Alfa fiber/polypropylene composites: Influence of fiber extraction method and chemical treatments.

Abstract

Alfa fiber/polypropylene composites were manufactured using twin-screw extrusion. Fibers were extracted following alkaline and steam explosion methods. Three chemical treatments were also applied to alkaline extracted fibers namely, stearic acid (SA), potassium permanganate that was dissolved in water (KW) and in acetone (KA). Finally, a thermal annealing was applied to composites. It has been shown that composites with steam-exploded fibers had significantly higher melt flow index than composites with alkaline extracted fibers. Moreover, the incorporation of fibers into the matrix increased Young’s modulus where the optimum result was obtained with alkaline extracted fibers. Besides, both extraction methods significantly decreased the water uptake especially the steam explosion. The three chemical treatments increased the melt flow index and conversely decreased the tensile strength and Young’s modulus. In addition, KW treatment decreased the water uptake. Finally, the thermal annealing increased the tensile strength and Young’s modulus of composites with SA- treated fibers.