Flammability properties of flame retarded natural fibre reinforced polymer composites: an overview

Natural fibre reinforced polymer composites are fast replacing the synthetic ones in some areas of the composite world. Light weights, non-susceptibility to corrosion, and ecofriendly benefits of natural fibre composites are some of its attractions. Natural fibres consist of three constituents namely; cellulose, lignin and hemicelluloses with the cellulose in major and are extremely responsive to flammability of natural fibers. For this reason, their applications have been limited to regions where fire is not of great threat. The incorporation of flame retardants (FR) during the fabrication of natural fibre composites can reduced their flammability potentials and enhance thermal stability. In this study, an overview of the types of flame retardants, standard fire performance tests, cone calorimeter flammability parameters and flammability of selected natural fibers was carefully done. The global trend in halogen free flame retardant selection was emphasized and it is clearly noted that fiber surface treatment and synergetic effect of metal hydroxides FR, and/or phosphorus and nitrogen based FR with Biobased FR may be the most effective.