Flame retardant sisal rope: Combustion properties and characterization

Abstract

Abstract A new mechano-chemical formulation has been developed for making flame resistant sisal fibre rope with lower amount of chemical loading. Sisal yarn was treated with different formulation of ammonium sulfamate (AS) (50 and 100g/L) and the detail fire retardant property has been measured. Treatment has been carried out by dipping process at room temperature by maintaining the material to liquor ratio of 1:20. Treated sisal yarn has provided LOI value 28–32 and self-extinguishment after vertical flammability test. Forced combustion results revealed that AS treated sisal yarn has exhibited 50% less heat release rate as compared to the control sisal yarn. Sisal yarn based rope was prepared by following braiding technique, using different combinations (made by 3 yarns) of untreated and treated sisal yarn. Fire retardant sheath yarn has been used to cover the untreated sisal yarn in the core by twisting or braiding. Detail flame retardant properties of the developed ropes were measured and it exhibited LOI value range in between 30–40. Besides, a new method of simultaneous dyeing and flame retardant finishing of sisal rope also has been proposed. Physical properties of the ropes also have been measured and it was found that the extent of strength loss is negligible. Thermal stability of the AS treated sisal yarn has been measured by thermo-gravimetry analysis. Charring behaviour, another important phenomenon of the final product was examined in detail by using microscopic images and by using Scanning electron microscopy (SEM). Finally, detail mechanism lies behind the flame retardancy also has been revealed in the context with the help of XRD, FTIR analysis techniques.