Influence of Iron Oxide Brown on Smoke-Suppression Properties and Combustion Behavior of Intumescent Flame-Retardant Epoxy Composites

This article mainly deals with smoke-suppression properties and synergistic flame-retardant effects of iron oxide brown (( Fe2O3 + FeO) center dot nH(2)O) on intumescent flame-retardant epoxy resins ( IFREP) using ammonium polyphosphate and pentaerythritol as intumescent flame retardants. The smoke-suppression properties and flame retardancy of iron oxide brown on IFREP compositions were investigated by the cone calorimeter test ( CCT), scanning electron microscopy ( SEM), and thermogravimetric analysis-infrared spectrometry. Remarkably, CCT data revealed that the incorporation of iron oxide brown into IFREP compositions can significantly reduce heat release rate, total heat release, smoke production rate, and total smoke release, and so on. On the other hand, the SEM results showed that iron oxide brown can greatly improve the structure of char residue. The thermogravimetric data indicated that iron oxide brown had different effects on the process of thermal degradation of the IFREP compositions. The volatilized products formed on thermal degradation of IFREP compositions indicated that the volatilized products were H2O, CO2, CO, carboxylic acid, and aliphatic hydrocarbons according to the temperature of onset formation. Here, iron oxide brown is considered to be an effective smoke-suppression agent and a good synergism with IFR in flame-retardant epoxy resins, which can greatly enhance the char residue. (c) 2015 Wiley Periodicals,Inc. Adv Polym Technol 2015, 34, 21516; View this article online at wileyonlinelibrary. com. DOI 10.1002/ adv. 21516