Comportamento mecânico de compósitos produzidos com reaproveitamento de polietileno de alta densidade, reforçados com fibras de sisal

Abstract

The production and consumption of materials that use plastics have been strongly studied. The use of its raw material, petroleum, and its incorrect disposal, can cause significant damage to environment. There is also a tendency of using natural fibers that can reinforce plastics to provide superior materials, forming composites. Considering a material largely used by man, the plastic bag made of high density polyethylene (HDPE), and the possibility of reusing this material, this study aims to characterize the mechanical behavior of composites made with reuse of HDPE from plastic bags, with woven sisal fibers as reinforcement. Plastic bags with HDPE from traditional type, originated from petroleum, and the green type, originated from ethanol of sugarcane, were investigated as matrix of composites. Woven sisal fibers were arranged in [0°/90°/0 °] and [± 45 °] orientations. Three - point flexural, tensile and Charpy impact tests were performed. Three-point flexural tests showed that composites reinforced with woven sisal fibers in orientation [± 45°] had higher modulus of elasticity in bending that composites reinforced with woven sisal fibers in orientation [0°/90°/0 °]. Tensile and Charpy impact tests showed that composites reinforced with woven sisal fibers in orientation [0°/90°/0 °] had higher modulus of elasticity in tensile, tensile strength and energy absorved by impact that composites reinforced with woven sisal fibers in orientation [± 45°]. Regarding to the matrix composites, results about mechanical behavior of composites with green HDPE showed that this material can be a substitute of traditional HDPE as matrix in composites.