What are Fibre Crops?
Plant fibres are derived from plants. Plant fibres, also called fibre crops, are elongated thick-walled cells with pointed ends which consist of cellulose and may or may not contain lignin. Fibre Crops are grown for their fibres, which are used for making paper, rope, and cloth. In medical practice, they are used as a surgical dressing made up of natural or artificial materials. Fibres may be modified chemically like in viscose. There are different types of plant fibres like jute, flax, cotton, etc. Commercially, fibres are used in the textile industry for weaving the cloth, as a filtering medium, and also for insulation purposes.
Types of Fibre
Fibres obtained from various sources can be categorised as follows:
Plants fibres (Example: Jute, flax, cotton, hemp)
Animals fibres (Example: Silk, wool)
Regenerated and Synthetic fibres
i) Fibres generated from carbohydrate materials (Example: rayon).
ii) Fibres generated from protein materials (Example: Aridil from milk casein).
Mineral fibres (Example: Glass, asbestos)
Examples of Fibre Crops
Cotton
Biological Source
Cotton consists of the epidermal trichomes or hairs of the seeds of cultivated species of the Gossypium (Gossypium herbaceum, Gossypium barbadense ), belonging to the family Malvaceae.
Preparation of Absorbent Cotton
After flowering, the plant bears fruits which are known as capsules. The fruits are 3 to 5 cells. Each capsule contains numerous seeds. The hairs from which seeds are covered are known as bolls. Then these balls are collected and dried and taken to the ginning press. Various devices separate the hairs. Linters are the hairs with a short length which are used for the manufacture of absorbent cotton. While long hairs are utilised for the cloth preparation. After mixing with a soda ash solution, it is put under pressure for about 10-15 hours. It is then treated with a suitable bleaching agent after washing it with water. Then it is dried and carded into flat sheets. Finally, it is packed in wrappers. Afterward, it is sterilised by means of Gamma radiation.
Description
Colour - White (due to bleaching)
Odour - Odourless
Taste - Tasteless
Size Cotton fibres are 2.5 - 4.5 cm, in length, and 25 - 35 diameters.
Chemical Constituents
Raw cotton contains about 90% of cellulose, 7 to 8% of moisture, wax, fat, and remains of protoplasm. Purified cotton or absorbent cotton comes with 6 - 7 % of moisture and is entirely cellulose.
Chemical Tests
First, Cotton fibres are soaked in iodine water and then dried. Then the addition of few ml. of 80% sulfuric acid trichomes which assume the purplish-blue or bluish-green colour
Ammoniacal copper oxide solution dissolves raw cotton fibres with the formation of balloons. While absorbent cotton dissolves completely with uniform swelling.
Cotton is insoluble in dilute sodium hydroxide solution and hydrochloric acid. It is soluble in 66 % of sulfuric acid.
Uses
Cotton is used as a filtering medium in surgical dressings and also as an insulating material. Cotton absorbs blood, mucus, pus and it prevents wounds from infections.
Storage
Absorbent cotton should be stored in a cool place. Cotton is made friable and brittle by the bacterial contamination. The absorbent cotton should be wrapped in wrappers to avoid dust and microbial contamination. Heat and long storage make absorbent cotton non-absorbent.
Jute
Biological Source
It consists of phloem fibres of the stem of various species of the Corchorus (Corchorus olitorius and Corchorus capsularis Linn.) and Family Tiliaceae.
Chemical Constituents
The fibres are yellowish-brown in colour and contain cellulose (53%), hemicellulose (20%), and lignin (10 %).
Chemical Test
The middle lamella is highly lignified and gives a red colour with phloroglucinol and hydrochloric acid.
Uses
It is used in the manufacture of tows, padding splints, filtering, and straining mediums. Jute fibres are used for the preparation of coarse bags (Gunny bags).
Flax
Biological Source
These are pericyclic fibres obtained from the stem of the plant Linum usitatissimum belonging to family Linaceae.
Uses
The fibres were earlier used in the manufacture of lint, but at present cotton has replaced these fibres. It is used in the preparation of rugs, lace, lawn, and filtering medium.
Difference between Natural and Synthetic Fibre
Fibres are used as a raw material to make garments, clothes or any other applicational types of equipment. There are two types of fibres based upon the source of production. Natural fibres that are obtained from plants, animals or minerals and synthetic fibres that are obtained through chemical processes with the help of machines. Some of the examples of natural fibre include cotton, jute, silk, etc. And synthetic fibre includes polyester, Nylon, rayon, etc. However, there are a lot of differences between natural and synthetic fibres which are as follows:
Difference between Natural and Synthetic Fibre
Sample Questions
What are natural fibres?
What are plant fibres? give example
Differentiate between natural fibre and man-made fibre
What are the advantages of using natural fibre over man-made fibre?
Explain the type of fibre and give examples of each.
How is cotton prepared and what are its uses?
This was all about plant fibres. To learn more, access all the free resources available on the Vedantu website for the state board, CBSE, ICSE and competitive examinations.
FAQs on Plant Fibres
1. What are the Geographical Sources of Flax, Jute, and Cotton?
Geographical Source of Flax
The annual herb is cultivated in many countries like Argentina, Russia, Canada, India, Holland, and the USA. The seeds of the plant are a good source of fixed oil and mucilage which is also used medicinally.
Geographical Source of Jute
The plants producing jute are cultivated in West Bengal, in the basins of Ganges and in Assam. The jute plants grow successfully in areas having loamy alluvial soil with pH values of 6 to 8.
Geographical Source of Cotton
In the USA, Egypt and India cotton is produced commercially. It is also cultivated in various parts of Africa and South America. In India, 7 million hectares of land are under cultivation of cotton.
2. Which Fibres are obtained from the Stem of the Plant?
There are few fibres that are obtained from the stem of the plant. The base of vegetable fibres is cellulose which is a structural material in the plant world. This is the reason that plant fibres are generally made of cellulose and may or may not contain lignin. Examples include cotton, hemp, jute, flax, ramie, sisal, and bagasse, etc. Plant/vegetable fibres are obtained from plant sources such as cotton which is obtained from the seed of the cotton plant and jute which is obtained from the jute plant's stem, from the outer covering of coconut fruit from which coir is obtained.
3. What are the natural types of fibres?
Fibres, a part of the garment making material, are obtained from geological processes or through natural sources such as animals, plants or minerals. There are two types of fibres: Man-made and natural. Natural fibres are obtained from animals, plants or minerals whereas man-made fibres are produced through some processes made on the raw materials. Natural fibres are classified according to their origin, that is plants, animals, Minerals and man-made fibres include Regenerated fabrics, semi-synthetic fabrics and synthetic fabrics.
4. Give some examples of plant and animal fibres?
Fibres are very thin thread-like materials that are usually used to make garments, clothes of different articles. These fibres are obtained from natural resources like plants or animals and are referred to as natural fibres. There are various types of natural fibres, some originating from plants while some originating from animals. Examples of natural plant fibres are cotton, jute, hemp, flax, etc. And animal fibres include camel, mohair, angora, silk, wool, etc.
5. What are the uses of plant fibre?
Plant fibres are the fibres that are extracted from plants. Some of the examples of plant fibre include cotton, jute, hemp, flax, etc. These fibres are usually used in the manufacturing of biocomposites. Its properties such as non-corrosiveness, sustainability, renewability, low cost, and high structure to weight ratio, gives them more advantage than other fibres. Fibres are also used to make ropes, wood shoes, food paper, Biofuel, etc. In the medical field, plant fibres are used as a raw material to make surgical dressings.
