Thermal Analysis Coupled with Microscopy for In-Situ Investigation of Intumescent Fire Protective Coatings

The research on intumescent coatings as passive fire protection of substrates has increased rapidly in recent years. Herein, improvement of existing intumescent systems and exploring new systems are closely related to the drawbacks of existing commercial intumescent coatings. These include incorporation of toxic species, exothermic decomposition, release of toxic gas, and low mechanical strength [1]. To make a breakthrough in the market of intumescent coatings, the aforementioned challenges must be solved. However, the temperature-activated working mechanism of intumescent coatings is complex to map. Currently, a large variety of technical methods exist to characterize, and ultimately understand, the thermal induced interactions. However, those are mainly based on post-mortem analyses. Hot stage microscopy (HSM), shown in Figure 1, is one of few techniques allowing in-situ characterization of dynamic changes at high temperatures, which has been a long-lasting challenge within intumescent coatings research.