Water absorption is one of the major concerns in using natural fibre composites in many applications. The
water absorption in hybrid composites in 24 hours, maximum and minimum water uptake was shown in the fig. 6.
Water absorption after 10 hrs increases at the rate of 1% - 5.5%.
5.2. Impact strength
The variation of impact strength with the fibre content, in case of ground nut fiber composite is presented in
figure 7. In this case, the ground nut fiber-luffa composites exhibited better impact properties. The impact strength
increases with increasing volume fraction of fibres, reaching a maximum value at 30%. Beyond 30%, the impact
strength shows a decreasing trend. The maximum impact strength of the composites varies between 0.6 Joules to
1.3 Joules. Alkali treated luffa fibers and groundnut shells showed improved impact strength. This result was in line
with the findings of Varada Rajulu et al [15] and Ramachandra reddy et al [16]. They have carried out the research
on characterization of bamboo composites.