Establishing regularities of wood protection against water absorption using a polymer shell

This paper has analyzed protective materials for timber building structures and established the need to devise reliable methods for studying the process of water absorption by the surface of the construction structure necessary for designing new types of fire-retardant materials. Therefore, it becomes necessary to determine the conditions for the formation of a barrier for water absorption and to elucidate a mechanism for inhibiting the transfer of moisture to the material. In this regard, a mathematical model of the intensity of water mass transfer when using a polymer shell made of organic material as a coating has been built, which makes it possible to assess the effectiveness of the polymer shell by the amount of water absorbed. Based on the experimental data and theoretical dependences, the intensity of absorption of water by wood was calculated; and it has been established that the protective coating reduces the amount of water absorbed by more than 20 times. The results of determining the weight gain by a sample during water exposure indicate an ambiguous impact of the nature of protection on water absorption. In particular, this implies the presence of data sufficient for the qualitative process of inhibition of moisture diffusion; and detecting, on its basis, the point in time when the drop in the coating's efficiency begins. Analysis of the results of experiments reveals that the maximum increase in mass in the case of water absorption by a non-treated sample of wood was 40 % while the increase in the mass of wood samples treated with mixtures of oil and paraffin was less than 28 %. At the same time, the best protection is shown by a mixture of oil with paraffin within 90÷95 %. Thus, there are grounds to assert the possibility of directed regulation of wood protection processes through the use of polymer coatings that can form a protective layer on the surface of the material, which inhibits the rate of absorption of water