Study the Effect of Chemical and Enzymatic Extraction Methods on the Kenaf Fibers Properties

In this paper, two extraction methods for kenaf fiber, The chemical process and the enzymatic one, were performed. These processes were used to extract fibers from the kenaf stem and the chemical, mechanical and morphologic properties of the extracted fibers were investigated. We notice that the fiber diameter decrease when increasing the concentration of the enzyme and the time treatment (101,35 mu m for Enz1 and 91,37 mu m for Enz4) the same result is obtained for the chemical extraction when increasing the duration, temperature or NaOH concentration. Also the fiber crystallinity index is improved due to the elimination of the noncellulosic materials from the fiber. The results obtained show that we have an increase in this index for all treated fiber however it is more important for the chemical extraction (crude fiber 57.39%, chemical-treated fiber 71.93% and 66.70% for the enzyme-treated fiber). This increase explains also the increase of fiber tenacity and the decrease of strain and we found through the tensile test that kenaf fiber has a pure elastic behavior for all treated fiber. So, the properties of extracted fibers compared to the crude fibers prove that the enzymatic extraction preserves more the fiber structure than the chemical extraction.