Mechanical properties and biodegradability of enzyme-retted kenaf fiber composites

Abstract

The mechanical properties and biodegradability of retted kenaf and modified starch composites fabricated by adding enzyme-retted kenaf as a filler and poly(vinyl alcohol) (PVA), poly(ethylene glycol), or glycerol as a plasticizer are compared with those of the NaOH-retted counterparts fabricated under identical conditions. In the case of enzyme retting, the composite treated with the PVA plasticizer was deemed the most appropriate for achieving optimal tensile strength, flexural strength, and flexural modulus. Further, the retting treatment, the length of the kenaf fiber, the type of treatment (single- or double-sided), and the adhesion force at the interface significantly affect the mechanical properties of the composites. According to the aerobic biodegradability assessment in natural reclamation conditions, the modified starch composite fabricated using 50-mm-long enzyme-retted kenaf fibers as the filler and double-side treated with PVA plasticizer showed a biodegradation rate of 80% or higher after 80 days.