Water Chestnut (Eleocharis dulcis) Microfiber Reinforced Composite with NaOH Modification

Abstract

This study aimed to obtain the physical and mechanical properties of a composite made from water chestnut microfiber and e-glass with a polyester matrix. Using water chestnut (Eleocharis dulcis) as reinforcement for composite materials is a good way to utilize local materials and increase the economy of local people. It would need a modified treatment to improve the mechanical properties of water chestnut fiber-reinforced composites. The water chestnut fiber was modified by treating it with 5% volume NaOH solution and continued with 5% volume H2O2 bleaching, 50% volume H2SO4 hydrolysis, and ultrasonication. Then it was washed with water and dried in the oven for 12 hours to obtain the microfiber. The size of the water chestnut microfiber obtained was about 3-9 µm. Composite was produced using the compression molding method at a pressure of 2 MPa and a temperature of 25°C. The variations in the volume fraction of the polyester composite, water chestnut microfiber, and e-glass fiber with Volume Fraction (%) were 60%:40%:0% (sample A), 60%:0%:40% (sample B), 50%:25%;25% (sample C), 60%:40%:0% (sample D) and 70%:15%:15% (sample E). The physical characterization of composites showed that the lowest composite density and water content on samples B and A were 1.22 g/cm3 and 0.59%. In contrast, the mechanical characterization of composites showed the highest MoR and MoE on samples A and C of 87.86 MPa and 10.43 Gpa, respectively. Composite made from water chestnut (Eleocharis dulcis) modified microfiber reinforcing material with 5% volume NaOH solution and e-glass with a polyester matrix at a volume fraction composition of 50%:25%:25% is recommended.