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Based on the analysis of literature sources, the article finds that today it is difficult to imagine the protection of human lives from fire without fire-retardant coatings on textiles. Precisely defined standards allow to determine the requirements for textile materials that have fire protection. It is hardly possible to prevent the inflammation of textiles due to their physical parameters (melting point, flash point). However, it is possible to extend the time for people to escape to start rescue operations by using appropriate fire protection systems or a combination of individual active ingredients. Reducing flammability and developing flammable and combustible materials is one of the main ways to prevent fires and solve the problem of expanding the scope of these materials. Treatment with flame retardants significantly affects the spread of flames, can significantly reduce the ability to smoke and heat. Therefore, research aimed at determining the patterns of fire protection paths used for the manufacture of textiles is relevant. One of such promising areas is the study of the formation of a layer of foam cone in the fire protection of the fabric with intumescent coatings. Experimental studies to determine the fire-hazardous properties of the tectile material revealed the ignition of the untreated sample, while for the fire-retardant – the process of ignition and spread of the flame did not occur. Inhibition of the process of ignition and spread of flame for such a sample is associated with the decomposition of flame retardants under the action of temperature with heat absorption and release of non-combustible gases (nitrogen, carbon dioxide), changing the direction of decomposition towards non-combustible gases and flame retardant coke. This indicates the possibility of transition of the textile material during the processing of the composition to materials that are flammable, do not spread the flame on the surface.

Paints and varnishes are used to a large extent to protect wood surfaces in outdoor conditions, as they are easy to maintain and reapply. Also, when developing a coating, manufacturers are guided by the need to obtain a number of properties that generally determine its ability to protect against moisture. To obtain a protective coating that meets the specified requirements, it is necessary that the components that make up the coating belong directly to the group of protective materials or form such compounds under operating conditions, be able to adhere to the surface of the product. It was found that thermal modification provides a decrease in water absorption of wood. Additional processing of the wood surface helps to reduce moisture absorption by 2 times, and for samples modified at a temperature of 220 °C – 3 times. Geometric dimensional stability is also improved by a factor of 2. The effect of heat treatment on the water absorption of wood is somewhat less – for samples modified at 190 and 220 °C for more than 10 hours. Protective substances for thermally modified wood provided similar protection of open thermally modified surfaces of wood from the effects of water. The positive effect of thermal modification on a decrease in the level of water absorption has been established. It has been proven that it is temperature that has a significant effect on such changes. Since the protective coating is also susceptible to photochemical degradation, it is very important to renew it in a timely manner in accordance with the manufacturer's instructions for the pleasant appearance of wood surfaces during external use. The optimal ratio of components in the surface layer of thermally modified wood has been determined, which ensures the fulfillment of the task, namely for a mixture of oil and wax: the density of a wood – 724 kg/m3; oils – 70.0%; wax – 17.5%. Therefore, such treatment is beneficial for the protection and aesthetic appeal of wood products.

The processes of creation of fire-retardant varnish for wood consisting of a mixture of inorganic and polymeric substances are investigated in the work. It is established that the optimization of the inorganic component leads to a directional ratio of mineral acids and urea capable of effective fire protection of the material. Studies have shown that at the initial temperature of gaseous combustion products T = 68 °C, when exposed to the radiation panel, the untreated sample ignited after 146 s, the flame spread over the entire surface, instead, the sample fire-protected varnish did not ignite, the maximum temperature was 105 °C. In this case, as evidenced by the results of heat resistance, there is a change in the structure of the protective film of the coating. The thickness of the protective layer increases due to the decomposition of the composition, which leads to inhibition of oxidation in the gas and condensed phase, change the direction of decomposition towards the formation of non-combustible gases and combustible coke residue, reduce material combustion and increase flammability index. The coating under the influence of high temperature promotes the formation of a heat-insulating layer of coke, which prevents burning and the passage of high temperature to the material, which is confirmed by the absence of the process of ignition of fire-retardant wood. Features of braking of process of ignition and distribution of a flame of the wood processed by a varnish which consist in several aspects are established. This is the formation of a heat-insulating layer of coke, which prevents burning and the passage of high temperatures to the material, which is confirmed by the absence of the process of ignition of fire-retardant reeds. This indicates the possibility of targeted control of high temperature transfer processes to organic material through the use of special coatings for wood products.

t. The problem of using natural building materials in low-rise construction lies in ensuring their durability during operation in conditions of atmospheric fluctuations, as well as in ensuring their thermal insulation properties. The purpose of this study is to find the thermal insulation properties of materials, namely thermally modified common hornbeam wood (the outer surface of the building), common pine wood (the inner surface of the building) and a thermal insulation layer of reeds, which allow justifying the effectiveness of their use in construction. The study uses a comprehensive research method, which included figuring out the thermal insulation properties of materials and justifying their feasibility in construction. The thermal insulation properties of wood and reed materials were calculated based on thermophysical dependences. The coefficient of thermal conductivity for wood reaches 0.0082 W/(m∙K), and for reed – 0.0022 W/(m∙K). Therewith, the thermal conductivity is no more than 0.19·10-6 m2 /s, the heat capacity of wood is within 70÷90 kJ/(kg·K), and the heat capacity of a reed product is 337.2 kJ/(kg·K) respectively, which refers them to thermal-insulating materials. The practical value of this study lies in the substantiation of the method of establishing thermal insulation characteristics of building materials by finding their physical and thermophysical properties. The obtained results also expand the scope of application of products and building structures made of wood and reed

The problem of using fire-resistant materials for wooden building structures is to ensure their stability and durability when operating in atmospheric conditions, when it is possible to wash out flame retardants and lose fire resistance. The purpose of this study is to identify the indicators of fire hazard of wood, fire-proof coatings and the effect on them of the heat-insulating layer of coke formed, which allow justifying the effectiveness of the fire-resistant coating under the influence of temperature. The study used a comprehensive research method, which consisted in determining the fire-hazardous properties of fire-proof wood and methods for determining the operational properties of wood fire protection. It was found that upon applying a coating based on alkyd-polyurenitan varnish, due to the polymer film formed on the wood surface, the permeability of flame-retardant components decreases. Tests of fire-hazardous features of wood protection from fire have shown that the coating swells under the influence of heat flow and contributes to a significant heat-insulating layer of coke, which prevents oxygen from reaching the wood and, accordingly, hot temperature, which can ignite the wood. In general, the effectiveness of wood protection from fire shown that wood protected from fire belongs to hard-to-burn materials that slowly spread flames on a surface with low smoke-forming ability. The practical value of this paper lies in the fact that the obtained method for identifying the features of wood protection from fire, comprises determining both atmospheric and thermal properties, and allows establishing the operating conditions of fire protection and the use of products and building structures made of wood of a wide range of uses

Досліджено вплив наповнювачів на втрату маси деревини, захищеної покриттям на основі неорганічних та органічних речовин у процесі термічного впливу, особливістю якого є дослідження вогнезахисної ефективності композиції. Це завдання виконано за стандартними методиками. Встановлено вплив наповнювачів за дії високотемпературного теплового потоку на зміну процесу втрати маси вогнезахищеної деревини та визначено механізм кінетики дії наповнювачів, який характеризується зниженням швидкості та втрати маси. Зокрема, для зразка деревини з вогнезахищеним покриттям з високотемпературним наповнювачем, відбувається поступове зниження температури, тобто зафіксовано роботу покриття, а відповідно зниження димоутворювальної здатності деревини з вогнезахищеним покриттям. Із метою встановлення вогнезахисної ефективності при застосуванні високотемпературних наповнювачів покриття (із додаванням алюмосилікатних мікросфер, перліту, базальтової луски, золи, металургійного шламу) було проведено дослідження щодо визначення групи горючості деревини за показниками втрати маси та приросту температури димових газів і встановлено, що при обробленні деревина переходить до групи важкогорючих матеріалів. За результатами термогравіметричних досліджень визначено втрату маси покриттів залежно від температури, досліджено енергію активації за температурного розкладу покриттів і встановлено, що для органо-неорганічного покриття вона сягає 21,87 кДж/моль, а у разі введення високотемпературних речовин – збільшується утричі, що дає можливість зробити висновок про доцільність застосування наповнювачів на основі високотемпературних речовин для підвищення ефективності. Однак додавання до покриття металургійного шламу спочатку протидіяло термічному впливу, але згодом призвело до підвищення. Ключові слова: вогнестійкість, покриття, деревина, втрата маси, температура, енергія активації.

Reducing the fire prevention of timber is not only an economic task, but also has a social and environmental focus. From economic, technological and environmental perspective, an important problem in ensuring the viability and safe operation of construction sites is the development of fire-retardant coatings for wooden structures. The construction is increasingly looking for new highly effective means of fire protection of wood and wood products which should not only ensure the standardized fire resistance of wood, but also to maintain its operational parameters to solve environmental safety and durability. Studies of the effect of the radiation panel on the ignition of the wood sample have set the parameters of the flame ignition, which makes it possible to influence this process. It is proved that they consist in the formation of a layer of organic material on the surface, which provides heating to a critical temperature, when the intensive decomposition of the material begins with the release of the required amount of combustible gases and their ignition. This makes it possible to determine the effect of fire protection and the properties of protective compositions on the process of slowing down the rate of burning of wood. Experimental studies have confirmed that the untreated sample of wood, under the thermal action of the radiation panel has taken up, the flames spread over the entire surface, which led to its combustion. The application of a fire retardant varnish under the influence of temperature leads to a layer of foam coke and inhibition of heat transfer of high-temperature flame to the material and its ignition. Thanks to this, it became possible to determine the conditions for changing the parameters of combustion and braking during fire protection of wood, by forming a barrier for thermal conductivity. Thus, there is reason to argue for the possibility of directional control of the processes of fire protection of wood by the use of fireproof coatings that can form a protective layer on the surface of the material, which slows down the rate of burning of wood.

Aim. To determine and estimate the impact of phytopotential of cultivated plants on the fertility indices of podzolic soils, the main factors, limiting the performance of crops, and to establish economic effi ciency of cultivating phytomeliorants, different in their physiological properties. Methods. Field, laboratory, mathematical-statistical. Results. Comprehensive four-year-long studies (2013–2017) established that the optimization of physical and chemical properties of podzolic soils is achieved via the application of phytomeliorant measures. First and foremost, these measures are aimed at preventing the decalcifi cation of soils, i.e. they condition the accumulation of an active Са 2+ ion, which promotes improving the soil characteristics due to progressing development of cumulative soil genesis. It was established that with the mass of alfalfa roots of 9.7 t/ha and sainfoin of 9.9 t/ha, the 0–100 cm layer of podzolic chernozem contains 148.6 and 109.2 kg/ha СаО respectively. Enriching the root-containing layer of soil with calcium compounds promotes replenishing the soil with active calcium, thus ensuring the optimization of the lime potential (pH – 0.5pCa). The latter affects both the acid-alkaline balance and the regulation of physical and chemical processes in soil. It was established that after three years of phytomelioration, the soil in variants with perennial grasses is characterized with higher buffer against acid-alkaline load compared to the control variant which is confi rmed with the indices of acid-alkaline buffer. Taking the abovementioned into consideration, one may assume that the very increase in the activity of calcium is one of buffer mechanisms of soil against acidifi cation. It was proven that phytomelioration is effi cient in terms of improving physical properties of soils, and soil structure, in particular, due to the decrease in the number of dusty and lumpy fractions. It was established that due to phytomeliorant measures the saturation of soil-colloid absorbing complex with calcium ensures intense improvement of water resistance of aggregates for two years. It was proven that optimal values of soil composition density for most crops of the Forest-Steppe zone may be achieved while cultivating Sudan grass for one year. The improvement of the main indices of soil fertility via phytomeliorative measures led to the increase in the performance of corn and barley and improvement of quality properties of grain. Conclusions. Phytomeliorative technology of cultivating podzolic soils ensures the balanced use of soils with simultaneous orientation towards preservation of resources, ecological safety and supplying the population with stable yield of crops with high quality of products.

The present work researches processes of heat transfer by samples of mats manufactured from reed. Due to the unique properties of the reed, such as medium density, low thermal conductivity, relatively high weather resistance, high chemical resistance, possibility to produce parts on-site, cost-effectiveness and others, reed products are widely used in building construction despite the high rate of development of new technologies. The mechanisms of heat insulation in the result of energy transfer through the material are established, which makes it possible to influence this process. It is proven, that the mechanisms are conditioned upon the increased porosity of the material. Thus, decreasing volume weight results in decreasing thermal conductivity, and vice versa. The simulation of the heat transfer process with the flameproof coating is carried out, the dependencies of the thermophysical coefficients on the temperature are determined. Based on the obtained dependencies, the coefficient of thermal conductivity for the products made of dry pine wood is calculated and makes 0.056 W / (m · K). Features of slowing down the process of heat transfer to material made of wood wool and glue binding agent with the formation of pores were studied. This is explained by the fact that there is no movement of air in large pores, accompanied by heat transfer. Thus, there are grounds to argue for the possibility of directed regulation of the processes of the formation of thermal insulation products using the reeds characterized by voids in the stems.

The article presents the results of the protection of wooden building structures with intumescent coatings for the resistance to high-temperature flame resistance. The essence of the method of determining the effectiveness of the coating was the impact of standardized flames on fireproof wood and the definition of values. Based on the data obtained, criteria were established that correspond to the degree of damage to the specimens and the increase in the combustion temperature, resulting in a decrease in weight loss. To determine the effectiveness of fire protection in the developed coatings studies on the combustibility of wood in terms of weight loss and flue gas temperature were conducted, and it was found that with coating the degree of damage to the samples in length does not exceed 26%, the degree of damage by mass does not exceed 2% and the flue gas temperature does not exceed 115°C. However, a protective layer that is of considerable thickness to the building structure should be applied to ensure its protection, since, at a higher intensity of thermal action, the fire resistance of the wood may decrease due to the formation of a low coke layer. Full-scale tests using model specimens of wooden beams under the action of a high-temperature flame furnace have shown that the intumescent coating can withstand high temperatures, effectively preventing the penetration of heat into the material due to the formation of a swollen coke layer, which affects the speed and depth of the temperature.

The theoretical and practical principles of fire protection of wooden building structures are stated. Based on the performed scientific analysis it is shown that the schedule of wood from the action of high temperature determines the reliability and durability of building structures. The features of the process of weight loss during the operation of fireproof wood, a decrease in the rate of burnout depending on the properties of the protective coating are disclosed. The basic operational properties of flame retardants are experimentally determined and their suitability for use in building structures is established, technical solutions and recommendations for the practical implementation of fire protection at construction sites for the application, receipt and operation of materials are given. Designed for specialists and scientists engaged in practical and scientific activities in the field of protection of building structures.