Ukrainian Journal of Forest and Wood Science

The article reflects the results of research on influence of a number of fillers on weight loss of wood protected with a coating based on inorganic and organic substances in the process of thermal impact. A specific feature was the research of fire retardant efficiency of a coating composition. The solution to this problem was searched for by the standardized methods. The influence of the fillers under conditions of a high-temperature heat flux on the dynamics of weight loss of wood treated with fire retardants was revealed, and the mechanism of the kinetics of the influence of the filler was determined. The latter is characterized by lowering rate and weight loss. Inter alia, for a sample of wood with fire retardant coating containing high-temperature filler a gradual temperature decrease occurs, i.e., the functioning of the coating was noted, and hence, the lowering of smoke formation ability was revealed. To determine the fire retardant efficiency when using high-temperature fillers of coating, the combustibility groups of wood were established by loss of weight and increase of smoke fumes temperature. It was revealed that the treated wood has become a hardly combustible material. The loss of weight of coatings versus temperature was determined as a result of the thermogravimetric analysis. Based on the named analysis, the activation energy was studied under conditions of thermal decomposition of the coatings. It was found that the latter was equal to 21.87 kJ/mole for the coating based on organic and inorganic substances, but in case of introduction of high-temperature substances, it increased three times. This fact makes it possible to draw a conclusion on the expedience of application of fillers based on high-temperature substances for raising the efficiency of coatings based on organic and inorganic substances.

fire resistance, coating, wood, weight loss, temperature, activation energy