Wet spinning:
In wet spinning, a suitable solvent is used to prepare the fiber-forming solution and another coagulant is used in the coagulating bath. The solution is extruded through a spinneret and in contact with coagulant cellulose is regenerated. Here a Working Flow Chart of Wet Spinning Process.
Working Flow Chart of Wet Spinning Process
At first solid polymer and the suitable solvent is dissolved in a solution vessel.
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The solution is then heated in the heat exchanger.
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The solution is passed/extruded to spinneret which immersed in a coagulation bath/spin bath by pump.
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The polymer is chemically regenerated and it is converted into the filament of solid form.
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The filament is converged and wound on the bobbin.
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The wended filament is then drawn and finally, it is washed & dried and is also wound on a suitable package.
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Delivery
This is the oldest, most complex, and also the most expensive method of man-made yarn manufacture. This type of spinning is applied to polymers that do not melt and dissolve only in non-volatile or thermal unstable solvents.
Wet Spinning process:
- In wet spinning, a non-volatile solvent is used to convert the raw material into a solution.
- The solvent is extruded through the spinneret either by simply washing it out or by a chemical reaction between the polymer solution and a reagent in the spinning bath.
- After extrusion, the solvent is removed in a liquid coagulation medium.
- Finally, the filament yarn either is immediately wound onto bobbins or is further treated for certain desired characteristics or end-use.
Example: Wet spinning is used in the production of aramid, Lyocell, PVC, Vinyon – PVA,, viscose rayon, spandex, acrylic, modacrylic fibers, and so on.
Advantages: Large tows can be handled
Disadvantages: Slow (70-150 yds /min), Washing to remove impurities, Solvent, and chemical recovery
Author of this Article: Muhammad Ibrahim Khalilullah Department of Textile Engineering Daffodil International University Email: ibrahim23-3123@diu.edu.bd