Comprehensive Characterization of Lignocellulosic Fruit Fibers Reinforced Hybrid Polyester Composites

This work is focused to fabricate and characterize hybrid polyester composites containing equal weight percentages of lignocellulosic fruit fibers namely Cocos nucifera and Luffa cylindrica. Samples with four different compositions (10%, 20%, 30%, and 40%) containing random fiber orientation are fabricated using handlayup technique and their effect on the flexural strength and impact strength is studied and compared with their individual counterparts. Enhanced mechanical properties are obtained when the combined weight percentage of both fibers is 30% by weight. This hybrid composite sample is characterized by Fourier Transform Infrared spectroscopy, X-ray diffraction and Thermogravimetric analysis. Surface morphology of the fractured sample with elemental analysis is studied using scanning electron microscope and Energy Dispersive Analysis of X-rays. FTIR peaks confirm the presence of biopolymers cellulose, hemicellulose and lignin. The thermogram confirms the presence of lignin, an amorphous hydrophobic biopolymer with strong intermolecular, intramolecular hydrogen bond and cross linking of the molecules requiring more energy to breakdown resulting in good thermal stability of the hybrid composites around 200°C. Elemental analysis gives O/C ratio of 0.45 corroborating the lignin presence at the surface.