Influence of ferrite yellow on combustion and smoke suppression properties in intumescent flame-retardant epoxy composites

A series of intumescent flame-retardant epoxy resins (IFREP) were prepared based on bisphenol A epoxy resin (EP) as matrix resin, ammonium polyphosphate (APP) and pentaerythritol as intumescent flame retardants (IFRs), and ferrite yellow (goethite) as smoke suppressant. Then, the synergistic flame-retardant and smoke suppression properties of -FeOOH on IFR epoxy composites were intensively investigated using cone calorimeter test and scanning electron microscopy. The thermal degradation process of IFR epoxy composites were studied using thermogravimetric analysis-infrared spectrometry under nitrogen atmosphere. Then, the pyrolysis kinetics parameters were investigated using Kissinger and Flynn-Wall-Ozawa methods. The results showed that goethite can significantly reduce heat release rate, total heat release, smoke production rate, and total smoke release. There are obvious synergistic flame-retardant and smoke suppression effects between goethite and IFRs in epoxy composites.