Wet spinning
Introduction： Wet spinning is referred to as wet spinning. A chemical fiber spinning method in which polymer is dissolved in a solvent, and a thin stream is ejected through a spinneret, and then enters a coagulation bath to form fibers. The fiber-forming polymer suitable for wet spinning has a decomposition temperature lower than the melting point or easily changes color when heated, and can be dissolved in a suitable solvent. Synthetic fibers such as polyacrylonitrile fiber and polyvinyl alcohol fiber and man-made fibers such as viscose fiber and cupra fiber are produced by wet spinning. The cross-sections of fibers obtained by wet spinning are mostly non-circular, and have a relatively obvious core-skin structure, which is mainly caused by the solidification of the coagulation liquid.
Features: The wet spinning speed is lower, and the spinneret has more holes than melt spinning, the process flow is complicated, the number of times is large, and the production cost is higher. Generally, in the production of short fibers, porous spinnerets or graded spinnerets can be used to improve production capacity, thereby making up for the disadvantage of low spinning speed.
Process flow:
- Prepare spinning dope.
- Press the stock solution from the spinneret hole to form a trickle.
- The thin stream of raw liquid solidifies into nascent fibers.
- Fresh fiber rolls or post-processing directly.