (carbon fiber, aramid fiber, and ultra-high molecular weight polyethylene fiber), and is also the toughest fiber in the world. It is as lightweight as paper and as hard as steel, with a strength 15 times that of steel, and twice that of carbon fiber and aramid 1414 (Kevlar fiber). It is currently the main material for manufacturing bulletproof vests.
Its molecular weight ranges from 1.5 million to 8 million, which is dozens of times that of ordinary fibers, which is also the origin of its name, and it has extremely excellent performance.

PE

1. The structure is dense and has strong chemical inertness, and strong acid-base solutions and organic solvents have no effect on its strength.
2. The density is only 0.97 grams per cubic centimeter, and it can float on the water surface.
3. The water absorption rate is very low, and it is generally not necessary to dry before forming and processing.
4. It has excellent weather aging resistance and UV resistance. After 1500 hours of exposure to sunlight, the fiber strength retention rate is still as high as 80%.
5. It has excellent shielding effect on radiation and can be used as a shielding plate for nuclear power plants.
6. Low temperature resistance, it still has ductility at liquid helium temperature (-269 ℃), while aramid fibers lose their bulletproof effectiveness at -30 ℃; It can also maintain excellent impact strength in liquid nitrogen (-195 ℃), a characteristic that other plastics do not have, and can therefore be used as low-temperature resistant components in the nuclear industry.
7. The wear resistance, bending resistance, and tensile fatigue performance of ultra-high molecular weight polyethylene fibers are also the strongest among existing high-performance fibers, with outstanding impact resistance and cutting toughness. A ultra-high molecular weight polyethylene fiber that is only a quarter the thickness of hair is difficult to cut with scissors. The processed textile must be cut using a special machine.
8. UHMWPE also has excellent electrical insulation performance.
9. Hygienic and non-toxic, can be used for contact with food and drugs. Compared with other engineering plastics, ultra-high molecular weight polyethylene fibers mainly have shortcomings such as low heat resistance, stiffness, and hardness, but can be improved through methods such as filling and cross-linking; From the perspective of heat resistance, the melting point of UHMWPE (136 ℃) is generally the same as that of ordinary polyethylene, but due to its large molecular weight and high melting viscosity, it is difficult to process.


Post time: Apr-30-2024