Thermomechanical behaviour of intumescent fire retardant coatings

Intumescent fire retardant coatings (IFRC) provide the fire protection for flammable substrates by forming a thick fire-resistance char barrier under heat exposure. This thermal insulation prevents the substrate from ignition or deformation. A lot of work has been done to describe the physical, chemical and mechanical mechanisms of the intumescent processes. Nevertheless, development of powerful IFRC is still effected by the principle "trial and error", which is labour, time and cost intensive. In this work, several components contained in the intumescent coatings were analysed single, in combination and within the coating by thermogravimetric analysis (TGA) coupled with evolved-gas analysis (EGA). Additionally, thermomechanical analysis (TMA) and visual analysis by DSC-microscopy were done. The focus is to describe the thermomechanical behaviour of the foaming process depending on selection of intumescent additives. The results are compared and discussed. The aim is to make predictions about new chemicals without using time and cost intensive fire tests.