Influence of organic-modified iron-montmorillonite on smoke-suppression properties and combustion behavior of intumescent flame-retardant epoxy composites

In this article, the influence of organic-modified montmorillonite (Fe-OMT) on smoke-suppression properties and combustion behavior of flame-retardant epoxy (FREP) was investigated intensively. A series of intumescent FREPs (IFREPs) with different content of Fe-OMT were prepared based on EP resin as matrix resin, ammonium polyphosphate and pentaerythrite as intumescent flame retardants, and Fe-OMT as smoke suppressant and flame-retardant synergism. Then, the smoke-suppression properties of Fe-OMT on IFREP composites were evaluated using cone calorimeter test, smoke density test, and scanning electron microscopy analysis. The influence of Fe-OMT on thermal degradation of IFREP composites were studied by thermogravimetric analysis-infrared spectrometry in a flowing nitrogen atmosphere. The pyrolysis kinetics of the composites was investigated using Kissinger and Flynn-Wall-Ozawa methods. The results showed that the heat release rate and smoke production rate of flame-retardant samples decrease greatly with the increasing Fe-OMT content. Fe-OMT can enhance char residues of flame-retardant samples and decrease the smoke production rate.