Question

The viscose solution should have a viscosity

• A. 30--50 C-poise
• B. 30--50 poise
• C. 150--200 poise
• D. 15--20 C-poise

Hint:

Proper dope viscosity ensures smooth extrusion and uniform fibre formation in wet spinning.

Answer 1

The Correct Option is C

Step 1: Understanding viscose spinning requirements.
Viscose solution must have sufficient viscosity to form a continuous filament during extrusion through the spinneret without breaking.
Step 2: Importance of higher viscosity.
Low-viscosity solutions lead to filament breakage, while excessively high viscosity causes processing difficulties. An optimum range is required.
Step 3: Standard industrial practice.
In viscose rayon manufacturing, the viscose dope viscosity is typically maintained between 150 and 200 poise for stable spinning.
Step 4: Conclusion.
Therefore, the correct viscosity range is 150--200 poise.