Investigation of the Impact of Epoxy-based Composites Reinforced with Betel Nut and Coir Fiber on Physio-Mechanical Properties

Natural fibers are increasingly being used in composite production due to the detrimental effects of synthetic fibers on the environment and public health. Compared to synthetic fibers, natural fibers are more easily manufactured, less expensive, and contribute significantly to the mechanical properties of composites. This study investigates the impact of natural fibers on the mechanical and physical properties of fabricated composites. The epoxy-based composite in this work was reinforced with betel nut and coir fiber, using a hand lay-up technique as the fabrication method. During the composite fabrication, resin and hardener were used at a constant weight ratio of 80%. The length of the coir fiber ranging between 15 mm to 50 mm, and the weight percentage (wt.%) of coir fiber and betel nut fiber in the composite, ranging from 5% to 15%, were used as control factors. After testing and analyzing nine different samples, it was observed that impact strength (9.5 J/cm2), and tensile strength (4.4 MPa) were higher for 15% of coir fiber and 5% of betel nut fiber, regardless of coir fiber length. Irrespective of coir fiber length, flexural strength and hardness increased as the betel nut fiber content rose from 5% to 15%. The highest flexural strength of 1.0 MPa and hardness of 68 RHN (Rockwell hardness number) were recorded for sample 4. During the water absorption test, sample 1 with a coir fiber length of 50 mm, 5% of coir fiber and 15% of betel nut fiber showed significant performance with a 0.07% water absorption rate. These natural fiber-based composites can be utilized in the fabrication of different types of mats, bags, and clothing items. Keywords: reinforced composite; natural fiber; mechanical properties; polymer matrix; water absorption rate; hand lay-up