Thermogravimetric evaluation of polyester/sisal flame retarded composite

An unsaturated polyester/sisal composite was formulated to achieve UL 94 V-0 performance using decabromine diphenyl oxide associated with antimony trioxide as additives. Flame retarded (FR) samples exhibited a self-extinguishment time less than 1 s. The model-free kinetic approach was applied to data for thermal oxidative decomposition of normal and FR composite samples. The activation energy (E) was calculated as function of α (conversion) and T (temperature), by using the Vyazovkin model-free kinetic method, allowing us to estimate conversion time for different temperature values. Important differences were observed in the shape of the activation energy curves for normal and FR polyester/sisal composites.