Mechanical Characterization and Water Ageing Behavior Studies of Grewia Serrulata Bast Fiber Reinforced Thermoset Composites

Natural fiber-reinforced polyester composites were prepared using bast fibers as the reinforcement which were extracted from Grewia serrulata trees. Chemical treatments such as alkali pretreatment followed by permanganate treatment, acetylation and silane treatment were exclusively applied to modify the fiber surface. Hand lay-up technique with compression molding was adapted for the fabrication of axially oriented fiber reinforced composites. Tensile, flexural and impact strength properties of the specimens prepared were evaluated following the standard procedures. The SEM images of the fractured surfaces shows improvement in compatibility between the chemically treated fibers and the matrix. It was found that the tensile and flexural strengths of chemically treated fiber-reinforced polyester composites have significantly improved when compared to untreated fiber-reinforced polyester specimens. The properties of 1200 hrs water aged specimens were found deteriorated considerably due to diffusion of water into the composite material system. The chemical treatment of fibers prior to fabrication of composites improves the resistance to water absorption tendencies.