NANOCOMPOSITES - A REVOLUTIONARY NEW FLAME-RETARDANT APPROACH

To evaluate the feasibility of controlling polymer flammability via a nanocomposite approach, we have examined the flammability properties o f nylon-6 clay-nanocomposites, The fire retardant (FR) properties of t his new class of materials, organic-inorganic nanocomposites, are repo rted. The cone calorimeter data show that the peak heat release rate ( HRR), the most important parameter for predicting fire hazard, is redu ced by 63 percent in a nylon-6 clay-nanocomposite containing a clay ma ss fraction of only five percent. Not only is this a very efficient FR system, hut, it does not have the usual drawbacks associated with oth er FR additives, That is, the physical properties are not degraded by the additive (clay), instead they are greatly improved. Furthermore, t his system does not increase the carbon monoxide or soot produced duri ng the combustion, as many commercial fire retardants do. The nanocomp osite structure appears to enhance the performance of the char through reinforcement of the char layer. indeed, transmission electron micros copy (TEM) of a section of Che combustion char from the nylon-6 clay-n anocomposite (five percent) shows a multilayered silicate structure. T his layer may act as an insulator and a mass transport barrier slowing the escape of the volatile products generated as the nylon-6 decompos es.