Friday, March 27, 2020

KAPOK FIBRE, CHEMICAL COMPOSITION,AND USES, USES, AND PROPERTIES


KAPOK FIBRE:

BOTANICAL CLASSIFICATION OF KAPOK PLANT:

Botanical name - Ceiba pentandra (L.) Gaertn.


Kapok is the most commonly using name for the tree and may also refer to the cotton obtained from its seed pods. The tree is also known as the Java cotton, Java kapok, Silk cotton or ceiba. It is a sacred symbol in Maya mythology.

CHEMICAL COMPOSITION OF KAPOK FIBRE:

Chemical composition of kapok fibre is given below table:



KAPOK GROWING COUNTRIES

Kapok tree grows in forest of following countries:

• African countries: Nigeria, Mozambique, Tanzania.

• Asian countries: Sri Lanka, Indonesia, Thailand,Vietnam, Philippines.

• South American countries: Brazil, Ecuador, Costa Rica, Peru .

INFORMATION ABOUT KAPOK TREE

• This tree can grow up to 100 metres hight.

• This tree  can be alive for  300 years.

• The trunks of kapok can be reached to 3 metres of diameter.

• Kapok tree doesn't get damaged during kapok fibre harvesting.

• The kapok tree doesn't require insecticides and artificial irrigation.

• It has the lowest specific gravity among all natural fibre existing in the world.

• Since kapok fibres are covered with a thin film of wax that prevents insects and tiny organisms.

• Kapok is a fully ecological fibre.

• It has good insulating properties. In winter it keeps the warmth in, while in summer it prevents the heat.

• It is used for acoustic and thermal insulation.

• Kapok's flotation ability is 14 times better than that of cork.

• Kapok is recommended for people who are allergic to dust mites, since kapok fibre contains a substance that dust mites dislike and therefore they do not breed in it.

• HARVESTING OF KAPOK FIBRES:

To obtain kapok fibre, the fruits are harvested when fully ripe and mature. Ripeness is decided by the fruit colour changing from green to brown and the surface possibly becoming wrinkled. The fruits are normally harvested by knocking them off the tree before. Trees normally start to bear fruit when they are 3–8 years old.

• Yield:

“A fully developed tree may yield 330–400 fruits per year under optimum conditions”. Almost 15–18 kgs of fibres and 30 kgs of seed get obtained. A satisfactory average annual fibre yield is about 450 kg/hectare , whereas about 700 kg/hectare  is considered very good.

• Handling after harvest:

The fruits are hulled as soon as possible to obtain kapok fibre after harvesting. The drying is carried out in dry air or with fans in cage-like structures. The seeds lie loose in the floss, and therefore de-seeding is easy. They are usually separated from the floss by beating. The quality of kapok fibre is judged by fibre length, freedom from seeds and foreign matter, moisture content, colour, smell and lustre. Excessive pressure should not be used when kapok is baled. Excessive baling pressure can destroy the elasticity and diminish the quality of the fibre.

• INDIAN KAPOK:

Floss  from the simal cotton tree (Bombax malabarica), native to India, has many of the qualities of the Java type but is more brownish yellow in colour and less resilient. Immersed in water, it supports only 10 to 15 times its own weight.

PHYSICAL PROPERTIES OF KAPOK FIBRE

Physical properties of kapok fibre are given below:

• Individual kapok fibers are 1 cm. to 1.5 cm. in length.

• Under a microscope, kapok fibers present a long narrow cell with frequent folds. Its cell has thin walls and a hollow structure. Its walls form a smooth, closed tube with a large cavity called a lumen.  Each kapok fiber is coated with a waxy substance called cutine. The cutine and lumen are thought to give kapok its buoyancy.

• The total dry matter of ripe fruits, by weight, is composed of 48% shell, 21% fibre, 25% seed and 6% placenta.

• Kapok fibre cells are (8–)19–22(–35) mm long and (10–)19–20(–30) μm wide.smooth, transparent, cylindrical, with a wide lumen and thin walls. Kapok fibre contains about 43% α-cellulose, 32% hemicellulose, 13–15% lignin and 1% ash.

It is resilient, elastic, light (8 times lighter than cotton), water-repellent and buoyant (5 times more than cork). In an uncompressed state, it can support 20–30 times its own weight in water, because when the fibre is immersed in water, the lumen only partly fills with water and contains many air bubbles. Kapok fibre has a low thermal conductivity and very good sound-absorbing properties.

 A disadvantage is its high inflammability, but techniques have been developed to make it non-flammable.

In its natural form, kapok fibre cannot be spun, because of the smoothness of the outer surface. However, techniques have been developed to make spinning possible.

The fibre is long-lasting and is not attacked by fungi or pests. White-coloured fibre is preferred.

Kapok fibre is irritating to the eyes, nose and throat, and workers exposed to kapok dust for long periods may develop chronic bronchitis. People involved in processing of kapok fibre are advised to wear protective masks. Because of the irritant fibres and the spreading root system, the tree is less suitable as shade or wayside tree.

USES OF KAPOK FIBRE

Uses of kapok fibre is given below:

• Kapok fibre is used for stuffing cushions, pillows and mattresses, and for insulation, absorbent material and tinder.

• The fibre may also have potential as a biodegradable alternative to synthetic oil-sorbent materials, due to its hydrophobic-oleophilic properties.

• The flowers are an important source of nectar and pollen for honeybees.

• Eco Filling and fibre is used as stuffing in toys, dolls, cushions, pillows, pet bedding, doonas , teddy bears, upholstery and home wares.

• Eco friendly fibres replace the need for traditional polyester stuffing derived from 100% chemicals. Eco-friendly literally means earth-friendly or not harmful to the environment.
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