Effect of alkali treatment on the mechanical and interfacial properties of woven jute and kenaf fiber reinforced epoxy composites

The natural fibers like jute and kenaf have been taken as sustainable reinforcement of polymer composites as they are low density, renewable and possess good specific strength. They, however, have minimal ability to bond to hydrophobic polymer matrices due to their hydrophilic character. This paper has used the woven jute and kenaf fibers as a subject to the alkali treatment by using sodium hydroxide (NaOH) solution to enhance interfacial bonding between fibers and a matrix in the epoxy-based composites. A hand lay-up procedure was used with compression molding to make composite. The mechanical properties, tensile, flexural and impact strength were checked according to the ASTM standards. The fracture surfaces were scanned using the Scanning Electron Microscopy (SEM) which was used to assess the fiber- matrix interfacial characteristics. The alkali-treated fiber composites were found to have immense enhancement on mechanical strength, as well as decreased void content, in comparison to the untreated samples. The data show that the alkali treatment is an effective method used to eliminate surface impurities, hemicellulose, and lignin, which increases the interfacial bonding and effectiveness of load transfer in woven natural fiber composites.