An Overview of Cotton Fiber

Cotton:
This vegetable natural fibres comes from a substance surrounding cotton plant seeds. Cotton fiber is the first used fiber all around the world The chemical structure is constituted by 85% of pure cellulose. Its cross section is bean shaped.

Cotton Fiber

Physical Properties of Cotton:

• Thickness : micronaire value from 3 to 6
• Color : white
• Length : short fiber
• Density : 1.5 g/cc
• Tenacity : medium to good, 26 to 43 cN/tex
• Moisture regain : 8.5% (at 65% of moisture and 20°C)
• Elongation : 3.5 to 7.5 %
• Flame reaction : rapidly flammable

Characteristics of Cotton:

1. Good moisture absorbency
2. Non-allergic
3. Good heat resistance
4. Good washing endurance (can be boiled and chlorinated)
5. Soft feel
6. Shrinkage tendency
7. Crimping tendency
8. Medium dyeing fastness

Macro Structure of Cotton Fiber:
Under a microscope, a cotton fiber appears as a very fine, regular fiber. It ranges in length from about 10mm to 65 mm, depending upon the quality of the fiber. Cotton is a very fine fiber with little variation in fiber diameter; compared with wool for instance, its fiber diameter is not considered as critical a fiber dimension as its length. The fiber length to breadth ratio of cotton ranges from about 6000:1 for the longest and best types, to about 350:1 for the shortest and coarsest cotton types. The greater this ratio, the more readily can the cotton fibers be spun into yarn. Cotton fibers vary in colour from near white to light tan.

Structure of Cotton fiber

Polymer System of Cotton Fiber:
The cotton polymer is a linear, cellulose polymer. The repeating unit in the cotton polymer is cellobiose which consists of two glucose units. The cotton polymer system consists of about 5000 cellobiose units, that is its degree of polymerisation is about 5000. It is a very long, linear polymer, about 5000 nm in length and about 0.8 nm thick. Cotton is a crystalline fiber. Its polymer system is about 65 to 70 per cent crystalline and, correspondingly, about 35-30 per cent amorphous. Therefore, the cotton polymers are, in the main, well oriented and probably no further apart than 0.5 nm, in the crystalline regions.

End Uses of Cotton Fiber :

• Fluff: absorbent cotton, padding. 

• Clothing: pants, shirts, blouses, dresses, suits, jackets, undergarments. 

• Home furnishings: Bed sheets , pillow covers, mattress, curtains, towels, table cloths, napkins.