Natural fibers (Sisal and Coconut coir) reinforced
Epoxy composites were subjected to water immersion tests in order
to study the effects of water absorption on the mechanical
properties. Natural fibers like coconut coir (short fibers) and sisal
fibers (long fibers) were used in hybrid combination and the fiber
weight fraction of 20%, 30% and 40% were used for the
fabrication of the composite. Water absorption tests were
conducted by immersing specimens in a water bath at 250 C and
1000 C for different time durations. The tensile and flexural
properties of water immersed specimens subjected to both aging
conditions were evaluated and compared with dry composite
specimens. The percentage of moisture uptake increased as the
fiber volume fraction increased because of the high cellulose
content of the fiber. The tensile and flexural properties of Natural
fiber reinforced Epoxy composite specimens were found to
decrease with increase in percentage moisture uptake. Moisture
induced degradation of composite samples was observed at
elevated temperature. The water absorption pattern of these
composites at room temperature was found to follow Fickian
behavior, whereas the water absorption properties at higher
temperature did not follow Fick’s law.