Kapok is a natural plant fiber obtained from the kapok tree. It is smooth, unicellular, and cylindrically shaped with a thin waxy cell wall and air-filled lumen. Kapok fibers are harvested by hand from ripe seed pods, then dried, bailed, and packed. Kapok has properties including light weight, buoyancy, absorbency, thermal insulation, and biodegradability. Its end uses include mattress and pillow stuffing, clothing, life-saving equipment, construction insulation, and technical textiles.

1. KAPOK
FIBRE

2. Introduction:
• A natural, plant, cellulosic fiber.
• Obtained from seed of kapok plant Ceilbapentandra.
• Also known as silk cotton or java cotton.
• Smooth, unicellular, cylindrically shaped, twist less fibre.
• Mostly found in Africa and Central America was transported to
Asia where it was cultivated to get Kapok’s Fiber.
• Kapok fibers on their own are not suitable for spinning into
yarn, as they are too smooth, slippery and brittle.
• Kapok tree can grow up to 4 meters (13 feet) per year,
eventually reaching a height of 50 meters (164 feet).
• The fibers are 0.8 to 3.2 cm (0.3 to 1.25 inches) long.
• Composed of both lignin (a woody plant substance) and
cellulose (a carbohydrate).

3. Structure:
• Kapok fibre shows homogenous circular cross section with wide
air filled lumen having wall thickness of about 1-2µm.
• Its cell wall is thin and covered with a thick layer of wax.
• By the microscope observation kapok fibres are transparent
with characteristic air bubbles in the lumen.
• The cross section of fibres is oval to round.

4. Processing of Kapok:
Kapok harvesting process requires a lot of manpower, as each step
is done mostly by hand.
The processing of kapok starts with:
• Harvesting
• Removing hulls
• Removing seeds
• Drying
• Bailing and packing

5. Harvesting:
• The ripe unopened pods are normally harvested by knocking them
off the tree, but they can also be cut from the tree or harvested when
they fall to the ground .
Removing hulls:
• Kapok fiber is left in sunlight for drying of hulls.
• The fruits are hulled and seed and fibres were removed from the
pods by hand.
Removing seeds:
• The seeds lie loose in the floss and, with the help of some beating
they fall to the bottom of the container where they are easily
separated.

6. Drying
• Kapok fibre is dried under the sun for 3 to 5 hours for complete
drying.
Bailing and packing
• Kapok fibers are then packed in the form of bales and dispatched
for further processing.

7. Properties:
1. Appearance
Kapok fibres are lustrous, yellowish brown and made of a mix of lignin
and cellulose.
2. Fineness
0.4-0.7 denier
3. Tenacity
1.4-1.74 gram/denier
4. Elongation at break
1.8-4.23
5. Absorbency
The hydrophobic characteristics of the kapok fibre could be
attributed to its waxy surface while its large percent of lumen
contributed to its excellent oil absorbency and retention capacity.

8. 6. Thermal behavior of kapok
The heat retention of kapok was better than that of other fibres
due to the static immobile air held in the large lumen region of
kapok.
7. Light weight
8 times lighter than cotton by volume.
8. Effect of Acids
Kapok shows good resistance to alkalis and it is not damaged by
alkali.
9. Effect of Alkalis
Kapok shows good resistance to alkalis and it is not damaged by
alkali.
10. Effect of Microorganisms
Because of lignin micro organism shows no effect.

9. Chemical Composition of Kapok:
64% cellulose, 13% lignin and 23% pentose.
Advantages:
• Light weight,
• Hydrophobic and the good buoyancy effect,
• Comfortable
• Thermal insulator
• Bio degradable
Dis advantages:
• The fibres are fragile and break easily
• Not suitable for weaving or spinning
• Irritant to lungs and needs extra care during work
• Highly inflammable.

10. End uses:
• Mattress/Pillow stuffing
• Clothing
• Life-saving equipment
• construction of thermally insulated and soundproof covers
and walls,
• Technical textiles
Yachts and boats furnishing, insulating materials in
refrigeration systems
• Substitute of cotton in surgery
• By products such as Kapok seed oil.