INVESTIGATION OF THE PRODUCTION AND PHYSICO-CHEMICAL PROPERTIES OF MODERN FLAME RETARDANTS

ABSTRACT

During this study, fire-resistant antipyrene was obtained from boric acid and urea. The infrared spectrum of the resulting antipyrene as well as the main physicochemical indicators were studied. Also, the indicators of effectiveness in increasing the fire-resistant nature of the wood materials of the antipyrene obtained in the test-experiments studied.

АННОТАЦИЯ

В ходе этого исследования из борной кислоты и мочевины был получен огнестойкий антипирен. Были изучены инфракрасный спектр полученного антипирена, а также основные физико-химические показатели. Также изучались показатели эффективности в повышении огнестойкости древесных материалов антипирена, полученные в тест-экспериментах.

Keywords: flame-retardants, infrared spectrum, wood materials, coatings, boric acid and urea.

Ключевые слова: антипирены, инфракрасный спектр, древесные материалы, покрытия, борная кислота и мочевина.

Introduction. In recent years, the volume of production of substances and other additives used to increase the fire resistance of polymers and plastics has been increasing worldwide. In particular, over the past 2021, this type of chemicals and additives produced for 27.18 trillion US dollars, while in 2022 it amounted to 27.42 trillion US dollars [1] (fig. 1).

Figure 1. Production of flame retardants in the world (trillion USD doll)

Today, the production of a new generation of flame retardants based on modern technologies and using highly effective flame retardants is one of the urgent tasks [2-3].

Methods and materials. Fire-fighting properties are demonstrated by impregnating the proposed flame-retardants containing boric acid and urea on the surface of combustible materials or by modifying them with polymer materials to form gel-like coatings. Flame-retardants synthesized based on the interaction of phosphorus containing, nitrogen containing and boron-containing compounds, and the properties of these flame-retardants studied [4]. When flame-retardants obtained, the reaction processes carried out in two parts.

In the first stage, a reaction of boric acid and urea in 1:1 mass ratios carried out. As a result, an intermediate product obtained at a yield of 65-68%.

In this reaction, boric acid condensed with urea, resulting in dimers. The resulting boron stored flame-retardants have high-efficiency properties, and good results can be obtain when applied to wooden materials by soaking them dissolved in water.

Flame retardant obtained as result of their composition from condensed urea and phosphate acid compounds characterized by the absence of high toxicity specificity, low cost and positive quality of use.

Results and discussion. In this experiment, the physicochemical indicators of the obtained antipenes studied. The results indicate that the difference in the indicators of the substance obtained when the mass ratios of the starting substances entering the reaction are changed is not observe (table 1).

Table 1.

The main physico-chemical indicators of antipren from boric acid and urea

Also, in the course of practical experiments, an analysis of the infrared spectrum of flame retardants was carried out, which is used to increase the effective fire-resistant properties of wood materials made of boric acid and urea (fig. 1).

Figure 2. Infrared spectrum indicators of the antipren obtained in boric acid and urea

At the same time, a 20% water solution of refractory antipren obtained during practical experiments was prepared and soaked in wooden material for 1-1.5 hours in a special bath, at a temperature of 40-50^oS. As a result, the fire resistance of wood materials treated with flame-retardant antipyrine was studied the basis
of GOST 16363-98 [5].

During the test-experiment, wood samples placed vertically in a black steel tube with a length of 166 mm and a diameter of 50 mm. The flame of the alcohol burner given under the sample, which was released 5 mm from the pipe. The distance from the upper edge of the burn to the sample was placed at 10 mm. The sample flame held
1 minit 30 c, and the sample's independent combustion and duration of combustion were studied after the sample was taken from the flame.

In the process of the research method, the mass loss of wood treated with coatings under favorable conditions for heat accumulation and during fire time analyzed. During the studies, fire-resistant antipyrene treated and untreated wood materials were tested and tested, and the following results obtained (tables 2 and 3).

Table 2.

Indicators of wood materials that aren’t treated with antipyrenes

Wood samples that not treated with antipyrenes had a mass loss of 67.3% when studied for fire resistance and were found to belong to the flammable group.

Table 3.

Indicators of wood materials that treated with antipyrine

According to the results of the test experiment, the weight loss of a sample of wood treated with flame-retardants was 1.31%, and this indicator indicates that refractory materials belong to the composition of the first group.

Thus, during practical test-experiments, an antipyrene agent obtained from boric acid and urea. A solution was prepared from this antipyrene and applied in order to increase the fire-resistant nature of wood materials. The results of the test scientifically proven that the fire-resistant property of antipyrene is positive.

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