Abstract:
This research work comprises of experimental determination and theoretical
prediction of the effect of reinforcing fibre volume fraction and the mean reinforcing
fibre length on the mechanical properties of short jute fibre reinforced polypropylene
composite. Jute fibre reinforced polypropylene composites were prepared with
extrusion compounding and injection moulding techniques. Moisture removal or
drying was done at different stage of composite fabrication. In the present research,
Mechanical behaviour (fracture resistance, tensile properties, critical reinforcing
fibre length and the mean interfacial shear strength) of short-jute-fibre reinforced
polypropylene composites was studied as a function of fibre volume fraction and
fibre length. The values of the tensile strength, tensile modulus, failure strain and
notched charpy impact energy were obtained from each group of ten specimens. To
predict the tensile behaviour of short jute fibre reinforced polypropylene, the effect
of the variation of reinforcing fibre length and volume fraction on the tensile
strength, young's modulus and failure strain was investigated. Tensile tests were
conducted following ASTM Standard and each test was preformed until tensile
failure occurred except IOO%.polypropylene. The addition of jute fibres effectively
enhances the ultimate tensile strength and modulus. The tensile strength of the
composites increases with the increase of fibre loading up to the fibre volume
fraction 25%, beyond which tensile strength decreased or no significant
improvements were observed. A maximum of II% increase in strength and 163%
increase of tensile modulus was observed. The highest tensile strength (33.733 MPa)
is obtained from 25% jute fibre loaded polypropylene composite and the reinforcing
fibre length is 2 mm. Tensile strength showed an increasing tendency with longer
reinforcing fibre length. Fracture resistance being given by the specific work of
fracture (WOF) or fracture toughness, here viz the Notched Charpy Impact Energy of
the composites were investigated with a charpy impact tester on specimens with V-notches
according to ASTM Standard. Introduction of reinforcement effectively
enhance the impact strength of the composite but increasing reinforcement is
insignificant. Matrix material and single fibre properties were investigated. Tensile
modulus showed a decreasing tendency with the increasing reinforcing fibre length.
