Resumen
Description of performance of fire-protective coatings during operation of a wooden construction structure is a separate and complex task that covers both stages of the protection process: both moisture protection and further heat transfer that occurs when the coating swells. It has been proven that they imply creating a layer at the surface of the material, which prevents the penetration of moisture to wood when the swelling of a wooden structure and the destruction of the coating begins. Due to this, it becomes possible to determine the effect of flame retardants and the properties of protective formulations on the process of decelerating the rate of moisture absorption of wood. When using fire-retardant coatings for wood, as it is indicated by the research results, typical processes imply the formation of a protective layer under the impact of temperature and a decrease in humidity, which slow down the moisture diffusion processes. It seems likely that such a mechanism of a fire-retardant coating is a factor in regulating the degree of formation of a weather-resistant protective layer and the effectiveness of heat and moisture insulation of the material. We have modeled the process of moisture transfer by a fire-retardant coating; the diffusion coefficient was determined and the estimation dependences were derived, which made it possible to obtain a change in the dynamics of moisture when drying a fire-retardant coating. Based on the derived dependences, the moisture diffusion coefficient of a fire-retardant coating was calculated, which amounts to 0.163·10-9 m2/s. The results from determining the mass loss of the coating sample during drying indicate the ambiguous effect of the nature of a protective agent on the change in humidity. In particular, this implies the availability of data sufficient for the qualitative implementation of the process of inhibition of moisture diffusion and the identification, on its basis, of the point in time that gives rise to a drop in the coating efficiency. The features of inhibiting the process of moisture transfer to wood, which was treated with a fire-retardant coating, include several aspects. Specifically, the use of water-insoluble flame retardants and other components, as well as a polymer binder, characterized by the formation of a heat-insulated layer at the wood surface