Uploaded by Jaber Husaine

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Abstract:
Banana is one of the important fruit crop cultivated in tropical parts of the world. Banana
farming generates huge quantity of biomass all of which goes as waste and the above ground
parts like peduncle are the major source of fiber. Banana fibre is a good alternative to all the
synthetic and natural fibres. Banana fibre is eco-friendly, chemical-free, nontoxic and odour
free. The natural coolant and medicinal property of banana fibres helps in the health of its user
and is 100% safe as no harmful chemicals and colours are used. Mechanical properties like tex
and fiber diameter decides the fineness. Banana plant is available throughout Thailand and
Southeast Asian, India, Bangladesh, Indonesia Malaysia, Philippines, Hawaii, and some Pacific
islands.
Introduction:
Banana plant or plantain plant not only gives the delicious fruit but it also provides textile fiber
the banana fiber. Banana fiber is natural fiber. Natural fibers present important advantages such
as low density appropriate stiffness and mechanical properties and high disposability and
renewability. Moreover, they are recyclable and biodegradable. There has been lot of research on
use of natural fibers in reinforcements. Banana fiber a ligno-cellulosic fiber obtained from the
pseudo-stem of banana plant is a bast fiber with relatively good mechanical properties. Banana
plant is a large perennial herb with leaf sheaths that form pseudo stem. Its height can be 10-40
feet (3.0-12.2 meters) surrounding with 8-12 large leaves. The leaves are up to 9 feet long and 2
feet wide (2.7 meters and 0.61 meter).
Banana fiber Extraction Process:
The knowledge of extracting fiber and paper from banana was well known since the 13th
Century when Japanese processed it. However, it was a time-consuming and costly process
where banana stems were first boiled in lye to soften them and then prepared from shredding to
extract yarn. They produced banana fibers of varying degrees of softness yielding yarns and
textiles with differing qualities for specific uses.
The outer sheath from the banana stem is first peeled off the inner layers are flattened and fibers
are stripped off either manually or through machines. Heaps of banana stems are piled up near at
the processing unit and workers begin slicing the banana stems into thin strands. These sliced
stem pieces are then passed through the machine on the fixed platform that separates the gummy
lignin and water content from it. The shredded fiber is then cleaned and dried in the sun before
being bundled into yarn that makes notepads, stationery items, lampshades, and handicraft.
Some component of banana fiber machine:
1. Machinery is developed by German technology with 1 H.P. single phase motor.
2. Easy to Mobilize (Portable)
3. Ladies can operate, less maintenance, and safe to operate.
4. User friendly & Economic.
5. Clean work atmosphere.
6. Fifty times increase in fiber production compared to manual process.
7. Superior quality fiber in terms of length, softness and color.
Characteristics of Banana Fibers:
Banana fiber has its own physical and chemical characteristics and many other properties that
make it a fine quality fiber.
 Appearance of banana fiber is similar to that of bamboo fiber and ramie fiber but its
fineness and spinnability is better than the two.
 The chemical composition of banana fiber is cellulose, hemicellulose and lignin.
 It is highly strong fiber.
 It has smaller elongation.
 It has somewhat shiny appearance depending upon the extraction & spinning process.
 It is light weight.
 It has strong moisture absorption quality. It absorbs as well as releases moisture very
fast.
 It is bio-degradable and has no negative effect on environment and thus can be
categorized as eco-friendly fiber.
 Its average fineness is 2400Nm.
 It can be spun through almost all the methods of spinning including ring spinning open
end spinning, bast fiber spinning, and semi-worsted spinning among others.
 Banana fabric is soft and supple though not quite as soft as cotton or rayon. Nearly all
plant stem-based fibres are a little more stiff and coarse than cotton or rayon. Its natural
shimmer makes it look a lot like silk.
Chemical Treatment of banana:
The fibers were then treated with 5% of NaOH for one hour to increase the wet ability. The
fibers are then washed thoroughly with distilled water. Fibers are then dried in oven for 2 hours
at 100°C to remove the moisture present in it. The Banana fibers are used as reinforcement in
both epoxy and vinyl ester resin and coconut shell power is mixed with banana fiber to be used
as reinforcement material to form hybrid composite.
Figure: Alkali treated of banana fiber
Physical Treatment of banana:
Tensile Test: The testing is done using electronic tensile testing machine to measure the force
required to break a polymer composite specimen and the extent to which the specimen stretches
or elongates to that breaking point and cross head speed of 2mm/min and a gauge length of 115
mm.
Flexural Test: Flexural strength is defined as a materials ability to resist deformation under
load. It is a 3-point bend test, which generally promotes failure by inter-laminar shear.The
maximum fiber stress at failure on the tension side of a flexural specimen is considered the
flexural strength of the material.
Fine structure and appearance: commercial banana and jute fibers are in the form of strands
containing many individual fibers held together by natural gums. Both have good natural luster.
Their color depends up on the condition under which they have been processed; good quality
banana/jute is off-white, where as some poor quality fiber is nearly yellowish.
Length: The strand length varies greatly depending on the precise source and treatment of the
fiber during fiber extraction. If the fiber is removed from the full length of the sheaths, as in hand
or machine stripping fiber strands from the middle sheaths may run as long as 15ft or more;
average length ranges from 3 to 15 ft.
Tenacity modulus and elasticity: When we see the load elongation or stress strain property,
banana fiber has less tenacity and elasticity property than jute fiber.
Properties of Banana Fibers:
Tenacity
29.98 g/denier
Fineness
17.15
Moisture Regain
13.00%
Elongation
6.54
Alco-ben Extractives
1.70%
Total Cellulose
81.80%
Alpha Cellulose
61.50%
Residual Gum
41.90%
Lignin
15.00%
Banana Fiber Extraction Processing, Yarn Spinning & Weaving:
The extraction of the natural fiber from the plant required certain care to avoid damage. In the
present experiments initially the banana plant sections were cut from the main stem of the plant
and then rolled lightly to remove the excess moisture. Impurities in the rolled fibers such as
pigments, broken fibers, coating of cellulose etc. were removed manually by means of comb and
then the fibers were cleaned and dried. This mechanical and manual extraction of banana fibers
was tedious time consuming and caused damage to the fiber. Consequently, this type of
technique cannot be recommended for industrial application. A special machine was designed
and developed for the extraction of banana fibers in a mechanically automated manner. It
consisted mainly of two horizontal beams whereby a carriage with an attached and specially
designed comb could move back and forth. The fiber extraction using this technique could be
performed simply by placing a cleaned part of the banana stem on the fixed platform of the
machine and clamped at the ends by jaws. This eliminated relative movement of the stem and
avoided premature breakage of the fibers. This was followed by cleaning and drying of the fibers
in a chamber at 2000 𝐶 for three hours. These fibers were then labeled and ready for lamination
process.
Fig: Extraction of Banana Fiber from bark of Banana plant.
After fiber is collected, the process goes to yarn spinning. The researcher investigated the
traditional process, which use the filament yarns in weaving banana fabric. The finding showed
that the convention process was very time-consuming, thus not appropriate for today’s use.
Therefore, this research explored open-ended spinning process for yarn development. The fiber
was cut in to 3-centimeter length for spinning process.
After yarn spinning, weaving is done in the looms as per normal process like any other material:
Figure: Spun yarn, weaving and Banana fabric
Applications of Banana Fiber:
1. The banana fiber is extensively used as a blending material in textile industry.
2. Banana fiber is used in Pulp industry.
3. A wide range of Handicrafts are made in Banana fiber.
Uses of Banana fibers:
In the recent past, banana fiber had a very limited application and was primarily used for making
items like ropes, mats, and some other composite materials. With the increasing environmental
awareness and growing importance of eco-friendly fabrics, banana fiber has also been
recognized for all its good qualities and now its application is increasing in other fields too such
as apparel garments and home furnishings. However, in Japan, it is being used for making
traditional dresses like kimono, and kamishimo since the Edo period (1600-1868). Due to its
being lightweight and comfortable to wear, it is still preferred by people there as summer wear.
Banana fiber is also used to make fine cushion covers, Neckties, bags, table cloths, curtains etc.
Rugs made from banana silk yarn fibers are also very popular all over the world.
Fig: Uses of Banana fibers.
Problem:
Plastics and paper are the binding forces that help our information age to proceed further and
conquer new frontiers. However, both these essential goods are sourced from non-renewable
sources such as petroleum and forest trees. There is an urgent need to find alternatives to plastic
polymers since they are non-biodegradable as well which persist in the environment for ages.
Paper consumption was expected to go down steadily with the onset of the electronic age, but it
is nowhere near reduction. Further, the conventional method of making paper is highly polluting,
which uses numerous chemicals for treating the wood fibers to form pulp, and in the process of
getting papers of acceptable properties.
CONCLUSION:
In this work, Mechanical properties of untreated alkali treated banana fiber epoxy, untreated
alkali treated banana fiber vinyl ester and treated banana or coconut shell powder epoxy treated
banana or coconut shell powder vinyl ester hybrid composites were investigated. It has been
observed from the literatures were compared the resulting mechanical properties. The tensile
flexural and impact properties of the composites as a function of fiber content were analyzed.
The surface modification by alkali treatment has improved the Mechanical properties than
untreated fiber composites. The alkali treatment of banana fiber has improved the mechanical
properties like tensile flexural and impact strength of both the epoxy vinyl ester and hybrid
composite. Therefore it is conclusive from the above result that the alkali treatment has provided
better mechanical properties.
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