Influence of magnesium hydroxide on thermal decomposition of intumescent fire-retardant epoxy coatings

Intumescent fire-retardant epoxy (IFR-EP) coatings including ammonium polyphosphate (APP), pentaerythritol (PER), melamine (MEL), magnesium hydroxide (MH), epoxy resin (EP) and polyamide resin (PA) were prepared. Thermal decomposition processes of the pure EP-PA, APP, PER, MEL and MH by thermogravimetric analysis (TGA) technique indicate that the decomposition temperature ranges of EP-PA, APP, PER and MEL are properly consistent with the intumescent mechanism of flame retardants. Thermal decomposition of IFR-EP coatings shows that 15 parts per hundred parts of resin MH is more appropriate to be selected in the formulation of IFR-EP coatings. Kinetic analysis of the TGA data based on the Kissinger methods revealed that activation energy could be used as an important parameter to judge the thermal decomposition process. The conversion dependencies of the activation energy plot show the complex effect of MH content on the thermal decomposition process of IFR-EP coatings.