Effect of Kaolin Clay on Thermal Degradation of Intumescent Fire Retardant Coating

Abstract—In this paper we have studied the thermal behaviour of Intumescent coating. Intumescent coating is an insulating system designed to decrease heat transfer from a fire to substrate structure to maintain its integrity. The coating was based on Expandable graphite (EG), Ammonium Poly Phosphate (APP), Melamine (MEL), Boric Acid (B.A) Bisphenol A (BPA), Kaolin clay (Al2Si2O5(OH)4) and Tetra ethylene tetra amine(TETA) as curing agent. Different formulations were developed to study the heat shielding effect of coating, thermogravimetric analysis and scanning electron microscopy (SEM). The result showed that by adding the filler Kaolin, the fire retardant time of coating was extended. The largest improvement was achieved with 5 wt% of kaolin clay with 10 wt % of Boric acid.