Man made fibre

1. To My
Presentation

2. VISCOSE RAYON FIBRE

3. Viscose is a regenerated
very fine , regular filament or
staple fibre .viscose rayon is
made by reconverting
cellulose from a soluble
xanthate from to tough fibres
by washing in acid.
What is viscose rayon fibre ?

4. Introduction
 It is the oldest regenerated cellulose fibre.
 It is biodegradable & renewable polymer.
 Common sources wood pulp & cotton lint.
 Highly purified wood pulp consists of 90-95%
cellulose called chemical cellulose & dissolving pulp.
 The process used to make viscose either continous
or batch process.

5. Characteristics of Viscose Fibre
 Highly absorbent.
 Soft and comfortable.
 Easy to dye.
 Drapes well.
 Versatile.
 It does not shrink when heated.
 It is biodegradable.

6. PROPERTIES OF VISCOSE
FIBRE
 Dry Tenacity(GPD) : 2.5 to 3
 wet tenacity(GPD) : 40 to 50% less
 Moisture Regain : 13 %
 Lusture : Light to bright
 Elasticity : Good
 Melting Point : 150%
 Elongation Percentage : 20-25%

7. Chemical structure

8. Spining bath composition
 H2SO4 : 10%
 Na2SO4 : 18%
 Glucose : 02%
 ZnSO4 : 01%
 Water : 69%

9. Cellulose unit for viscous ,n=350
Cellubiose unit for cuprammonium,n=450
Cellubiose for polynosic ,n=500
DP of Viscous rayon

10. Manufacturing Of
Viscose rayon Fibre
Raw materials , wood pulp (C6H10O5)
Alkali cellulose (C6H9O4ONa)
Cutting
Ageing
Sodium cellulose xanthate
Viscose spinning solution
Filtration and de-aeration
Ripening
Spinning and winding

11. Processing
step
Reaction
Steeping C6H9O4OH + NaOH C6H9O4. Ona +H2O
Xanthation C6H9O4. Na +CS2 C6H9O4. OCSSNa + Na2CS3
Mixing C6H9O4. OCSSNa + NaOH Viscose solution
Ripening C6H9O4. OCSSNa + NaOH C6H9O4OH + CS2 + NaOH
Spinning C6H9O4. OCSSNa + H2SO4 C6H9O4OH +CS2 + Na2SO4
Sequence of reaction viscose process

12.  Temperature and composition of the bath.
 Speed of Coagulation.
 Length of immersion.
 speed of spinning.
 stretch imparted to the filaments.
Factor affecting the quality of viscose
rayon

13. USES
Blends:
Regular rayon and high wet modulus usually blend with many fibers like
polyester,acrylic,nylon,acetate,cotton,flax,wool and ramie.
With polyester , nylon and and acrylic :
Rayon contributes absorbency,comfort,and softness when blended with them.
With cotton:
It alters appearance to create soft luster.
With wool:
It will decrease the cost.
With flax and romie:
It can help produce appearnce that are typically associated with linen like
fabrics.

14. Some products of Viscose rayon fibre