Banana fibers and microfibrils as lignocellulosic reinforcements in polymer composites

Banana plant waste, as lignocellulosic fiber, was treated with alkaline pulping and steam explosion to produce banana fibers and banana microfibrils. The chemical composition of the ensuing fibers and microfibrils was determined. The chemical modification, with maleic anhydride, of the produced particles was further carried out. The FT-IR analysis and scanning electron microscopy observations of the resulting modified and unmodified banana fibers were investigated. Composite materials were processed from these natural unmodified and maleated lignocellulosic fibers using polyethylene as the polymeric matrix. The thermal and mechanical properties were studied by differential scanning calorimetry (DSC) and tensile tests, respectively. The morphology of processed composites was studied by scanning electronic microscopy (SEM). Better compatibility and enhanced mechanical properties were obtained when using banana microfibrils. The chemical composition of fibers, in terms of lignin and cellulose, as well as their degree of crystallinity, were found to have a strong influence on the mechanical properties of the composites.