Intrinsic cellulosic fiber architecture and their effect on the mechanical properties of hybrid composites

This study is mainly focused on the intrinsic fiber parameters and their influence on the mechanical properties of the hybrid composites. Cellulosic fibers are extracted from mesocarp ofCocos nuciferafruit and outer mat ofLuffa cylindricafruit. The inherent fiber parameters such as fiber diameter, lumen diameter, cell wall thickness are observed under light microscope. Micro-fibrillar angle is found using X-ray diffraction technique. Three varieties of hybrid polymer composite samples are fabricated usingCocos nuciferaandLuffa cylindricafibers as reinforcements in the ratio 2:1, 1:1 and 1:2 respectively employing hand layup technique with their combined weight maintained as 30%. Significant response in the Load Vs Deflection curve and mechanical properties of the hybrid composites are found attributing to the difference in the respective weight proportion of the constituent fibers in the hybrid composite system. Results exemplify that the hybrid composite sample comprisingCocos nuciferaandLuffa cylindricafibers in the ratio 1:2 capitulates the maximum flexural strength and impact strength of 31.05 MPa and 14.24 kJ/m(2)respectively when compared with other hybrid composites. The reason for the difference in mechanical strength of hybrid composite samples containing two different fibers is found to be related to the built-in architecture and physical characteristics of the constituent fibers. The morphology of the fractured samples are examined and reported. It is concluded that properties of hybrid composites can be tailor made depending upon the requirements either by using theCocos nuciferafibers to impart ductility orLuffa cylindricafibers to impart brittleness. [GRAPHICS] .