ABSTRACT
Wheat straw, a lignocellulosic fiber is an agricultural by-product found abundantly everywhere in Bangladesh. This fiber contains about 35% α-cellulose, 25% hemi-cellulose, 23% lignin. As compared to other natural fibers, it is a low cellulosic fiber. Acetylation and alkylation of this fiber were carried out and modified fibers were characterized by physical, mechanical and thermal methods, such as moisture absorption, tensile properties, thermal properties and surface morphology. The moisture content decreases by increasing extent of acetylation and alkylation. Moisture content of alkylated fibers is lower than that of acetylated fibers. Ultimate tensile strength of alkylated fibers are higher than that of acetylated fibers and about 120 MPa for 20% NaOH treated fiber. The Elongation at break or strain of wheat straw fiber increases by increasing extent of acetylation and alkylation. The Young’s Modulus of treated fiber increases upto the 10 wt% (concentration) for both treatments. From the analysis of DTA, DTG and TGA profiles, it is found that the thermal stability of acetylated fibers is higher than that of alkylated fibers.
