Synthesis and properties of SrSn(OH)6 nanorods and their flame retardancy and smoke suppression effects on epoxy resin

A nanorod-structured strontium hydroxystannate [SrSn(OH) 6 ] flame retardant was synthesized via a facile coprecipitation method and employed in epoxy resin (EP). Based on X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy, the as-synthesized SrSn(OH) 6 nanorods exhibited high crystallinity and uniform size distribution. The flame retardancy and smoke suppression properties of EP/SrSn(OH) 6 composites were investigated by limiting oxygen index and cone calorimetry tests. The results showed that incorporation of SrSn(OH) 6 led to a dramatic reduction of the fire hazards of EP, including a 21.9% maximum decrease in the peak heat release rate, a 33.3% reduction in the toxic CO yield, and a 133.3% increase in the char residue. In particular, this is the first attempt to evaluate the flame retardancy properties of SrSn(OH) 6 nanorods in EP. The improved flame retardancy properties of the SrSn(OH) 6 nanorods is attributed to their catalytic carbonization effect.