Polyvinyl Alcohol (PVA) is one of the most versatile water-soluble Polymers, PVA can be quickly dissolved in water to form a stable colloid, performance between Plastics And Products.Polyvinyl Alcohol Fiber is one of the important varieties of synthetic fibers, and its regular product is polyvinyl alcohol formaldehyde fiber, which is referred to as vinylon or Vinylon in China. The products are mainly short fibers. Polyvinyl Alcohol Fiber is mainly used for blending with cotton, woven into a variety of cotton fabrics. In addition, it can also be blended with other fibers or pure spinning, weaving all kinds of woven or knitted fabrics. The performance and appearance of polyvinyl alcohol filament is very similar to that of natural silkworms, and it can be used to weave satin fabrics. However, because of its poor elasticity, it is not easy to dye, so it can not be made of high-level clothing. In recent years, with the development of polyvinyl alcohol fiber production technology, its application in industry, agriculture, fishery, transportation and so on is expanding.
Ordinary polyvinyl alcohol has a high degree of polymerization and alcoholysis, in the flexible main chain contains a large number of hydroxyl, intermolecular and intramolecular formation of a large number of hydrogen bonds, physical crosslinking points, high density, resulting in polyvinyl alcohol fibers with high crystallinity, is not conducive to the penetration of water molecules. If you improve the water solubility must weaken the affinity between the macromolecules, there are two general methods: reduce the hydroxyl content and increase the distance between the hydroxyl group. Polyvinyl alcohol with the increase in degree of polymerization, fiber hydrophobicity increases, the water solubility temperature increases accordingly. Therefore, the use of low polymerization degree of polyvinyl alcohol for spinning, can get a lower water soluble temperature of the fiber. However, the polymerization degree decreases, the spinnability becomes worse. Japanese patents use low polymerization degree (less than 800) components and high polymerization degree (more than 1000) components for co-spinning, the resulting fiber spinning and water solubility are ideal.
The degree of alcoholysis of polyvinyl alcohol also has a great influence on the water solubility of fibers. The residual ethylcool group will hinder the close arrangement of macromolecules, so that the crystallinity will be poor, and the water solubility temperature will be lowered. However, the presence of residual ethylcool group will affect the tensile properties of primary fibers and increase the number of broken filaments and hairy filaments, and will also affect the coloring of fibers, so the degree of alcoholysis of water-soluble polyvinyl alcohol should be an appropriate level.
