Introduction:
Banana is a natural, lignocellulosic bast fiber that is obtained from the pseudostem of the banana plant. It comes under the “Musa sapientum” species. These are grown in 135 countries and majorly in India, China, Philippines, Colombia, Indonesia, Ecuador, and Brazil and grow best in tropical countries. The global production of bananas was 113.9 million tons in 2017. About 1 kg of fiber is produced from the 37 kg of stems.
Processing of banana fiber:
Banana fiber can be extracted in 3 ways. They are manual, chemical, and mechanical. But the mechanical way is best to obtain good quality and quantity of fiber.
Harvesting: 25 pseudo stems may produce from a single plant. After 18 to 24 months from the plantation, stems get matured and ready to be harvested.
Tuxing:
Separation of ribbons of layers from the layers of Pulp is called tuxing and these ribbons are also called tuxies.
scraping:
As soon as harvesting and tuxing are done, extraction of fibers from the pseudostems can be done by inserting the stems in a decorticator machine as it strips the bark, stalk, wood, and skin. Stripping is referred to as the removal of non-fibrous material like pulp from the fiber bundle and gives the fine fiber as output.
Degumming:
The fiber which is produced by decorticator machine contains gum, non-fibrous cell as these are not soluble in water and must be extracted before the fiber is mechanically spun into yarn. The primary step in the degumming process is to boil the fibers in aqueous alkaline solution. The second step is to wash the fibers with water for neutralization. The third step is to bleach the fiber with hypochlorite or hydrogen peroxide. The fourth step is to wash the fiber with water for neutralizing and oiling with a sulfonated hydrocarbon.
Types of banana fiber:
Inner-peel banana fiber: It is very soft like silk. It's reasonably delicate and expensive to produce.
Outer peel banana fiber: It is a rough and coarse fiber.
Banana cotton: high-grade outer-peel banana fiber is also called banana cotton. The texture is similar to cotton.
Banana silk: it’s nothing but inner-peel banana fiber.
Chemical composition of banana fiber:
Cellulose (%): 60-65
Hemi cellulose (%): 6-19
Lignin (%): 5-10
Pectin (%): 3-5
Extractives (%): 3-6
Ash (%): 1-3
Properties:
Dia(μm): 80-250
Length(mm): 1000-5000
Cell Aspect Ratio: (l/d) 150
Moisture content (%): 10-11
Moisture regain: 9.8 to 12
Tensile Strength (Mpa): 529-914
Initial modulus (Gpa): 7.7 to 20.0
Specific Tensile Strength (Mpa): 392-677
Young’s Modulus (Gpa): 27 to 32
Specific Young’s Modulus (Gpa): 20 to 24
Failure Strain (%): 1-3
Density (gm/cc): 1.35
Tenacity: 29.98 gm/Deniar
Average Fineness: 2400Nm
Microfibrillar angle(degree): 10±1
Specific gravity: 0.9
Moisture regain: 13.00%
Elongation: 10.35%
Features of banana fiber:
It is a strong fiber with smaller elongation.
It has a shiny appearance.
It is lightweight.
It has strong moisture absorption quality so that it absorbs and releases moisture very fast.
It is biodegradable.
Banana fiber appearance is similar to bamboo and ramie fibers.
Uses of banana fiber:
It is used for making bags, purses, mobile phone covers, doormats, ropes, cushion covers, neckties, rugs, curtains, and yoga mats.
It is used for apparel and home furnishing.
It is used for composite materials as a replacement for fiberglass.