Structural characteristics of nylon staple fibers

  1. Molecular structure:
  Main chain structure: The main chain of nylon staple fibers contains repeated amide groups (-NHCO-). This amide group enables strong hydrogen bonds to be formed between molecules, and the hydrogen bonding gives nylon staple fibers higher strength, wear resistance and good heat resistance.
  Side chain structure: Its side chains are relatively simple, usually some smaller alkyl groups or other simple groups. The side chain structure has a certain influence on the solubility, water absorption and other properties of nylon staple fibers. For example, shorter side chains may make nylon staple fibers more soluble in certain solvents; while slightly longer side chains may increase the hydrophobicity of the fibers.
  Aggregate structure:
  Crystallinity: Nylon staple fibers have a high degree of crystallinity. In the crystalline region, the molecular chains are arranged regularly and tightly, which makes the fibers have higher strength and hardness in the macroscopic sense, and also makes them have better dimensional stability. However, high crystallinity may also lead to a relatively low toughness of the fiber, and brittle fracture is prone to occur when subjected to large external force impact.
  Orientation: During the production and processing, the molecular chain or crystal structure of nylon staple fibers tends to be oriented in a certain direction. The increase in orientation can significantly enhance the strength, modulus and other properties of the fiber in the orientation direction. For example, in the textile process, a specific process can make the orientation of nylon staple fibers in the fabric more orderly, thereby improving the overall performance of the fabric.
  2. Morphological structure:
  Cross-sectional shape: The cross-sectional shape of nylon staple fibers is usually more regular, mostly circular or approximately circular. This shape allows the fiber to withstand stress more evenly when subjected to force, and is not prone to local stress concentration, thereby ensuring the overall strength and stability of the fiber.
  Longitudinal appearance: From the longitudinal appearance, the surface of nylon staple fibers is relatively smooth, and the friction between fibers is small. This feature allows nylon staple fibers to be relatively easy to comb and arrange during processing, such as spinning, weaving and other processes, to improve production efficiency; at the same time, when blended with other fibers, they can also be better combined with other fibers to give full play to their respective advantages.