Effect of Various Fillers on Intumescent Fire Retardant Coating and Their Influence on Fire Resistance

In this study the effect of various fillers (HNTs, Zinc Borate and Nano Alumina) on intumescent fire retardant coating and their influence on fire resistance were investigated. Intumescent coating formulations were developed by using different weight percentages of the fillers in basic ingredients of coating. The performance of the formulations was investigated by furnace test, fire test, Fourier Transform infrared analysis (FTIR) and X-ray diffraction (XRD). Char expansion from furnace test proved that the highest char expansion has been achieved with the use of fillers. Fire test results showed that the fire performance has improved with the addition of HNTs, zinc borate and nano alumina. The char expansion has also expanded the highest with the addition of the fillers. XRD proved the development of mullite which is a stable compound and zinc pyrophosphate is released by zinc borate which then reacted with ammonium polyphosphate forming boron phosphate and cyanocinnoline. FTIR results showed the formation of zinc structures that are high-temperature stable and P-O-P, B-O-P and Si-CH3 bonding. By adding fillers, the properties of intumescent fire retardant coating and fire performance has been enhanced.