Eco-Friendly Sodium Bicarbonate Treatment and Its Effect on Epoxy/Polyester Coir Fibre Composites

Abstract

This work evaluates a new eco-friendly coir fibre surface treatment method based on sodium bicarbonate (NaHCO3) solution. The fibres were treated with 10 wt.% NaHCO3 solution at different periods (24, 96 and 168 h). A full factorial design 2 1 4 1 was established to investigate the effect of the type of matrix (epoxy and polyester) and treatment time (24, 96 and 168 h) on the mechanical properties of coir fibre composites. Single fibre tensile test revealed a gradual increase in elastic modulus attributed to the treatment time factor. Epoxy and polyester composites led to higher strength and stiffness, respectively, in both tensile and flexural tests. The alkaline treatment did not affect the mechanical strength of the composites. Enhanced tensile and flexural moduli were obtained when the treatment time increased at 96 or 168 hours levels. Finally, the proposed treatment proved to be feasible and efficient in increasing the stiffness of coir fibre composites, besides being less damaging to the environment after disposal.