Title
Influence of fiber pretreatment on the mechanical properties of Dharbai fiber reinforced polyester composites
Authors
S. KALYANA SUNDARAM S. JAYABAL and K.NIJANDHAN

Published Volume 49 Issue 1 January
Keywords Dharbai fibers, fiber surface treatment, mechanical properties, scanning electron microscope

Abstract
A new variety of Dharbai fibers (botanical name: Eragrostis cynosuroides) used as reinforcement in polyester matrix composites were subjected to surface modifications using sodium hydroxide (NaOH) aqueous solution with a view to enhancing the mechanical properties of Dharbai fiber reinforced polyester composites. The fibers were treated with aqueous sodium hydroxide solution by varying the treatment parameters, namely solution concentration and soaking time of sodium hydroxide solution, and the composites were prepared using the compression moulding process. The mechanical properties of fabricated composites were tested as per ASTM standards. The effects of solution concentration and soaking time on tensile, flexural and impact strength of the Dharbai fiber reinforced polymer composites were studied and the best fiber treatment conditions for better mechanical properties were identified. The investigations confirmed that surface modification by removal of excess cellulose, lignin and alkali soluble particles from the fiber surface improved the fiber–matrix adhesion, which in turn exhibited better mechanical properties compared to those of untreated Dharbai fiber reinforced polyester composites.