Intumescent coatings are fire retardant coatings in which an intumescent reaction occurs at temperatures between 200 °C and 250 °C. The coating then expands to form a thick char layer that acts as a thermal insulator, protecting the surface from heat and combustible materials. Due to their aesthetics and ease of application, they are the most popular among passive fire protection products. The fire retardant properties of intumescent coatings can be improved by various additives, such as layered double hydroxides (LDH).
The objective of my diploma thesis was to synthesise zinc-aluminium LDH, which was then added to intumescent coatings to improve their fire retardant properties. The coprecipitation method was used to synthesise Zn-Al LDH at constant pH. Then, the chloride ions were replaced by carbonates through an ion exchange reaction. Both structures of LDH were confirmed by X-ray diffraction analysis (XRD). Synthesized LDH was added to two different intumescent coatings in different mass fractions. The coatings were applied to wooden cubes. Thermoanalytical methods were used to compare the differences in the behaviour of the coatings during exposure to elevated temperatures. Based on the obtained results, we tried to find the coating with optimal properties.
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