Comparative study of the characteristics of green and brown coconut fibers for the development of green composites

Abstract

The growing consumption of tender coconut water in Brazil has resulted in a generation of green husk, which in turn has led to pollution, as it takes eight to ten years to degrade. With the objective of finding applications for these fibers, the characterization of their chemical composition, tensile properties, and structural properties is presented in this paper. The density of the green fibers was 1200 kg/m3, and the diameter ranged between 272 μm and 513 μm. The length of the ultimate fibers was 940 μm, while the cell wall thickness and size of lumen were approximately 3.6 μm and 11.8 μm, respectively. The crystallinity index, ultimate tensile strength, Young's modulus, and elongation of the lignocellulosic fiber were 48%, 114 MPa to 159 MPa, 1.20 GPa to 1.96 GPa, and 41% to 44%, respectively. These results were compared with previously published results of both green and brown coir fibers with the purpose of exploring the addition of value to this abundant agro-industrial residue.