1.Aramid fiber equipment
The full name of aramid fiber is aromatic polyamide fiber. It is a linear polymer composed of aromatic groups and amide groups. It has excellent mechanical properties, stable chemical structure, ideal mechanical properties, ultra-high strength and high modulus. , high temperature resistance, acid and alkali resistance, light weight, wear resistance and other excellent properties. It has been widely used in fields such as bulletproof protective equipment, aerospace, construction and electronic equipment.
However, aramid fiber also has two major disadvantages
(1) Aramid fiber has poor UV resistance. Ultraviolet radiation (sunlight) causes degradation of aramid fibers. Therefore, a protective layer is required, which can be a topcoat or a layer of material, for example, aramid threads are often enclosed in a protective layer.
(2) Aramid fiber has relatively high hygroscopicity (up to 6% of its weight), so aramid fiber composite materials need to be properly protected, such as topcoats are usually used to reduce hygroscopicity. Additionally, the use of certain types of aramid reduces the water absorbency of the composite when it is exposed to water, such as Kevlar 149 or Armos.
2.PE fiber equipment
PE actually refers to UHMW-PE, which is ultra-high molecular weight polyethylene. It is a high-performance organic fiber developed in the early 1980s. Together with carbon fiber and aramid, it is known as the three major high-tech fibers in the world today. It has ultra-high stability and is extremely difficult to degrade, causing serious environmental pollution. But it is precisely because of this characteristic that it becomes an ideal material for making body armor. In addition, it is resistant to low temperature, UV light, and water.
In terms of preventing low-speed bullets, the bulletproof performance of PE fiber is about 30% higher than that of aramid; in terms of preventing high-speed bullets, the performance of PE fiber is 1.5 to 2 times that of aramid. It can be said that the shortcomings of aramid fiber have become the advantages of PE fiber, and the advantages of aramid fiber have become better on PE fiber. Therefore, it is an inevitable trend for PE fiber to replace aramid in the field of protection.
Of course, PE fiber also has shortcomings. Its temperature resistance level is far inferior to aramid fiber. The use temperature of PE fiber protection products is within 70°C (which can meet the requirements of the human body and equipment, that is, the temperature resistance requirement of 55°C). Beyond this temperature, the performance declines rapidly. When the temperature exceeds 150°C, the PE fiber will melt, and the aramid fiber The fiber can still maintain good protective properties in an environment of 200°C, and does not melt or decompose at 500°C; when encountering high temperatures above 900°C, it will be directly carbonized to form a heat insulation layer. These are not available in PE fiber protective products and have become the unique advantages of aramid products.
Post time: Oct-13-2023