How to distinguish aramid and polyester fibers

Aramid (Nomex is a type of aramid fiber, which is m-phenylene isophthalamide), is a new type of high-tech synthetic fiber, with ultra-high strength, high modulus and high temperature resistance, acid and alkali resistance, light weight , insulation, anti-aging, long life cycle and other excellent performance, and it is widely used in composite materials, bullet-proof products, building materials, special protective clothing, electronic equipment and other fields.

The identification method: Aramid will not continue to burn when leaving the flame, polyester will continue to burn after leaving the flame. When Polyester gets close to the flame, it is  shrunk, micro-melted, burned and melted in the flame, and there is a small spark of light. After leaving the flame, it continues to burn, and there is residue after being burnt, in the form of crisp black hard block. Also, it smells when it burns. Aramid's limit oxygen index (LOI) is greater than 28, so it will not continue to burn when it leaves the flame.

Aramid's flame-retardant properties are determined by its own chemical structure, and therefore it is a permanent flame-retardant fiber. Its flame-retardant properties will not be reduced or lost due to the use of time and washing times. Aramid fiber has good thermal stability and can be continuously used under the condition of 205°C. It can still maintain high strength under the high temperature condition of more than 205°C. Aramid fibers have a high decomposition temperature, and do not melt or drip at high temperatures. Carbonization will not happen until  the temperature is greater than 370°C.