Textile Polyamide/Nylon Filament Commonly used nylon fibers can be divided into two categories. One is the polydiacid diamine obtained by polycondensation of diamine and diacid, and the chemical structural formula of its long-chain molecule is: Polyamide filament H-[HN(CH2)xNHCO(CH2)yCO]-OH The relative molecular weight of this kind of nylon is generally 17000-23000. Depending on the number of carbon atoms of the diamine and dibasic acid used, different nylon products can be obtained, which can be distinguished by the number added after the nylon, where the former number is the carbon number of the diamine, and the latter number is The number of carbon atoms in the dibasic acid. For example, nylon 66 indicates that it is obtained by the polycondensation of hexamethylene diamine and adipic acid; nylon 610 indicates that it is obtained from hexamethylene diamine and sebacic acid. The other type is obtained by lactam polycondensation or ring-opening polymerization, and the chemical…