Effect of flame retardant on the physical and mechanical properties of natural rubber and sugarcane bagasse composites

Sugarcane bagasse (SB) is waste from sugar industry. Many millions of tons of sugarcane bagasse are residues annually throughout Thailand each year. This research aimed to utilize SB mixed with the rubber compound to enhance the mechanical properties and improve flame-retardant properties. In addition, magnesium hydroxide (MH) and aluminum hydroxide (ATH) were added to study the effect of flammability of NR composites. From the results, we found that SB improved the mechanical properties and flame-retardant property, while the addition of both ATH and MH increased the efficiency of flame retardant. The cure time and scorch time of unfilled NR composites were found to be higher than that of NR filling with SB, ATH, and MH. The Mooney viscosities increased with the increase of SB, ATH, and MH. The tensile strength increased with addition of SB in composites, and when increased the content of ATH and MH tended to decrease the tensile strength of composites. The elongation at break decreased with increase in the contents of SB, ATH, and MH in composites. The microhardness, modulus at 100% and 300%, increased with the increase in SB and flame retardant. Moreover, the increase in microhardness was related to the modulus. From the horizontal burning rate analysis, it was observed that the NR composites with SB gave lower values of horizontal burning rate than the NR composites under same testing conditions. The addition of both ATH and MH enhanced to reduce the burning rate of NR composites.