EFFECTS OF EXPANDABLE GRAPHITE ON FLAMMABILITY, THERMAL AND MECHANICAL PERFORMANCE OF PALM EMPTY FRUIT BUNCH FIBRE REINFORCED COMPOSITE

Abstract

Natural fibre reinforced composites (NFRC) possess the tendency of being highly flammable in nature. The current paper investigates the effectiveness of expandable graphite (EG) on the enhancement of the flame retardancy of palm empty fruit bunch (EFB) fibre filled diglycidyl ether of bisphenol A (DGEBA) thermoset epoxy composites. The EFB was treated with 5 wt% sodium hydroxide (NaOH) to improve fibre surface adhesion with the epoxy matrix. In this research, two approaches were employed to introduce EG with concentration ranging from 1 to 5 wt% into the epoxy composite filled with 20 wtn% of EFB. The first approach involved infusion of a pre-mixed EG filled epoxy resin into EFB mat during composite fabrication while the second approach considered was the application of EG filled epoxy resin as a surface coating onto post cured EFB epoxy composite. The flammability, thermal and mechanical properties were studied through a series of experiments, such as the Bunsen burner test, dynamic mechanical analysis (DMA), tensile, flexural and impact tests. The results showed that increasing EG concentration capable of enhancing the flame retardancy and mechanical behaviour in both approaches, with 5 wt% EG demonstrated superior performance in fire resistant and mechanical properties amongst other formulations.

Keywords

• Empty fruit bunch
• Epoxy
• Expandable graphite
• Flame retardant
• Palm fibre