O. D. SAMUEL ET AL. 781
not only on the properties of the components but also on
the mechanism of composite failure which is a function
of how well the composite was formed [14].
Oladele et al. [15] reported that the fibre/matrix has an
important role in the micromechanical behaviour of
composite. Lack of good adhesion with the polymeric
matrix, and large moisture absorption of natural fibres
adversely affe ct adhesion with h ydrophobic matrix mate-
rial .These problems often lead to premature ageing by
degrading and l oss of strength.
Natural fibre-reinforced composites have been increas-
ingly utilized in quite widespread applications. Natural
fibres are obtained from different parts of the plants, to
name a few, for example jute, flax, kenaf, coconut, hemp,
ukam, sisal, banana, pineapple fibres from the leaf; cot-
ton and kapok from seed; coir and coconut from the fruit.
For example hemp, jute, flax and sisal fibres are already
used in automotive indu stry [16].
In polymeric composite terms, natural fibre reinforce-
ment is a manufactured assembly of long or short bun-
dles of natural fibres to produce a flat sheet or mat of one
or more layers of fibres. These layers are held together
either by mechanical interlocking of the fibres them-
selves or with a binder to hold these materials together
giving the assembly sufficient integrity to be handled.
The un-reinforced plastics have low density, are rela-
tively easy to process, resistant to weathering and do not
require a surface finish.
The components of natural fibres are cellulose, hemi-
cellulose, lignin, pectin, waxes and water soluble sub-
stances. The cellulose, hemicellulose and lignin are the
basic components of natural fibres, governing the physi-
cal properties of the fibres [17]. In order to fully utilize
the natural fibres, understanding their physical and me-
chanical properties is vital. A unique characteristic of
natural fibres is depended upon the variations in the
characteristics and amount of these components, as well
as difference in its cellular structure. Therefore, to use
natural fibres to its best advantages and most effectively
in automotive and industrial application, physical and
mechanical properties of natural fibres must be consid-
ered. Many studies have investigated the properties of
natural fibres. Numerous researchers have studied me-
chanical properties of varied natural fibres [18]. Tradi-
tionally, natural fibres are used and known for rope,
twine, and course sacking materials; and they are biode-
gradable and environmentally friendly crop. All men-
tioned studies have assisted engineers with the design
and efficient usage of the natural fibres. However, the
fibers modification is required and needed to improve
mechanical properties for composites product. Efficiency
of the fiber-reinforced composites also depends on the
manufacturing process that the ability to transfer stress
from the matrix to fiber [19]. In this study, natural fibre
laminated laminates were made by hand lay-up method
and their mechanical properties were investigated in or-
der to assess its suitability.
2. Material and Methods
2.1. Materials and Equipment
The composite materials used in the production of the
specimens include: E-glass fibre (artificial fibres) ukam
plant, resin, fibres, wax, release agent, gel coat and mis-
cellaneous items. The equipment used are weighing bal-
ance, cloth, stirrers, measuring cylinder, universal testing
machine.
2.2. Fibre Treatment
In this study, chemical resetting was used. The procedure
involves NaOH solution treatment, water washing and
drying. Natural fibres are extracted from their parent
plant. The ukam, sisal and banana are extracted from the
back of their stems, while hemp and coconut are ex-
tracted from their fruits. The natural fibres, after being
extracted, are washed with water to remove gums. The
fibres are then treated with sodium hydroxide solution
and rammed. The treated fibre was allowed to dry in the
sun for 3 days. After which the fibres are laid in the mold
with the resin at the ratio of 30% to 70%. It was allowed
to cure for about 20 days.
2.3. Laminate Manufacture’s Methods
In this study, samples of laminates were made by using
hand lay-up method. The method used in this study was
employed due to its simplicity and availability of the
items. Details of the procedures taken in the production
of laminates via hand lay-up method are elsewhere dis-
cussed (Agbo, 2009).
2.4. Measurement
2.4.1. Tensile Test
The tensile tests were performed using a testin g machine
model 8889. The width and the thickness of the speci-
mens were measured and recorded (360 mm by 20 mm
by 5 mm). The tensile tests were carried out according to
ASTM D 038-01. The tensile strengths were calculated
from this test.
2.4.2. Bending Test
Three point bending tests were performed using a testing
machine in accordance to ASTM D 790 standards. For
the bending test, samples with dimensions of 300 mm ×
20 mm × 5 mm were used. The bending strength test was
carried out on the tensometer with its attachment fixed
properly bending strengths were evaluated.
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