Fire and heat-protective materials are one of the most popular types of coatings. The versatility and efficiency of their intended purpose is one of the important components of safety in the event of fires. As part of this work, research was carried out on the production of a fire-heat-protective coating based on acrylic dispersion, which is characterized by the safety of the base due to the absence of solvents in the composition. It was found that acrylic dispersion Lacroten® brand E-55 should be used as a coating base, with an average viscosity of 100-200 mPa s, with a minimum film formation temperature of minus 5°C. Ammonium polyphosphate, melamine, pentaerythritol, dolomite, and vermiculite were used individually and in mixtures as components to increase fire and heat-protective properties. Based on thermal studies (DTA, DTG) and the fire tube method, it was found that mixtures of ammonium polyphosphate, melamine, dolomite should be used in an amount of 30% by weight. To optimize the ratio of these components, the Scheffe simplex lattice plan (model 7) was used. The assessment was carried out according to three parameters: viscosity of the mixture, coating consumption, weight loss of the wooden sample when tested using the “fire tube” method. As a result of experimental studies, it was found that in order to ensure protective properties, coatings should have the following composition: acrylic dispersion Lacroten® E-55 - 70%; ammonium polyphosphate - 24-28%; melamine - 0-6%; dolomite - 2-6%. These coatings have sufficient fire-protective (wooden samples with the applied protective layer do not burn on their own) and technological properties (application and curing is possible at temperatures above 5ºС; when applying the coating with a brush, a uniform thickness is ensured): flammability class G1, i.e. they do not support independent combustion, the loss of mass of a wooden sample with the applied coating when using the “fire tube” method is in the range of up to 20%, the degree of damage to samples with the applied coating along the length is 50-60%; viscosity of the mixed composition is 200-3200 mPa s; coating consumption to ensure heat-protective properties is 0.05-0.08 g/cm2.
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