1. Introduction

The fiber is most often spun in to yarn or thread and used to make a soft,Breathable Textile fibre.Cotton is a natural cellulose,seed and mono-cellular ,staple fibre.Cotton was independently domesticated in the Old and New Worlds.Lint Cotton is obtain by  removing the seeds in a ginning machine and lint cotton is spun in to yarn,which is woven or knitted in to a fabric.

2. Chemical Composition

The cotton polymer is linear,cellulose polymer.The repeating unit in the cotton polymer is cellobiose which consists of two glucose units.

Cotton | Cotton Structure | Cotton Chemical Composition

Cotton consists of about 5000 cellobiose unit that is its DP(Degree of polymerization) is about 5000.Its a crystalline fibre have 65 to 70 % crystalline and up to 35% amorphous region.

Components Percentage (%)
Cellulose 94
Protein 1.3
Peptic Substance 1.2
Ash 1.2
Fat and Wax0.6
Organic acid, Sugar & others1.6

The Cotton Polymer: 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 consists of about 5000 cellobiose units that is its DP (Degree of Polymerization) is about 5000. It is very long, linear polymer about 5000 nm in length and about 0.8 nm thick.

The most important chemical grouping on the cotton polymer are the hydroxyl (-OH) groups. These are also present as methanol groups or -CH2OH. Their polarity gives rise to hydrogen bonds between the -OH groups of adjacent cotton polymers. Cotton is crystalline fibre. Its polymer system is about 65 to 70 percent crystalline and correspondingly about 30-35 amorphous.

3. Properties of Cotton
1. Physical Properties
  • Tenacity: The strength of cotton fibres is related with the good alignment of its long polymers.wet strength is more than when dry.
  • Elastic Plastic Nature: Cotton fibres are relatively inelastic in nature because of its crystalline polymer system,for that reason cotton textile wrinkle and crease readily.Hydrogen bonds holds their polymer system.
  • Hydroscopic Nature: Cotton fibre is very absorbent due to countless -OH groups,these attracts water moisture content in raw cotton is 7 to 9 % and cotton 11%.
  • Thermal Properties: Cotton fibre shows excellent resistance to thermal decomposition.It has ability to conduct heat energy. They have extremely long fibres and countless hydrogen bonds they forms.
  • Effect of light: The Visible area of  the spectrum sunlight lies between 400 and 800nm (violet to red),which is more than 340nm(uv portion of sunlight).thats why cotton is not subjected to any changes (Degredation)at all in day light.but there is  gradual loss in strength in case of prolonged exposure and the colour turns yellow,degradation period of cotton is 940 hrs.

2. Chemical Properties
  • Effect of acid: Care must be exercise when cotton comes in contact with acids(concentrated or diluted mineral acids like H2SO4 will damage cotton),this is due to acidic conditions hydrolyse the cotton polymer and glycoside 2 atoms ,which links the two glucose units to form he cellobiose unit.cellulose losses its strength as degradation proceeds.Weak organic acid like acitic acid will not damage cotton.
  • Effect of alkalies: Alkalies does not harm the cotton fibre,strong alkalies (NaOH)improves quality of cotton,this is due to the lack of attraction between the alkalies and cotton polymers.
  • Effect of bleaches: The most commonly used bleaches in cotton are sodium hypochloride (NaOCl) is a yellowish liquid bleaches at room temperature and  sodium perborate (NaBO2,3H2O) is a white powder is more effective when loundary solution exceeds 50 degree celcius.
  • Effect of micro organism: Cotton fibre can resist moths and most insects,but it can be food for fungi,do make it candidate for mildew and starchy material as a sizing promotes mildew. A widely used method of protecting cotton from attack is the application of some substances such as copper napthenate Cu(CH2)nCOO)2 and polychlorophenols that kills the micro organism.
  • Affinity for dyes: Cotton has good level of affinity of dyes(Reactive,vat and azoic dyes mostly used).
  • Resistance to perspiration: Human body may alkaline or acidis, its depends on the individuals metabolism.
  • Effect of heat: Cotton has ability to withstand moderate heat but extreme heat will cause cotton good burnt.
  • Shrinkage: Cotton fibre absorb water when it is wet and it tends to shrink as it dries.

4. Uses of Cotton Fibre
  1. The most basic use of cotton is to provide thread using cotton ginning, which they can have vast use both domestic and industrial.
  2. Cotton is used to make comfortable and breathable textile, which later on will have multiple purposes of use.
  3. By weaving cotton fiber, fabrics such as flannel, velvet, velour, and corduroy can be made by which exquisite clothing can be produced
  4. All of us in our lifetime have tried or heard about cotton candy. Guess what it is made of? Of course cotton as cotton is a good fiber corp.
  5. In the production of cosmetic and soap products, cotton is used.
  6. Pharmaceutical companies also utilize cotton in making of their product. Such as first aid kit often holds cotton.
  7. Due to its high absorbency, elasticity, purity, and hypoallergenic properties, cotton has long been a top preference in the healthcare arena.
  8. Cotton is used in the paper sector is for the creation of high excellent paper that are sought by professionals that require a difficult copy of their document to last the test of time.
  9. Although it may sound strange, cotton is used in making of Automobile-tops
  10. To make beautiful crafty cloth-bags, cotton is used so you can carry your daily essentials with you.

  1. Cotton is also used to make canvas where artists use their imagination to come up with admirable artworks.
  2. While decorating your home with beautiful looking curtains and carpets, furniture covers, cotton is of great help.
  3. The handkerchief has been around for quite a long time and is also used as a fashion item, “Gentlemen’s fashion” to be specific. Cotton makes the best looking and comfy ones.
  4. In the making of shoelaces, cotton is used.
  5. Although different alternatives are present in the apparel industry, cotton is the safest bet because it produces less waste in the production process, and most of those byproducts later can be used in other productions.
  6. The market for bedcover, sheets, pillowcases is heavily dependent upon cotton. For other home furnishings like curtains and pillows, cotton is a principal choice.
  7. Undergarments made up of cotton proves to be comfy as they are made up of breathable substances and provides greater airflow.
  8. Cotton is also used in the making of Adhesive tape to tape those party balloons to decorate your home.
  9. To make terry-cloths which are used in the process of making towels and washcloth, cotton is used.
  10. Although typewriter is almost extinct at this stage of civilization, in making of typewriter ribbons, cotton is used.

  1. Garments industry often use yarn, a long continuous interlocked fiber, in their production process.
  2. In the process of cheese making, where cheese-cloth made up of cotton is used to separate cheese custard and whey.
  3. Bandages provide the fastest solution to hold blood flow and has saved countless lives. Cotton is the primary material in the making of dressings to soak up and keep blood flow.
  4. Cotton is also used to make bookbinding to hold pages of a book together.
  5. Cotton is held as one of the key ingredients in producing certain beauty products. Mainly in two major ways, cotton is used in these regard-manufacturing items like sheet masks, makeup remover wipes, and by using cottonseed oil, which is extremely nourishing in nature.
  6. In the production of an umbrella, cotton is used to make the clothes that keep us dry from the rain.
  7. One of the specialty applications of cotton includes manufacturing flame resistant apparel. These sort of apparel are suitable for professional uses as they provide protection against potential risks attributed to high temperature and mainly flashover.

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