Examine the hardness of kenaf fiber/coir pith-based hybrid composites against coir pith-based composites

This investigation aimed to assess the impact of kenaf fiber on the hardness properties of natural composites derived from coir pith, with a focus on their potential as sustainable components in the automotive industry. The control group consisted of 15 wt% of coir pith powder, while the experimental group included 15 wt% of coir pith powder along with the specified number of layers of kenaf fiber mat. The study sought to understand the implications for the hardness properties of the natural hybrid composite, especially in relation to the increase in kenaf layers. Sample size calculations, facilitated by Clincalc.com, utilized parameters of 80% power, a 0.05 significance level, and a 95% confidence level. Each group received 20 samples, resulting in a total sample size of 40. Noteworthy disparities in hardness were observed between the experimental and control groups. The control group exhibited a hardness of 42 shore D, whereas the experimental group, particularly the 3 layers of kenaf fiber-based hybrid group, showcased a significantly higher hardness of 53 shore D. Statistical analysis with a p-value less than 0.05 validated the significance of these findings. In a practical context, the suggested surface treatment of coir pith in an alkaline environment is put forth with the specific aim of augmenting hardness in coir pith reinforced kenaf/epoxy composites. This proposed improvement opens avenues for the enhanced utilization of these composites in various applications within the materials industry, where hardness is a key factor, such as in durable structural components and wear-resistant surfaces.