Bagasse fiber-polypropylene based composites

Processing and properties of bagasse fiber-polypropylene composites are reported. Four different chemical treatments of the vegetal fibers were performed in order to improve interface adhesion with the thermoplastic matrix: namely isocyanate, acrylic acid, mercerization, and washing with alkaline solution were applied. The effects of the treatment reactions on the chemical structure of the fibers were analyzed by infrared spectroscopy. Optical photomicrographs indicate that a highly fibrillated surface is achieved when fibers are mercerized. The effects of the fiber chemical treatment on the tensile properties of the molded composite, produced by different processing routes, were also analyzed. It was observed that the tensile strength and the elongation at break of the polypropylene matrix composite decrease with the incorporation of bagasse fibers without treatment. However, isocyanate and mercerization treatments enhance the tensile properties of the composite. Moreover, creep measurements were also carried out on the various composites studied. The best results were obtained on materials with treated fibers. The highest creep activation energy was obtained on the composite with the mercerized fiber.