Chemical and Mechanical Properties of Diss (Ampelodesmos mauritanicus) Fibers

In the present study, natural Diss fibers (Ampelodesmos mauritanicus) were treated and characterized in terms of physico-chemical performances and mechanical properties. The Diss fibers main constituents with their weight proportions are cellulose (44.1%), hemicelluloses (27%), lignin (16.80%), extractives (9%), and ashes (3.1%). The measured specific density (0.89 g/mL) decreases about 5% when alkaline treatment was used. The average elastic modulus, tensile strength, and tensile elongation at failure are respectively 9.3 Gpa, 149 Mpa, and 1.72% for a 20 mm gauge length. The degree of variability in fiber strength results at different gauge lengths was quantified by Weibull statistics. The Weibull modulus decreases from 2.96 to 2.73 and the tensile strength scale parameter decreases from 161 to 105 Mpa as the gauge length increases from 20 to 80 mm. We also investigated the alkali treatment effects on the mechanical properties and on the fibers structure. When treated with 5% NaOH during 2h, the Diss fibers tensile strength increased tremendously by about (37%). Longer processing time did not show any appreciable improvement. However, the tensile strength remains higher than for the untreated fibers.