Isolation and Characterization of cellulose from Amaranthus viridis root hair waste and development of pineapple fiber vinylester composites

This study aimed to investigate the mechanical, fatigue, dynamic mechanical and creep properties of vinyl based composites reinforced using Amaranthus viridis root hair cellulose and pineapple fibe. The cellulose was produced via thermo-chemical route and the composites were manufactured using pineapple fibe mat. The composites were prepared via hand layup method and tested using ASTM standards. Results revealed that among various composite designations, the composite contains fibe and 2 vol% of cellulose showcasing a tensile strength of 175 MPa, flexural strength of 205 MPa, compression strength of 188 MPa, interlaminar shear strength of 24.7 MPa and Izod impact strength of 6.03 J. Moreover, the composite demonstrated exceptional fatigue resistance, with fatigue life counts of 39,749, 34,411 and 28,260 cycles for 25%, 50%, and 75% of ultimate tensile strength. Nevertheless, an increase in the volume percentage of cellulose up to 4 vol% resulted in a decline in both mechanical and fatigue life counts. However the dynamic mechanical analysis of composite contains 4 vol% of cellulose revealed an improved storage modulus of 5.61 GPa with a loss factor of 0.37. Additionally, the composite demonstrated diminished creep strain values of 0.0007, 0.0022, and 0.0057 for time durations of 5000 s, 10000 s, and 15000 s, respectively. Finally, the scanning electron microscopy images revealed highly reached phases of cellulose within the matrix and effective reinforcement effect. Thus it is clear that the addition of cellulose along with natural fibe improved the load bearing properties and overall structural integrity.