Abstract:
The use of natural fibers as fillers in the rubber industry is a new trend. Banana fibres has been
incorporated into phenol formaldehyde and polyester resins as a reinforcing material. However,
the use of banana fiber in dry rubber formulations is novel. The main objectives were to study
the banana fibre extraction processes, to identify the most suitable process, and to examine the
usage of banana fibre as potential filler in natural rubber (NR) compounds by characterizing the
compounds chemically, mechanically and physically. In this study, banana fibres were extracted
using three methods namely water retting, chemical retting and mechanical extraction.
Extraction time, yield and tensile properties of fibres for different extraction processes were
studied to identify the best suited method. The dried ground fibres in a range of 0.01 - 1.2 mm
prepared and incorporated into a natural rubber compound at fibre loading from 0 to 50
phr at 10 phr intervals. Coupling agent, a two component system of phenol formaldehyde and
hexamethylene tetra amine was also used. Mechanical extraction was identified as the most
suitable process for fibre extraction. Banana fibres were composed of high cellulose content,
which is favorable in order to enhance its reinforcement effect in NR compounds when added
with the coupling agent. Cure time and scorch time decreased with the banana fibre loading and
further with the coupling agent. Hardness and modulus increased with the fibre loading, while
tensile properties decreased. With incorporation of the coupling agent, hardness and modulus
further increased, tensile strength, elongation at break and tear strength increased at every fibre
loading by up to 40%, 200% and 22% respectively. Banana fibre alone behaved as diluent filler,
but banana fibre with the coupling agent showed reinforcement to the rubber compound