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Properties of cotton mean mainly physical and chemical properties. These are here:
Physical properties of cotton: Length: 0.5-2.5 inch or 0.3-6 cm. Diameter: 16-20microns. Color: White, grey, cream. Luster: High. Dimensional stability: Good. Tenacity (gm/den): In dry state 3.0-5.0, In wet state 3.6-6.0 Elasticity: 74% recovery at 2% deformation and 45% at 5% deformation. Elongation at break: 3.0-7.0% Co-efficient of friction: 0.25. Drapability: Good. Resiliency: Low. Moisture regain: 8.5% and raised to around 25-30% at 100% Relative humidity. Specific gravity: 1.54 Chemical properties of cotton: Effects of Acid and Alkalis: Concentrated acid or hot but low concentrated acid damages cotton. Cotton dissolved in high concentrated mineral acids such as HCl, H2SO4 but high resistant to alkalis. That’s why NaOH, Na2CO3 are used for scouring of cotton. Concentrated NaOH is also used for cotton mercerizing. Effects of Bleaches: Resistance to bleach, but H2O2, NaOCl, NaOCl2, Ca(OCl)Cl are used as bleaching agents for cotton processing. Effect of heat: Cotton has an excellent resistance to degradation by heat. It begins to turn yellow after several hours at 1200C and decomposes at 1500C as a result of oxidation. It damaged at 2400C, flame at 3900C and burns in air and smell is like paper burning. Effect of organic solvents: Have resistant ability to most organic solvents such as dry cleaning agents. A little organic solvents can damage cotton. Dyeability: Have affinity to Direct, Reactive, Effect of sunlight: There is a gradual loss of strength when cotton is expressed to sunlight and the fibre turns yellow. Ultraviolet ray is harmful for cotton. Effect of weather: Acidic air spoils the strength of cotton. If cotton is stored carefully on dry condition it lasts for many years. Effect of insects: Cotton is not attacked by moth grubs or beetles. Micro-organism: Cotton is attacked by fungi and bacteria. Uses of cotton: Apparel - Wide range of wearing apparel: blouses, shirts, dresses, separates, children-wear, active wear, skirts, pants, sweaters, swimwear, suits, jackets, hosiery, neckwear. Home Fashion - curtains, draperies, throws, sheets, bedspreads, comforters, towels, napkins, table mats, table cloths. Medical and cosmetics – Bandage, wound plaster. Others - fishing nets, coffee filters, cotton paper, in bookbinding, Fire hoses, tents.
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