All polymers cannot be used for textile purpose. The following principles/characteristics should be there in the polymers to use them for textile purpose.
Long
Flexible
Linear
Capable of orientation
High molecular mass
Hydrophilic
Resistant to chemicals
Ability to form high melting point polymer system
1. Long:
The polymer chain must be longer to achieve more strength in the fiber by holding the crystalline regions together. A polymer length of 100 nanometers is required to produce a fiber with adequate strength. Polymers of such lengths can readily be oriented. There will be inter polymer forces of attraction if the polymers are oriented. This leads to form a cohesive polymer system, hence, fibers.
Longer chain α more strength
2. Flexibility:
The polymer should be linear flexible with high degree of symmetry.
3. Linear:
The polymers must be linear means should not be branched. Linear polymers allow adequate polymer alignment/attraction to give a cohesive polymer system. Branched polymers cannot pack close together which prevents the formation of crystalline regions thus resulting in a weak fibre. So the polymers must be linear.
4. Capable of orientation:
The polymers must be capable of being oriented. A high degree of orientation gives a great tensile strength in the fiber. There are two forms of polymer orientation. They are amorphous and crystalline. In the operation of drawing, which stretches the extruded and coagulated filament causes the polymers to orient themselves.
5. High molecular mass:
The molecular mass must be very high.
6. Hydrophilic:
It must be hydrophilic because amorphous and polar nature of fiber results in moisture absorbance property. Crystalline polymer nature of fiber restricts the passage of water, any molecules in to the fiber structure which leads to poor moisture absorbency.
7. Resistant to chemicals:
The polymers should be chemically resistant against sunlight, perspiration, laundry and dry-cleaning liquids.
8. Ability to form high melting point polymer system:
The fibers must have high melting point to withstand the extreme heat conditions and it needs to be above 2250 c for the usage of apparel and textile manufacturing.
The textile fibers which meet all the above requirements are cotton, viscouse, flax, nylon, polyester, silk, wool, acrylics and acetates.
The fibers like polypropylene, polyethylene and chloro fibers which are restricted in their textile use because they do not meet the requirements like hydrophilic, orientation capability and ability to form high melting point.
The polymers of natural fibers like cashmere, mohair and angora fulfill the above requirements largely but because of their expensive nature and scarcity, they are not used frequently.
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